CN105374323B

CN105374323B - Dot matrix backlight drive method, device and system

Info

Publication number: CN105374323B
Application number: CN201510960759.9A
Authority: CN
Inventors: 娈靛钩; 段平
Original assignee: Shenzhen TCL New Technology Co Ltd
Current assignee: Shenzhen TCL New Technology Co Ltd
Priority date: 2015-12-18
Filing date: 2015-12-18
Publication date: 2018-02-13
Anticipated expiration: 2035-12-18
Also published as: WO2017101273A1; CN105374323A

Abstract

The invention discloses a kind of dot matrix backlight drive method, this method includes：According to the TV signal of input, each pulse width modulation (PWM) data of LED lamp are calculated in control dot matrix backlight；According to the PWM count evidence, statistic histogram is made, and the current parameters for controlling each LED are calculated according to the statistic histogram；According to each LED described in the PWM count evidence and the current parameters independent control, the dot matrix backlight is driven.The invention also discloses a kind of dot matrix backlight driving device.The present invention, which realizes, all to distribute according to need the electric current of all LEDs in dot matrix backlight, while power consumption is reduced, television image is integrally reached optimal display result, avoids power attenuation and energy waste.

Description

Dot matrix backlight drive method, device and system

Technical field

The present invention relates to dot matrix backlight driver technical field, more particularly to a kind of dot matrix backlight drive method, device And system.

Background technology

With the demand of user and the development of backlight technology, liquid crystal display takes traditional the moon of rapid generation in various fields Extreme ray pipe Display Technique so that LCD (Liquid Crystal Display, liquid crystal display) display screen becomes household electrical appliances market Leading products.

Current LCD flat panel TV much all uses LED (Light Emitting Diode, light emitting diode) array light Source.LED dot matrix backlights have the advantages that good color rendition, power saving, long lifespan, gradually instead of traditional unilateral or bilateral lamp The side entering type light source of bar formula deployment.To various sizes of television set, deployment and side by the array light source LED of fair amount Case designs, and making the complete machine picture of the television set, not only brightness is high but also picture light sensation is uniform, solves traditional side entering type light source Need the defects of multiple guide-lighting, luminance shortage and light sensation are uneven.

For the brightness control of LED array light sources, mainly there are two kinds of approach at present：One is the driving electricity for adjusting LED Flow size；Another be adjust LED drive circuit switch time, namely control LED power supply circuit ON time and Turn-off time, normally referred to as PWM (Pulse-Width Modulation, pulse width modulation), LED power supply circuit is led The logical time accounts for ON time and the ratio of turn-off time sum is referred to as dutycycle., can by the driving current and dutycycle of LED To control the luminosity of each LED and consumption power, so as to adjust and control the complete machine picture brightness size of television set, and The watt level of television set complete machine consumption.

It is most of for backlight consumption due to the power of LCD flat panel TV consumption, the consumption of miscellaneous part compared with It is few, therefore, mainly by controlling the power of backlight to reach the environmental requirement of energy-saving and emission-reduction.The power of existing regulation backlight Method, mainly by adjusting the dutycycle of each LED, and in unified regulation backlight all LEDs current value size Realize, or by region division, the current value size of unified regulation LED is realized in units of region.

For example, using the optimal brightness and image quality effect that can reach backlight during rated current, now power is larger, right The demanded power output of power supply is higher, wastes the energy.

, can be by the electricity of all LED in backlight when the power of backlight is reduced into half to reduce the power of backlight Stream is adjusted to the half of rated current to realize.Now, because image quality effect is not beautiful enough, even if by adjusting accounting for for LED Empty ratio, the part picture dutycycle for making to become clear in picture reaches 100%, but is limited to identical current value, and contrast is small, becomes clear Part is not strong with the picture otherness of shadow portion, causes picture effect poor, and the LED of shadow portion current waist.

Or 16 method driving LED array light sources are dragged using one in current portions backlight, namely by a driving IC (integrated circuit, integrated circuit), while control 16 LEDs.Due to the ten of same driving IC controls The current value of six LEDs is identical, can only realize the Partial controll of backlight, and image quality effect can not still reach the ideal of user Viewing effect.

Thus, it is possible to find out, although prior art can carry out PWM regulation and control to each LED in dot matrix backlight, Due to being uniformly controlled for electric current, if ensureing picture brightness, power consumption can be caused high, the energy largely wastes；And reduce work( During rate, television picture quality is poor, influences the viewing experience of user.

The content of the invention

It is a primary object of the present invention to provide a kind of dot matrix backlight drive method, device and system, it is intended to solve to work as Preceding dot matrix backlight causes that power consumption is high, technical problem of energy waste to ensure image quality.

To achieve the above object, the present invention provides a kind of dot matrix backlight drive method, the dot matrix backlight driver side Method comprises the following steps：

According to the TV signal of input, the pulse of each LED lamp in control dot matrix backlight is calculated Width modulated PWM count evidence；

According to the PWM count evidence, statistic histogram is made, and it is described each according to the statistic histogram control to be calculated The current parameters of LED；

According to each LED described in the PWM count evidence and the current parameters independent control, the dot matrix backlight is driven.

Preferably, the PWM count is according to each PWM count evidence for each LED in the corresponding dot matrix backlight, the basis The PWM count evidence, statistic histogram is made, and the electric current for controlling each LED is calculated according to the statistic histogram The step of parameter, includes：

According to the PWM count evidence and the dot matrix backlight general power, the rated voltage that are pre-configured with, calculate in dot matrix backlight The average current of each LED；

Each PWM count evidence of each LED in the corresponding dot matrix backlight, makes statistic histogram；

According to the average current, electric current straight line is made in the statistic histogram, each PWM in the statistic histogram Data correspond to the current parameters on the electric current straight line；

Single step counterclockwise rotates the electric current straight line, and according to postrotational electric current straight line, it is described each that control is calculated The current parameters of LED.

Preferably, the single step counterclockwise rotates the electric current straight line, and according to postrotational electric current straight line, is calculated The step of current parameters for controlling each LED, includes：

According to default rule, the center equalization point of the statistic histogram is chosen on the electric current straight line；

Using the center equalization point as rotary middle point, single step counterclockwise rotates the electric current straight line, and rotary step is pre- If threshold value；

According to default rated current, the maximum current parameter of each LED is calculated, and controls each PWM Current parameters corresponding to data are no more than the maximum current parameter and are not less than default minimum current parameter；

According to postrotational electric current straight line, the current parameters for controlling each LED are calculated.

Preferably, it is described according to postrotational electric current straight line, each electricity of LED is calculated in control dot matrix backlight The step of flowing parameter includes：

According to postrotational electric current straight line, each PWM count current parameters corresponding to are calculated；

According to the rated voltage, each PWM count evidence and corresponding current parameters, it is calculated according to each PWM Data and corresponding current parameters control the driving power of each LED；

Judge whether the driving power reaches the general power；

If the driving power is not reaching to the general power, returns and perform step：Using the center equalization point as rotation Turn central point, single step counterclockwise rotates the electric current straight line, and rotary step is default threshold value；

If the driving power reaches the general power, by each PWM count corresponding to current parameters, as control The current parameters of each LED simultaneously store the current parameters.

In addition, to achieve the above object, the present invention also provides a kind of dot matrix backlight driving device, the dot matrix backlight Drive device includes：

Image processing module, for the TV signal according to input, it is calculated in control dot matrix backlight and each lights The pulse width modulation (PWM) data of diode (LED) lamp；

Driven management module, for according to the PWM count evidence, making statistic histogram, and according to the statistic histogram The current parameters for controlling each LED are calculated；

Drive circuit module, for each LED according to the PWM count evidence and the current parameters independent control, drive Move the dot matrix backlight.

Preferably, the PWM count is according to each PWM count evidence for each LED in the corresponding dot matrix backlight, the driving Management module includes：

Electric current averaging unit, for according to the PWM count evidence and the dot matrix backlight general power being pre-configured with, specified electricity Pressure, calculate the average current of each LED in dot matrix backlight；

Histogram production unit, for each PWM count evidence of each LED in the corresponding dot matrix backlight, make Statistic histogram；

Electric current straight line units, for according to the average current, making electric current straight line, described in the statistic histogram Each PWM count is according to the current parameters on the corresponding electric current straight line in statistic histogram；

Single step rotary unit, the electric current straight line is rotated for single step counterclockwise, and according to postrotational electric current straight line, meter Calculate the current parameters for obtaining controlling each LED.

Preferably, the single step rotary unit includes：

Central point subelement, for according to default rule, the statistic histogram to be chosen on the electric current straight line Center equalization point；

Subelement is rotated, for using the center equalization point as rotary middle point, it is straight that single step counterclockwise rotates the electric current Line, rotary step are default threshold value；

Border subelement, for the maximum current parameter of each LED according to default rated current, to be calculated, And each PWM count current parameters corresponding to are controlled to be no more than the maximum current parameter and be not less than default minimum current Parameter；

Computation subunit, for according to postrotational electric current straight line, being calculated and controlling the electric current of each LED to join Number.

Preferably, the computation subunit includes：

First computation subunit, for according to postrotational electric current straight line, each PWM count electricity corresponding to be calculated Flow parameter；

Second power subelement, for according to the rated voltage, each PWM count evidence and corresponding current parameters, meter Calculate and obtain the driving power that each LED is controlled according to each PWM count evidence and corresponding current parameters；

3rd judgment sub-unit, for judging whether the driving power reaches the general power；

4th obtains subelement, if reaching the general power for the driving power, by each PWM count according to corresponding Current parameters, as the current parameters for controlling each LED and store the current parameters；

The rotation subelement, if being additionally operable to the driving power is not reaching to the general power, put down with the center Weighing apparatus point is rotary middle point, and single step counterclockwise rotates the electric current straight line.

In addition, to achieve the above object, the present invention also provides a kind of dot matrix backlight drive system, the dot matrix backlight Drive system includes television video image procossing MEMC modules, LED lamp drive control management module and LED and driven Dynamic circuit module, wherein：

The television video image procossing MEMC modules, for the TV signal according to input, are calculated control dot matrix The pulse width modulation (PWM) data of each LED lamp in backlight；PWM count evidence is sent to the LED Drive control management module；

The LED drive control management module, for receiving the television video image procossing MEMC modules transmission The PWM count evidence；According to the PWM count evidence, statistic histogram is made, and control institute is calculated according to the statistic histogram State the current parameters of each LED；The PWM count evidence and the current parameters are sent to the LED lamp drive circuit module.

The LED lamp drive circuit module, the PWM sent for receiving the LED drive control management module Data and the electric current；According to each LED described in the PWM count evidence and the current parameters independent control, the dot matrix is driven Backlight.

Preferably, the LED drive control management module include serial peripheral equipment interface SPI bus data receiving unit, SPI receive data buffer, central cpu processing unit, PWM count according to conversion calculation processing unit, SPI send data buffer and Spi bus data transmission unit, wherein：

The spi bus data receipt unit, the PWM sent for receiving the television video image procossing MEMC modules Data；

The SPI receives data buffer, for storing the PWM count evidence；

The central cpu processing unit, for controlling, coordinating the processing of the PWM count evidence；

The PWM count is according to conversion calculation processing unit, for according to the PWM count evidence, making statistic histogram, and according to The current parameters for controlling each LED are calculated in the statistic histogram；

The SPI sends data buffer, for storing the current parameters；

The spi bus data transmission unit, for the PWM count evidence and the current parameters to be sent into the LED Lamp drive circuit module.

A kind of dot matrix backlight drive method of proposition of the embodiment of the present invention, device and system, believe according to the TV of input Number, each pulse width modulation (PWM) data of LED lamp are calculated in control dot matrix backlight；Then, according to PWM count evidence, statistic histogram is made, and the current parameters for controlling each LED are calculated according to statistic histogram；Then, root According to PWM count evidence and each LED of current parameters independent control, dot matrix backlight is driven.The present invention is realized in dot matrix backlight The electric current of all LEDs is all distributed according to need, and while power consumption is reduced, television image is integrally reached optimal display result, is kept away Power attenuation and energy waste are exempted from.

Brief description of the drawings

Fig. 1 is the schematic flow sheet of dot matrix backlight drive method first embodiment of the present invention；

Fig. 2 is a kind of dot matrix backlight LED driver IC circuits schematic diagram of the embodiment of the present invention；

Fig. 3 is the schematic flow sheet of dot matrix backlight drive method second embodiment of the present invention；

Fig. 4 is the schematic flow sheet of dot matrix backlight drive method 3rd embodiment of the present invention；

Fig. 5 is the schematic flow sheet of dot matrix backlight drive method fourth embodiment of the present invention；

Fig. 6 is a kind of statistic histogram and electric current straight line schematic diagram of the embodiment of the present invention；

Fig. 7 is the high-level schematic functional block diagram of dot matrix backlight driving device first embodiment of the present invention；

Fig. 8 is the high-level schematic functional block diagram of dot matrix backlight driving device second embodiment of the present invention；

Fig. 9 is the high-level schematic functional block diagram of dot matrix backlight driving device 3rd embodiment of the present invention；

Figure 10 is the high-level schematic functional block diagram of dot matrix backlight driving device fourth embodiment of the present invention；

Figure 11 is the module diagram of dot matrix backlight drive system first embodiment of the present invention；

Figure 12 is the module diagram of dot matrix backlight drive system second embodiment of the present invention.

The realization, functional characteristics and advantage of the object of the invention will be described further referring to the drawings in conjunction with the embodiments.

Embodiment

It should be appreciated that the specific embodiments described herein are merely illustrative of the present invention, it is not intended to limit the present invention.

The primary solutions of the embodiment of the present invention are：According to the TV signal of input, control dot matrix backlight is calculated The pulse width modulation (PWM) data of each LED lamp in source；According to the PWM count evidence, statistic histogram is made, And the current parameters for controlling each LED are calculated according to the statistic histogram；According to the PWM count evidence and the electricity Each LED described in flowing parameter independent control, drives the dot matrix backlight.

Due to prior art being uniformly controlled due to electric current, if ensureing picture brightness, power consumption can be caused high, energy Source largely wastes；And when reducing power, television picture quality is poor, influences the viewing experience of user.

The present invention provides a solution, individually carries out PWM controls and electric current control to each LED in a back of the body backlight System, coordinates the actual content distribution according to need electric current of television image, and maximal efficiency make use of LED light source and power.Realize While reducing point back of the body backlight consumption power, ensure television image effect.

Reference picture 1, dot matrix backlight drive method first embodiment of the present invention provide a kind of dot matrix backlight drive method, The dot matrix backlight drive method includes：

Step S10, according to the TV signal of input, each LED in control dot matrix backlight is calculated The pulse width modulation (PWM) data of lamp.

The embodiment of the present invention is mainly used in the driving of dot matrix backlight, is reducing to the same of power configuration power demand When, ensure the picture image quality shown.

The present embodiment can apply to the LED of LCD (Liquid Crystal Display, liquid crystal display) flat panel TV (Light Emitting Diode, light emitting diode) array light source dot matrix backlight driver, can be used for other displays Dot matrix backlight driver, can be according to being actually needed flexible setting., can by dot matrix backlight drive method proposed by the present invention To ensure that the picture brightness of television set meets the needs of high image quality, while will not be because of being greatly reduced for power and by bright Development rings.The demand for both meeting energy-conserving and environment-protective emission reduction is realized, while in turn ensure that the picture brightness of television set reaches optimal Quality, that is, the embodiment of the present invention can greatly improve image quality under the configuration of identical output power of power supply.

The present embodiment is illustrated with the LED dot matrix backlight electric power driving of television set.

Specifically, as a kind of embodiment, after television set starts, TV video processor front end, namely centre Reason device CPU television video image procossing MEMC (estimate by Motion Estimate and Motion Compensation, motion Meter and motion compensation) module dynamic access TV signal source input every frame television image TV signal.

Then, television video image procossing MEMC modules draw the TV in frame buffer according to the quantity of LED array light sources Face is divided into picture block equal with the LED quantity in LED array light sources, one-to-one.

Then, the luminance signal in the TV signal of input, the brightness value of each picture block is obtained.Statistics is every The brightness of one picture block, and brightness histogram is made, calculate each described picture block further according to this brightness histogram Mean flow rate, and the brightness value using obtained mean flow rate as LED corresponding to each picture block.Then, according to each LED PWM (Pulse-Width Modulation, the pulse width modulation) data for controlling each LED are calculated in the brightness value of lamp.

Then, obtained PWM count evidence is output to the driving of LED array light sources by television video image procossing MEMC modules Plate, for controlling the luminosity of corresponding LED.

When the PWM count of all LEDs finishes according to calculating, log-on data sending module, as host computer, will first send out immediately The data encoding packing sent, then will by SPI (Serial Peripheral Interface, Serial Peripheral Interface (SPI)) bus Data are sent to the driving plate of LED array light sources.

Thus, the driving plate of LED array light sources obtains controlling the PWM count evidence of each LED.

The numerical value of PWM count evidence is bigger, also means that this PWM count picture corresponding to is brighter；The numerical value of PWM count evidence is got over It is small, also mean that this PWM count picture corresponding to is darker.

In the present embodiment, obtained PWM count evidence is dutycycle.The conducting of LED power supply circuit is defined in the present embodiment Time, account for ON time and the ratio of turn-off time sum, referred to as dutycycle, such as 80%, 60% etc..Can be according to each The dutycycle of LED, the power supply circuit ON time of each LED of independent control, carry out local backlight regulation.

Step S20, according to the PWM count evidence, statistic histogram is made, and control is calculated according to the statistic histogram Make the current parameters of each LED.

The driving plate of LED array light sources is managed by LED drive control management module.Wherein, LED driving control Management module processed include SPI receive data buffer, spi bus data receipt unit, PWM count according to conversion calculation processing unit, Central cpu processing unit, SPI send data buffer and spi bus data transmission unit.

Central cpu processing unit control spi bus data receipt unit in LED array light source driving plates receives upper After the data that machine is sent, parse to obtain the PWM count evidence of each LED by cis-position sequence by data.Then, will obtain PWM count receives data buffer according to deposit SPI.

Each LED in obtaining dot matrix backlight electric power PWM count after, LED drive control management module is according to obtaining PWM count evidence, make statistic histogram, and calculate the current parameters of each LED in control dot matrix backlight.

Specifically, the central cpu processing unit of LED drive control management module turns PWM count according to PWM count evidence is inputed to Calculation processing unit is changed, PWM count calculates each LED according to conversion calculation processing unit according to obtained PWM count evidence, conversion Driving current parameter.

As a kind of embodiment, first, PWM count is according to conversion calculation processing unit according to the dot matrix backlight being pre-configured with General power, and rated supply voltage, PWM count evidence, the average current value of LED in dot matrix backlight is calculated, by average electricity Initial current value of the flow valuve as each LED.

Then, PWM count makes statistic histogram according to conversion calculation processing unit according to obtained PWM count evidence.

Maximum and minimum value of the PWM count in are obtained, the interval value of PWM count evidence is calculated；Then, according to default Group is worth to the group number of PWM count evidence away from the section with PWM count evidence, completes the packet to PWM count evidence；Or according to default group of number The group of PWM count evidence is worth to away from completing to PWM count according to packet with the section of PWM count evidence；Then, with the numerical value of PWM count evidence, I.e. dutycycle is counted as abscissa with the quantity of the occurrence number of PWM count evidence, namely LED as ordinate, making Histogram.

Statistic histogram includes block diagram of each PWM count according to group, and each block diagram includes current PWM count according in group, PWM The occurrence number of data and corresponding PWM count value.

Statistic histogram includes block diagram of each PWM count according to group, and each current PWM count of histogram graph representation is according in group, PWM The number range and occurrence number of data.

Then, in statistic histogram, electric current straight line is made according to average current value.Each PWM count is according to corresponding current straight line In current parameters.

Then, according to default rule, the center equalization point of selection statistic histogram in electric current straight line.

Then, using this center equalization point as center, single step rotatory current straight line counterclockwise, the larger LED of PWM count value is made Lamp obtains bigger current value, and the less LED of PWM count value obtains smaller current value, with strengthen in picture light with The contrast of shadow portion.

In electric current straight line rotary course, PWM count is according to conversion calculation processing unit according to the postrotational electric current of each single step Straight line, each PWM count current parameters corresponding to are calculated, so as to obtain the current parameters of each LED.Then, according to acquisition Each LED current parameters, calculate the power consumed during all LEDs in control dot matrix backlight.

When the power of consumption meets the dot matrix backlight general power being pre-configured with, stop the rotation electric current straight line, and with this When electric current line correspondences each current parameters, the current parameters as each LED in control dot matrix backlight.

It should be noted that during rotatory current straight line, the step-length often rotated once is default threshold value, can be according to actual need Flexibly to set.For example, if desired accelerating the rotary speed of electric current straight line, the consumption power for making to be calculated is rapidly achieved in advance The dot matrix backlight general power of configuration, then the threshold value of rotary step can be set larger；If control electric current straight line is not required Rotary speed, in order to carry out control accurate, the threshold value of rotary step can be set smaller.

Thus, PWM count obtains controlling the current parameters of each LED in dot matrix backlight according to conversion calculation processing unit. In the present embodiment, the current parameters obtained are current value.

Then, the current parameters deposit SPI of each LED is sent data buffer storage by PWM count according to conversion calculation processing unit Device.The PWM count evidence and current parameters of storage are sent to each LED by central cpu processing unit control spi bus data transmission unit The drive circuit module of lamp.

The present embodiment is by obtaining the PWM count evidence per frame display picture, by all PWM counts according to feeding PWM count according to conversion Calculation processing unit, PWM count according to conversion calculation processing unit according to dot matrix backlight drive method provided by the invention, according to PWM count is according to effective control electric current data that corresponding each LED is calculated.Then, central cpu processing unit is by PWM count evidence The LED current data of modular converter output is flushed to the current control circuit of corresponding each LED, used by spi bus To control the current value size of each LED.Central cpu processing unit is corresponding every according to being flushed to by spi bus by PWM count The PWM on-off circuits of individual LED, this PWM count is accurately write into each LED according to according to the address mapping relation table of LED PWM registers are driven, to adjust the contactor time of each LED, so allow the PWM pulse duty cycles of each LED Can freely it be set with conducting electric current.

Step S30, each LED according to the PWM count evidence and the current parameters independent control, drives the dot matrix Backlight.

The drive circuit module of LED receives the PWM count evidence and current parameters of each LED in dot matrix backlight, independent Each LED is controlled, drives dot matrix backlight.

Specifically, as a kind of embodiment, each LED in dot matrix backlight is each equipped with independent PWM switches Circuit and current control circuit, reference picture 2 can be by driving the inside of IC (integrated circuit, integrated circuit) Design, which improves, to be realized, or is realized in driving IC external circuit design.

The drive circuit module of LED switchs electricity according to the PWM count evidence of each LED of acquisition by the PWM of each LED Road, PWM controls are carried out to each LED respectively, control the pulse duty cycle of each LED.

Meanwhile the drive circuit module of LED passes through the electric current of each LED according to the current parameters of each LED of acquisition Control circuit, current control is carried out to each LED respectively.

Thus, the drive circuit module of LED realizes the driving to dot matrix backlight, shows current television image.

In the present embodiment, by obtaining each frame picture of TV in real time, and carry out in real time dynamic data analysis and Calculate, so as to ensure the continuity of television image and high image quality.

In the present embodiment, first, according to the TV signal of input, it is calculated in control dot matrix backlight and each lights The pulse width modulation (PWM) data of diode (LED) lamp；Then, according to PWM count evidence, statistic histogram is made, and it is straight according to statistics The current parameters for controlling each LED are calculated in square figure；Then according to the PWM count evidence and current parameters of each LED, independent control Each LED, drive dot matrix backlight.The present embodiment by the PWM count according to acquisition according to make statistic histogram, so as to adjust The current parameters of each PWM count LED corresponding to, realize and the electric current of all LEDs in dot matrix backlight are all distributed according to need, Under conditions of power consumption is ensured, television image is integrally reached optimal display result, avoid power attenuation and energy waste.

Further, reference picture 3, dot matrix backlight drive method second embodiment of the present invention provide a kind of dot matrix backlight Driving method, based on the embodiment shown in above-mentioned Fig. 1, the PWM count evidence is each LED in the corresponding dot matrix backlight Each PWM count evidence, the step S20 include：

Step S21, according to the PWM count evidence and the dot matrix backlight general power, the rated voltage that are pre-configured with, dot matrix is calculated The average current of each LED in backlight.

After the PWM count evidence of each LED in obtaining dot matrix backlight electric power, the central cpu of LED drive control management module Processing unit by PWM count according to input to PWM count according to conversion calculation processing unit, PWM count according to conversion calculation processing unit according to must The PWM count evidence arrived, conversion calculate the driving current parameter of each LED.

As a kind of embodiment, PWM count is according to conversion calculation processing unit according to the dot matrix backlight total work being pre-configured with Rate, and rated supply voltage, PWM count evidence, the average current value of LED in dot matrix backlight is calculated, by average current value Initial current value as each LED.

Specific calculating process is as follows：

First, according to PWM count according to the average value for calculating PWM count evidence.

Take and n LED is shared in current dot matrix backlight, the PWM count value of each LED is PWM1, PWM2, PWM3 ... PWMn, the average value of PWM count evidence is PWM_avg, then according to formula PWM_avg=(PWM1+PWM2+PWM3+ ...+PWMn)/n are calculated To PWM_avg。

Then, according to the dot matrix backlight general power being pre-configured with, and rated supply voltage, the average value of PWM count evidence, meter Calculate the maximum allowable average current value of current dot matrix backlight.

It is P to take general power, and rated supply voltage V, the average value of PWM count evidence is PWM_avg, average current value I_avg, then According to formula I_avg=P/ (V × PWM_avg) I is calculated_avg。

Thus, the average current value of LED in dot matrix backlight is obtained.

Step S22, each PWM count evidence of each LED in the corresponding dot matrix backlight, makes statistic histogram.

PWM count, according to obtained PWM count evidence, makes statistic histogram according to conversion calculation processing unit.

First, maximum PWMmax and minimum value PWMmin of the PWM count in are obtained, the section of PWM count evidence is calculated Value.Interval value can be obtained according to formula PWMmax-PWMmin.

Then, the group number of PWM count evidence is worth to away from the section with PWM count evidence according to default group, is completed to PWM count evidence Packet；Or the group of PWM count evidence is worth to away from completing to divide PWM count evidence according to the section of default group of number and PWM count evidence Group.

Then, with the numerical value of PWM count evidence, namely dutycycle is as abscissa, with the occurrence number of PWM count evidence, namely LED The quantity of lamp obtains statistic histogram as ordinate, making.

Step S23, according to the average current, electric current straight line, the statistics Nogata are made in the statistic histogram Each PWM count is according to the current parameters on the corresponding electric current straight line in figure.

After statistic histogram is obtained, in statistic histogram, electric current straight line is made according to average current value.Each PWM count According to the current parameters in corresponding current straight line.

Specifically, as a kind of embodiment, in statistic histogram, according to the abscissa for representing PWM count value, with PWM Current value corresponding to numerical value is virtual ordinate, obtains virtual coordinates axle.

Then, using average current value as ordinate value, maximum PWMmax and minimum value PWMmin difference of the PWM count in For abscissa, point A and point B, tie point A and point B are obtained, obtains electric current straight line AB.

Now, average current value is each PWM count according to corresponding initial current value, namely the initial current value of each LED.

As another embodiment, electric current straight line also can be arranged to curve, such as 2.2Gamma according to being actually needed (gamma) curve, realize more preferable Picture Showing effect.

The signified electric current straight line of the present embodiment, can be according to being actually needed flexible setting.

Step S24, single step counterclockwise rotates the electric current straight line, and according to postrotational electric current straight line, control is calculated Make the current parameters of each LED.

After electric current straight line is obtained, rotatory current straight line, and according to postrotational electric current straight line, control dot matrix is calculated The current parameters of each LED in backlight.

Specifically, as a kind of embodiment, first, by default rule, statistic histogram is obtained on electric current straight line Center equalization point.

Then, using this center equalization point as center, single step rotatory current straight line counterclockwise, the larger LED of PWM count value is made Lamp obtains bigger current value, and the less LED of PWM count value obtains smaller current value, with strengthen in picture light with The contrast of shadow portion.It should be noted that the rotary step that electric current straight line is rotated each time is default threshold value.

In electric current straight line rotary course, PWM count is according to conversion calculation processing unit according to the postrotational electric current of each single step Straight line, each PWM count current parameters corresponding to are calculated, so as to obtain the current parameters of each LED.

Then, according to the current parameters of each LED of acquisition, disappear when calculating LEDs all in driving dot matrix backlight The power of consumption.

When the power of consumption meets the dot matrix backlight general power being pre-configured with, stop the rotation electric current straight line, and with this When electric current line correspondences each current parameters, it is every as the current parameters of corresponding PWM count evidence, namely in control dot matrix backlight The current parameters of individual LED.

Thus, PWM count obtains controlling the current parameters of each LED in dot matrix backlight according to conversion calculation processing unit. In the present embodiment, the current parameters obtained are current value, and dot matrix backlight driving device writes the current value of each LED Enter into corresponding current control register.

In the present embodiment, preferred, PWM count is according to conversion calculation processing unit according to PWM count evidence and the dot matrix being pre-configured with Backlight general power, rated voltage, calculate the average current of each LED in dot matrix backlight；Then, according to corresponding each LED Each PWM count evidence of lamp, make statistic histogram；Then, according to average current, electric current straight line is made in statistic histogram, respectively PWM count is according to the current parameters on corresponding current straight line；Then, single step rotatory current straight line counterclockwise, and according to postrotational electricity Straight line is flowed, the current parameters of each LED in control dot matrix backlight are calculated.The present embodiment passes through each in dot matrix backlight The average current of LED, determine each LED initial current；Then, by electric current straight line by current parameters corresponding to each LED Function, it is easy to regulate and control；During rotate counterclockwise electric current straight line, the larger LED of PWM count value is set to obtain bigger current value, more It is bright, the less LED of PWM count value obtains smaller current value, and brightness is lower；By corresponding to the adjustment of rotatory current straight line The current parameters of each LED, so that the power of each LED consumption meets the general power pre-set.Thus, the present embodiment is full While foot default general power, the quality of television image is ensure that, realizes the target of energy-saving and emission-reduction, it is green and simultaneously Ensure picture effect, improve Consumer's Experience.

Further, reference picture 4, dot matrix backlight drive method 3rd embodiment of the present invention provide a kind of dot matrix backlight Driving method, based on the embodiment shown in above-mentioned Fig. 3, the step S24 includes：

Step S241, according to default rule, the center that the statistic histogram is chosen on the electric current straight line balances Point.

First, by default rule, the center equalization point of acquisition statistic histogram on electric current straight line.

Specifically, as a kind of embodiment, in counting statistics histogram, each PWM count according to PWM count evidence in group quantity, The PWM count of whole LEDs is accounted for according to the percentage of total amount.Wherein, each PWM count is data according to the occurrence number of PWM count evidence in group The quantity of PWM count evidence in group.

After accounting highest PWM count is obtained according to group, a PWM count evidence in this data group is chosen according to preset rules.PWM The selection rule of data can be the median of PWM count evidence in its affiliated data group, or the maximum of PWM count evidence or Other numerical value of its affiliated data group.

Then, the current value of the PWM count evidence of selection is arranged to average current, obtains corresponding point C on electric current straight line.Point C abscissa is the PWM count value chosen, and ordinate is average current.

Point C is the center equalization point obtained.Hereafter, point C coordinate value is kept constant.

As another embodiment, it can choose on electric current straight line, 2 Along ents of line segment between point A and point B, as Center equalization point.

Any point on line segment AB can also be chosen, as center equalization point according to PWM count according to situation.

PWM count value is abscissa corresponding to obtained center equalization point, and average current is ordinate.Hereafter, center balances The coordinate value of point keeps constant.

Step S242, using the center equalization point as rotary middle point, single step counterclockwise rotates the electric current straight line, rotation Step-length is default threshold value.

After center equalization point is obtained, using this center equalization point as pivot, single step rotatory current straight line counterclockwise. It should be noted that the rotary step that electric current straight line rotates each time is default threshold value, rotary step can be according to processing speed Demand flexibly set.For example, if desired lifting processing speed, the threshold value of rotary step can be set larger；If need Processing accuracy is improved, the threshold value of rotary step can be set smaller.

Because the original state of electric current straight line is parallel with axis of abscissas, therefore rotate counterclockwise such that larger PWM count The corresponding bigger current value of value, the corresponding smaller current value of less PWM count value.

Thereby, it is possible to make the larger LED of PWM count value obtain bigger current value, the less LED of PWM count value obtains Smaller current value, to strengthen the contrast of light and shadow portion in picture.

Step S243, according to default rated current, the maximum current parameter of each LED is calculated, and controls Each PWM count current parameters corresponding to are no more than the maximum current parameter and are not less than default minimum current parameter.

When electric current straight line is rotated, to ensure that electric current drives each LED according to corresponding to obtained each PWM count value When, LED is excessively bright or excessively gloomy, therefore is provided with maximum current parameter and minimum current parameter, ensures electric current straight line During rotation, obtained current parameters make the brightness of LED in the reasonable scope.

Specifically, as a kind of embodiment, first, according to default rated current, the maximum of each LED is calculated Current parameters.

Take rated current specified for I, the maximum of PWM count evidence is PWMmax, and the maximum current of LED is Imax, then root According to formula：

Imax=I is specified × PWMmax, it can be calculated the maximum current value of each LED, namely maximum current parameter.

Therefore, PWM count evidence corresponding with each LED, corresponding current parameters maximum is Imax on electric current straight line.

To ensure that the brightness of each LED is not excessively gloomy, the minimum current parameter Imin of each LED is preset with, thus may be used PWM count evidence corresponding to each LED is obtained, corresponding current parameters minimum value is Imin on electric current straight line.

Thus, each PWM count maximum current parameter and minimum current parameter corresponding to are obtained.

When electric current straight line rotates, current parameters corresponding to maximum PWM count value are controlled to be less than or equal to maximum current parameter, Each PWM count current parameters corresponding to can be achieved and be no more than maximum current parameter；Electric current corresponding to minimum PWM count value is controlled to join Number is more than or equal to minimum current parameter, you can realizes that each PWM count current parameters corresponding to are not less than minimum current parameter.

Step S244, according to postrotational electric current straight line, the current parameters for controlling each LED are calculated.

After electric current straight line carries out single step rotation every time, PWM count rotates according to conversion calculation processing unit according to each single step Electric current straight line afterwards, each PWM count current parameters corresponding to are calculated, so as to obtain the current parameters of each LED.

Thus, PWM count obtains controlling the current parameters of each LED in dot matrix backlight according to conversion calculation processing unit. Then, the current value of each LED is written in corresponding current control register by dot matrix backlight driving device.

In the present embodiment, PWM count chooses system according to conversion calculation processing unit according to default rule on electric current straight line Count the center equalization point of histogram；Then, using center equalization point as rotary middle point, single step rotatory current straight line counterclockwise；Root According to default rated current, the maximum current parameter of each LED is calculated, and controls current parameters corresponding to PWM count evidence not More than maximum current parameter and it is not less than default minimum current parameter；According to postrotational electric current straight line, control is calculated The current parameters of each LED in dot matrix backlight.The present embodiment is rotated to be by Selection Center equalization point with center equalization point Rotating shaft, single step rotatory current straight line counterclockwise, the part for making picture become clear is brighter, and gloomy part is gloomy, strengthens contrast, Ensure the brightness of LED in rational scope simultaneously.Each LED is driven according to obtained current parameters, had both been met in advance The general power of configuration, improves image quality again.

Further, reference picture 5, dot matrix backlight drive method fourth embodiment of the present invention provide a kind of dot matrix backlight Driving method, based on the embodiment shown in above-mentioned Fig. 4, the step S244 includes：

Step S2441, according to postrotational electric current straight line, each PWM count current parameters corresponding to are calculated.

Specifically, as a kind of embodiment, reference picture 6, average current value is represented with the straight line z in statistic histogram Electric current straight line.

Straight line z obtains straight line AB, PWM count is corresponded on straight line AB according to maximum after once single step rotation counterclockwise Current value corresponds to PWM count not less than maximum current value, on straight line AB and is not below minimum current value according to the current value of minimum value.

Cut-off line AB function is y=kx+b, and x is PWM count value, and y is current parameters corresponding to x.

Because center equalization point is point C, abscissa is the PWM count value chosen, and ordinate is average current, then on straight line AB Point C coordinate values known to.

Because the straight line z anglecs of rotation rotated to straight line AB are preset value, then k value can be calculated.And then by point The function that C coordinate value substitutes into straight line AB calculates, and can obtain b value.

Then, calculated due to the k values in function y=kx+b and b values, it is known that each PWM count value is substituted into function as x values, It can obtain corresponding y values, namely current parameters.

Thus, each PWM count current parameters corresponding in statistic histogram, namely the current parameters of each LED are obtained.

Step S2442, it is calculated and each LED is controlled according to each PWM count evidence and corresponding current parameters Driving power.

After each PWM count current parameters corresponding in obtaining statistic histogram, joined according to the electric current of each LED of acquisition Number, calculate the power consumed during LEDs all in driving dot matrix backlight.

Specifically, as a kind of embodiment, take and n LED, the PWM count of each LED are shared in current dot matrix backlight It is worth for PWM1, PWM2, PWM3 ... PWMn, current parameters I1, I2, I3 ... In, rated voltage V, then according to following public Formula calculates driving power P1 during driving dot matrix backlight：

P1=I1 × V × PWM1+I2 × V × PWM2+I3 × V × PWM3+ ... In × V × PWMn.

Thus, obtain according to the driving in each PWM count evidence and corresponding current parameters control dot matrix backlight during each LED Power.

Step S2443, judge whether the driving power reaches the general power.

Obtaining driving in dot matrix backlight after the driving power of each LED, judging when whether forehead driving power reaches The general power being pre-configured with.

Specifically, as a kind of embodiment, the general power being pre-configured with can be configured according to the actual requirements.According to total The value of power, takes default power interval, and the performance number in power interval is to reach the performance number of general power.For example, take power Section is the 90% to 100% of general power, then performance number within this range reaches general power, more than 100% general power or small General power is not up in the performance number of 90% general power.

According to obtained driving power value, judge whether driving power reaches general power.

If driving power value is located within default power interval, judge that driving power reaches general power；If drive work( Rate is located at outside default power interval, then judges that driving power is not reaching to general power.

Thus, result of determination is obtained.

If step S2444, described driving power is not reaching to the general power, returns and perform step：With the center Equalization point is rotary middle point, and single step counterclockwise rotates the electric current straight line；If the driving power reaches the general power, By current parameters corresponding to each PWM count evidence, as the current parameters for controlling each LED and the electric current ginseng is stored Number.

After result of determination is obtained, if driving power is not reaching to general power, control electric current straight line continues to put down with center Weighing apparatus point is pivot, and single step rotation counterclockwise, after rotation, whether the driving TV for judging to obtain again meets general power.

If driving power reaches general power, stop the rotation electric current straight line, and with each electric current of now electric current line correspondences Parameter, the current parameters as each LED in the current parameters of corresponding PWM count evidence, namely control dot matrix backlight.

In the present embodiment, PWM count is calculated each according to conversion calculation processing unit according to postrotational electric current straight line PWM count current parameters corresponding to；According to rated voltage, each PWM count evidence and corresponding current parameters, it is calculated according to each PWM count evidence and corresponding current parameters control the driving power of each LED；Then, judge whether driving power reaches in advance to match somebody with somebody The general power put；If driving power is not reaching to general power, continue using center equalization point as rotary middle point, single step counterclockwise Rotatory current straight line；If driving power reaches general power, by each PWM count corresponding to current parameters, as controlling each LED Current parameters and store current parameters.After the present embodiment is by being calculated the driving power of each LED, determine whether to meet General power, it is unsatisfactory for, continues to adjust the current parameters of each LED, until the driving power according to obtained current parameters configuration Meet the general power of configuration, current parameters now are configured for optimal electric current, and the optimization for realizing each LED power consumption is matched somebody with somebody Put, avoid the waste of the energy, while also ensure that the high image quality of television image.

Reference picture 7, dot matrix backlight driving device first embodiment of the present invention provide a kind of dot matrix backlight driving device, The dot matrix backlight driving device includes：

Image processing module 100, for the TV signal according to input, it is calculated in control dot matrix backlight and each sends out The pulse width modulation (PWM) data of optical diode LED.

Specifically, as a kind of embodiment, after television set starts, the dynamic access TV of image processing module 100 letter The TV signal of every frame television image of number source input.

Then, image processing module 100 according to the quantity of LED array light sources by the television image in frame buffer be divided into LED quantity in LED array light sources is equal, one-to-one picture block.

Thus, image processing module 100 obtains controlling the PWM count evidence of each LED, and obtained PWM count evidence is sent to Driven management module 200.

Driven management module 200, for according to the PWM count evidence, making statistic histogram, and according to the statistics Nogata The current parameters for controlling each LED are calculated in figure.

After driven management module 200 receives the data that image processing module 100 is sent, parse to obtain by suitable by data The PWM count evidence of each LED of position sequence.Then, obtained PWM count evidence is stored.

After the PWM count evidence of each LED in obtaining dot matrix backlight electric power, driven management module 200 is according to obtained PWM count According to, making statistic histogram, and calculate the current parameters of each LED in control dot matrix backlight.

Specifically, as a kind of embodiment, first, driven management module 200 is according to the dot matrix backlight being pre-configured with General power, and rated supply voltage, PWM count evidence, the average current value of LED in dot matrix backlight is calculated, by average electricity Initial current value of the flow valuve as each LED.

Then, driven management module 200 makes statistic histogram according to obtained PWM count evidence.

In electric current straight line rotary course, driven management module 200 calculates according to the postrotational electric current straight line of each single step Each PWM count current parameters corresponding to are obtained, so as to obtain the current parameters of each LED.Then, according to each LED of acquisition Current parameters, calculate the power consumed during all LEDs in control dot matrix backlight.

Thus, driven management module 200 obtains controlling the current parameters of each LED in dot matrix backlight.In this implementation In example, obtained current parameters are current value.

Then, driven management module 200 stores the current parameters of each LED.

Then, the PWM count evidence and current parameters of storage are sent to drive circuit module 300 by driven management module 200.

Drive circuit module 300, for each LED according to the PWM count evidence and the current parameters independent control, Drive the dot matrix backlight.

Drive circuit module 300 receives the PWM count of each LED in the dot matrix backlight that driven management module 200 is sent According to and current parameters, each LED of independent control, drive dot matrix backlight.

Drive circuit module 300, by the PWM on-off circuits of each LED, divides according to the PWM count evidence of each LED of acquisition It is other that PWM controls are carried out to each LED, control the pulse duty cycle of each LED.

Meanwhile drive circuit module 300 passes through the current control of each LED according to the current parameters of each LED of acquisition Circuit, current control is carried out to each LED respectively.

Thus, drive circuit module 300 realizes the driving to dot matrix backlight, shows current television image.

In the present embodiment, first, control dot matrix is calculated according to the TV signal of input in image processing module 100 The pulse width modulation (PWM) data of each LED lamp in backlight；Then, driven management module 200 is according to PWM Data, statistic histogram is made, and the current parameters for controlling each LED are calculated according to statistic histogram；Then, driving electricity Road module 300 each LED of independent control, drives dot matrix backlight according to the PWM count evidence and current parameters of each LED.This reality Example is applied by the PWM count according to acquisition according to statistic histogram is made, so as to adjust the electric current ginseng of each PWM count LED corresponding to Number, realizes and the electric current of all LEDs in dot matrix backlight is all distributed according to need, under conditions of power consumption is ensured, draw TV Face integrally reaches optimal display result, avoids power attenuation and energy waste.

Further, reference picture 8, dot matrix backlight driving device second embodiment of the present invention provide a kind of dot matrix backlight Drive device, based on the embodiment shown in above-mentioned Fig. 7, the PWM count evidence is each LED in the corresponding dot matrix backlight Each PWM count evidence, the driven management module 200 include：

Electric current averaging unit 210, for according to the PWM count evidence and the dot matrix backlight general power, specified being pre-configured with Voltage, calculate the average current of each LED in dot matrix backlight.

After the PWM count evidence of each LED in obtaining dot matrix backlight electric power, driven management module 200 calculates each LED Driving current parameter.

As a kind of embodiment, electric current averaging unit 210 is and specified according to the dot matrix backlight general power being pre-configured with Supply voltage, PWM count evidence, the average current value of LED in dot matrix backlight is calculated, using average current value as each LED The initial current value of lamp.

Specific calculating process is as follows：

Thus, the average current value of LED in dot matrix backlight is obtained.

Histogram production unit 220, for each PWM count evidence of each LED in the corresponding dot matrix backlight, system Take statistics histogram.

Histogram production unit 220 makes statistic histogram according to obtained PWM count evidence.

Electric current straight line units 230, for according to the average current, electric current straight line to be made in the statistic histogram, Each PWM count is according to the current parameters on the corresponding electric current straight line in the statistic histogram.

After statistic histogram is obtained, electric current straight line units 230 make electricity in statistic histogram, according to average current value Flow straight line.Each PWM count is according to the current parameters in corresponding current straight line.

Single step rotary unit 240, the electric current straight line is rotated for single step counterclockwise, and it is straight according to postrotational electric current Line, the current parameters for controlling each LED are calculated.

After electric current straight line is obtained, the rotatory current straight line of single step rotary unit 240, and according to postrotational electric current straight line, The current parameters of each LED in control dot matrix backlight are calculated.

Specifically, as a kind of embodiment, first, by default rule, single step rotary unit 240 is on electric current straight line Obtain the center equalization point of statistic histogram.

In electric current straight line rotary course, single step rotary unit 240 calculates according to the postrotational electric current straight line of each single step Each PWM count current parameters corresponding to are obtained, so as to obtain the current parameters of each LED.

Thus, single step rotary unit 240 obtains controlling the current parameters of each LED in dot matrix backlight.In this implementation In example, obtained current parameters are current value.

Then, single step rotary unit 240 stores the current parameters of obtained each LED.

In the present embodiment, preferred, electric current averaging unit 210 is total according to PWM count evidence and the dot matrix backlight being pre-configured with Power, rated voltage, calculate the average current of each LED in dot matrix backlight；Then, the basis of histogram production unit 220 Each PWM count evidence of corresponding each LED, makes statistic histogram；Then, electric current straight line units 230 are counting according to average current Electric current straight line is made in histogram, each PWM count is according to the current parameters on corresponding current straight line；Then, single step rotary unit 240 is inverse Hour hands single step rotatory current straight line, and according to postrotational electric current straight line, each LED in control dot matrix backlight is calculated Current parameters.The present embodiment determines each LED initial current by the average current of each LED in dot matrix backlight；So Afterwards, current parameters function corresponding to each LED is easy to regulate and control by electric current straight line；During rotate counterclockwise electric current straight line, make The larger LED of PWM count value obtains bigger current value, more bright, and the less LED of PWM count value obtains smaller electric current Value, brightness are lower；By the current parameters of each LED corresponding to the adjustment of rotatory current straight line, so that the power of each LED consumption Meet the general power pre-set.Thus, the present embodiment ensure that the matter of television image while default general power is met Amount, realizes the targets of energy-saving and emission-reduction, green and ensure picture effect simultaneously, improves Consumer's Experience.

Further, reference picture 9, dot matrix backlight driving device 3rd embodiment of the present invention provide a kind of dot matrix backlight Drive device, based on the embodiment shown in above-mentioned Fig. 8, the single step rotary unit 240 includes：

Central point subelement 241, for according to default rule, the statistic histogram to be chosen on the electric current straight line Center equalization point.

First, by default rule, central point subelement 241 obtains the center balance of statistic histogram on electric current straight line Point.

Specifically, as a kind of embodiment, in the counting statistics histogram of central point subelement 241, each PWM count is according in group The quantity of PWM count evidence, the PWM count of whole LEDs is accounted for according to the percentage of total amount.Wherein, each PWM count goes out according to PWM count evidence in group Occurrence number is the quantity of PWM count evidence in data group.

As another embodiment, central point subelement 241 can be chosen on electric current straight line, line segment between point A and point B 2 Along ents, as center equalization point.

Subelement 242 is rotated, for using the center equalization point as rotary middle point, single step counterclockwise to rotate the electric current Straight line, rotary step are default threshold value.

After center equalization point is obtained, rotation subelement 242 is using this center equalization point as pivot, single step counterclockwise Rotatory current straight line.It should be noted that the rotary step that electric current straight line rotates each time is default threshold value, rotary step can Flexibly set according to the demand of processing speed.For example, if desired lifting processing speed, the threshold value of rotary step can be set It is larger；If desired processing accuracy is improved, the threshold value of rotary step can be set smaller.

Border subelement 243, for according to default rated current, the maximum current that each LED is calculated to be joined Number, and control each PWM count current parameters corresponding to be no more than the maximum current parameter and be not less than default minimum Current parameters.

Specifically, as a kind of embodiment, first, border subelement 243 is calculated according to default rated current The maximum current parameter of each LED.

Thus, border subelement 243 obtains each PWM count maximum current parameter and minimum current parameter corresponding to.

When electric current straight line rotates, border subelement 243 controls current parameters corresponding to maximum PWM count value to be less than or equal to Maximum current parameter, you can realize that each PWM count current parameters corresponding to are no more than maximum current parameter；Control minimum PWM count Current parameters corresponding to value are more than or equal to minimum current parameter, you can realize that each PWM count current parameters corresponding to are not less than Minimum current parameter.

Computation subunit 244, for according to postrotational electric current straight line, the electric current for controlling each LED to be calculated Parameter.

After electric current straight line carries out single step rotation every time, computation subunit 244 is straight according to the postrotational electric current of each single step Line, each PWM count current parameters corresponding to are calculated, so as to obtain the current parameters of each LED.

Thus, computation subunit 244 obtains controlling the current parameters of each LED in dot matrix backlight.

Then, computation subunit 244 stores the current parameters of each LED.

In the present embodiment, central point subelement 241 chooses statistic histogram according to default rule on electric current straight line Center equalization point；Then, subelement 242 is rotated using center equalization point as rotary middle point, and single step rotatory current counterclockwise is straight Line；According to default rated current the maximum current parameter of each LED is calculated, and control PWM count in border subelement 243 It is no more than maximum current parameter according to corresponding current parameters and is not less than default minimum current parameter；Computation subunit 244 According to postrotational electric current straight line, each current parameters of LED are calculated in control dot matrix backlight.The present embodiment passes through choosing Center equalization point is taken, rotating shaft is rotated to be with center equalization point, single step rotatory current straight line counterclockwise, makes the bright part of picture more Bright, gloomy part is gloomy, strengthens contrast, while ensure the brightness of LED in rational scope.According to obtained electricity Each LED of driving parameter is flowed, the general power being pre-configured with both had been met, and had improved image quality again.

Further, reference picture 10, dot matrix backlight driving device fourth embodiment of the present invention provide a kind of dot matrix backlight Source drive device, based on the embodiment shown in above-mentioned Fig. 9, the computation subunit 244 includes：

First computation subunit 2441, for according to postrotational electric current straight line, each PWM count to be calculated according to corresponding Current parameters.

The cut-off line AB of first computation subunit 2441 function is y=kx+b, and x is PWM count value, and y is that electric current corresponding to x is joined Number.

Thus, the first computation subunit 2441 obtains each PWM count current parameters corresponding in statistic histogram, namely respectively The current parameters of LED.

Second power subelement 2442, for being joined according to the rated voltage, each PWM count evidence and corresponding electric current Number, the driving power that each LED is controlled according to each PWM count evidence and corresponding current parameters is calculated.

After the current parameters corresponding to of each PWM count in obtaining statistic histogram, the second power subelement 2442 is according to obtaining The current parameters of each LED obtained, calculate the power consumed during LEDs all in driving dot matrix backlight.

Specifically, as a kind of embodiment, the second power subelement 2442, which takes, shares n in current dot matrix backlight LED, the PWM count value of each LED are PWM1, PWM2, PWM3 ... PWMn, current parameters I1, I2, I3 ... In, specified Voltage is V, then driving power P1 during driving dot matrix backlight is calculated according to equation below：

P1=I1 × V × PWM1+I2 × V × PWM2+I3 × V × PWM3+ ... In × V × PWMn.

Thus, the second power subelement 2442 is obtained according to each PWM count evidence and corresponding current parameters control dot matrix backlight Driving power in source during each LED.

3rd judgment sub-unit 2443, for judging whether the driving power reaches the general power.

Obtaining driving in dot matrix backlight after the driving power of each LED, the 3rd judgment sub-unit 2443 judges currently Whether volume driving power reaches the general power being pre-configured with.

3rd judgment sub-unit 2443 judges whether driving power reaches general power according to obtained driving power value.

Thus, the 3rd judgment sub-unit 2443 obtains result of determination.

4th obtains subelement 2444, if reaching the general power for the driving power, by each PWM count evidence Corresponding current parameters, as the current parameters for controlling each LED and store the current parameters.

If driving power meets general power, the 4th acquisition subelement 2444 stops the rotation electric current straight line, and with now electric Each current parameters of line correspondences are flowed, as each in the current parameters of corresponding PWM count evidence, namely control dot matrix backlight The current parameters of LED.

Thus, the 4th acquisition subelement 2444 obtains controlling the current parameters of each LED in dot matrix backlight.

Then, the 4th acquisition subelement 2444 stores the current parameters of each LED.

The rotation subelement 242, if being additionally operable to the driving power is unsatisfactory for the general power, is put down with the center Weighing apparatus point is rotary middle point, and single step counterclockwise rotates the electric current straight line.

After result of determination is obtained, if driving power is not reaching to general power, the control electric current straight line of subelement 242 is rotated Continue using center equalization point as pivot, single step rotation counterclockwise, after rotation, the 3rd judgment sub-unit 2443 judges again Whether obtained driving TV meets general power.

In the present embodiment, each PWM count evidence is calculated according to postrotational electric current straight line in the first computation subunit 2441 Corresponding current parameters；Second power subelement 2442 calculates according to rated voltage, each PWM count evidence and corresponding current parameters Obtain controlling the driving power of each LED according to each PWM count evidence and corresponding current parameters；Then, the 3rd judgment sub-unit 2443 judge whether driving power reaches the general power being pre-configured with；If driving power is not reaching to general power, gyrator list Member 242 continues using center equalization point as rotary middle point, single step rotatory current straight line counterclockwise；If driving power reaches total work Rate, then the 4th obtain subelement 2444 by each PWM count the current parameters corresponding to, as controlling the current parameters of each LED simultaneously Store current parameters.After the present embodiment is by being calculated the driving power of each LED, determine whether to meet general power, be discontented with It is sufficient then continue to adjust the current parameters of each LED, until meeting configuration according to the driving power of obtained current parameters configuration General power, current parameters now configure for optimal electric current, realize the optimization collocation of each LED power consumption, avoid the energy Waste, while also ensure that the high image quality of television image.

Reference picture 11, dot matrix backlight drive system first embodiment of the present invention provide a kind of dot matrix backlight driver system System, the dot matrix backlight drive system include television video image procossing MEMC modules As, LED lamp driving control Management module B processed and LED lamp drive circuit module C, wherein：

The television video image procossing MEMC modules As, for the TV signal according to input, are calculated control dot matrix The pulse width modulation (PWM) data of each LED lamp in backlight；PWM count evidence is sent to the LED Drive control management module B.

After television set starts, TV video processor front end, namely the television video image procossing of central processor CPU MEMC (Motion Estimate and Motion Compensation, Motion estimation and compensation) modules A dynamic access The TV signal of every frame television image of TV signal source input.

Then, television video image procossing MEMC modules As draw the TV in frame buffer according to the quantity of LED array light sources Face is divided into picture block equal with the LED quantity in LED array light sources, one-to-one.

When the PWM count of all LEDs finishes according to calculating, then log-on data sending module immediately, as host computer, first will The data encoding packing of transmission, the LED that LED array light source driving plates are then transmitted data to by spi bus drive control Management module B processed.

The LED drive control management module B, sent for receiving the television video image procossing MEMC modules As The PWM count evidence；According to the PWM count evidence, statistic histogram is made, and control is calculated according to the statistic histogram The current parameters of each LED；The PWM count evidence and the current parameters are sent to the LED lamp drive circuit module C。

LED drive control management module B is located at the driving plate of LED array light sources, for receiving at television video image The PWM count evidence that MEMC modules As are sent is managed, is analyzed and is calculated, obtain the optimum current control of each LED in dot matrix backlight Parameter processed, and PWM count evidence and current parameters are sent to LED lamp drive circuit module C.

After LED drive control management module B receptions parse each PWM count evidence that host computer is sent, it is divided into two Part uses and handled the data.Part I is according to the address mapping relation table according to corresponding LED directly by each PWM count The driving PWM registers of each LED are accurately write, to determine the switch time of each LED；Another part is then for calculating The current parameters of each LED, namely current value, the current value of each LED is then written to corresponding current control and posted In storage.

For example, the dot matrix backlight for configuring 288 LED lamps, real by the dot matrix backlight drive method of the present invention Example is applied, calculates the current value that each LED matches with its PWM duty cycle, is then written to this 288 current values corresponding In the current control register of 288 LEDs, each LED is set to have a current control value, so as to change prior art All LEDs or same group of LED of regional area is allowed not only to improve picture effect all using the way of same current value Fruit and it also avoid power attenuation and energy waste.

Specifically, as a kind of embodiment, first, LED drive control management module B is by PWM count according to being converted into pair The current parameters for each LED answered.Then LED drive control management module B passes through obtained each LED current parameters Spi bus flushes to current driving circuit corresponding to each LED, to control the current value size of each LED.

Meanwhile LED drive control management module B directly flushes to received PWM count respectively according to by spi bus PWM ON-OFF control circuits corresponding to LED, to adjust the contactor time of each LED.

So, the PWM duty cycle of each LED and conducting electric current is allowed can freely to set.

Wherein, LED drive control management module B is specific according to the current parameters for being converted into corresponding each LED by PWM count Calculating process, to configure the dot matrix backlight of 288 LED lamps, it is illustrated.

Television set is allocated to power workable for the work of all LEDs on LED dot matrix backlight driver plates 420W, namely the general power of configuration is 420W.

Because the supply voltage that LED adds wire is 9V, namely rated voltage is 9V, then all LED normal works Workable maximum current is 420/9 ≈ 47A.

In the case of the PWM count of all LEDs is according to being all 100% dutycycle, the setting electric current of each LED can not surpass 47A/288*100%=163mA is crossed, otherwise can make whole dot matrix backlight driver plate exceedes dispensing using power.And for One abundant in content natural picture, not every PWM count is according to being all 100%, but various composition has, at this moment if Or using unified electric current configuration mode, then picture can be made to have not dark enough universal in bright place is not bright enough, this is dark place Situation.The region of especially dark picture, the electric current of lamp is also that configuration is very high, causes unnecessary waste.Due to each LED most Big rated current can arrive 340mA, and bright place is not big enough because electric current is defined, and makes light-source brightness inabundant Use.

In the case where driving power is no more than general power, in order to make each LED be assigned to optimum amounts of current, The PWM count of each LED received is by LED drive control management module B according to a statistic histogram, abscissa is established PWM count evidence, namely dutycycle, ordinate are the quantity of LED.Larger electric current is distributed for the LED of high duty ratio, makes this A little LEDs are luminous most strong, such as 100% is assigned to and is up to 340mA, the relatively low current value of the distribution for low duty ratio, Make these LEDs coordinate image content to light dark, by that analogy, the situation of the general power of configuration is no more than in driving power Under, the current value of all LEDs is calculated, so as to complete to coordinate picture actual content distribution according to need electric current, is imitated so as to maximum Rate make use of LED light source and power.

The LED lamp drive circuit module C, for receiving described in the LED drive control management module B transmissions PWM count evidence and the electric current；According to each LED described in the PWM count evidence and the current parameters independent control, the point is driven Battle array backlight.

The drive circuit module C of LED receives each in the dot matrix backlight that LED drive control management module B is sent The PWM count evidence and current parameters of LED, each LED of independent control, drive dot matrix backlight.

The drive circuit module C of LED switchs electricity according to the PWM count evidence of each LED of acquisition by the PWM of each LED Road, PWM controls are carried out to each LED respectively, control the pulse duty cycle of each LED.

Meanwhile the drive circuit module C of LED passes through the electricity of each LED according to the current parameters of each LED of acquisition Flow control circuit, current control is carried out to each LED respectively.

Thus, the drive circuit module C of LED realizes the driving to dot matrix backlight, shows current television image.

In the present embodiment, dot matrix backlight drive system by television video image procossing MEMC modules As according to input TV signal, the pulse width modulation (PWM) data of each LED lamp in control dot matrix backlight are calculated； Then LED drive control management module B makes statistic histogram, and calculate and control according to statistic histogram according to PWM count evidence The current parameters of each LED in dot matrix backlight；Then, LED lamp drive circuit module C is according to obtained PWM count evidence and electricity Flow parameter, the PWM and electric current of each LED of independent control, so as to drive dot matrix backlight.The present embodiment is realized to dot matrix backlight The independent control of each LED in source, coordinates the actual content distribution according to need electric current of television image, and maximal efficiency make use of LED Light source and power.

Further, reference picture 12, backlight drive system second embodiment of the present invention provide a kind of backlight driver system System, based on the embodiment shown in above-mentioned Figure 11, the LED drive control management module B includes serial peripheral equipment interface SPI bus Data receipt unit B1, SPI receive data buffer B2, central cpu processing unit B3, PWM count according to conversion calculation processing unit B4, SPI send data buffer B5 and spi bus data transmission unit B6, wherein：

The spi bus data receipt unit B1, for receiving the television video image procossing MEMC modules As transmission PWM count evidence.

In the present embodiment, LED drive control management module B is located in the driving plate of LED array light sources, passes through SPI (Serial Peripheral Interface, Serial Peripheral Interface (SPI)) bus and television video image procossing MEMC modules As and LED lamp drive circuit module C is interacted.

PWM count evidence is calculated in television video image procossing MEMC modules As, PWM count is sent out according to packing and by spi bus After the driving plate for giving LED array light sources, spi bus data receipt unit B1 receives television video image procossing MEMC modules As The PWM count of transmission is according to bag.

The PWM count that central cpu processing unit B3 parses to obtain obtains PWM count according to each PWM count evidence in bag according to bag.

The SPI receives data buffer B2, for storing the PWM count evidence.

After the PWM count evidence of television video image procossing MEMC modules As transmission is obtained, SPI receives data buffer B2 and deposited Obtained PWM count evidence is stored up, for follow-up Data Analysis Services.

The central cpu processing unit B3, for controlling, coordinating the processing of the PWM count evidence.

Central cpu processing unit B3 is used for the work for controlling, coordinating each unit in LED drive control management module B.

Specifically, central cpu processing unit B3 control spi bus data receipt units B1 receives television video image procossing The PWM count that MEMC modules As are sent is according to bag.

Then, central cpu processing unit B3 parses PWM count and obtains the PWM count evidence respectively to be sorted by cis-position according to bag, and will be each PWM count receives data buffer B2 according to deposit SPI.

Then, central cpu processing unit B3 by each PWM count according to be sent to PWM count according to conversion calculation processing unit B4, by The current parameters of each LED, and each LED electric current that will be obtained are calculated according to conversion calculation processing unit B4 processing for PWM count Parameter deposit SPI sends data buffer.

Thus, obtain controlling the PWM count evidence and current parameters of each LED.

Then, central cpu processing unit control spi bus data transmission unit B6 joins the PWM count evidence and electric current of storage Number is sent to the drive circuit module C of each LED, to control each LED.

The PWM count is according to conversion calculation processing unit B4, for according to the PWM count evidence, making statistic histogram, and root The current parameters for controlling each LED are calculated according to the statistic histogram.

PWM count is obtaining PWM corresponding to the LED of central cpu processing unit B3 transmissions according to conversion calculation processing unit B4 After data, statistic histogram is made, the corresponding current parameters for controlling each LED are calculated.

Specifically, as a kind of embodiment, first, PWM count according to conversion calculation processing unit B4 according to each PWM count evidence and Dot matrix backlight general power, the rated voltage being pre-configured with, calculate the average current of each LED in dot matrix backlight.

Then, each PWM count evidence of each LED in corresponding dot matrix backlight, makes statistic histogram, obtains PWM The distribution situation of data.

Then, PWM count is made according to conversion calculation processing unit B4 according to the average current of each LED in statistic histogram Make electric current straight line, each PWM count is according to the current parameters on corresponding current straight line in statistic histogram.

Then, according to default rule, the center equalization point of statistic histogram is chosen on electric current straight line, this center balances The coordinate of point is, it is known that and keep constant.

Then, using the center equalization point of selection as rotary middle point, single step rotatory current straight line counterclockwise, rotary step is Default threshold value.For rotatory current straight line so that current parameters corresponding to larger PWM count value are bigger, less PWM count value is corresponding Current parameters it is smaller so that television image it is bright part it is brighter, gloomy part is more gloomy, strengthens contrast.

In rotary course, the boundary value of current parameters corresponding to PWM count value is controlled, so that each PWM count electricity corresponding to Stream parameter is no more than maximum current value, not less than minimum current value, ensures the brightness of picture in the reasonable scope.

Then, according to the electric current straight line obtained after rotation, the current parameters for controlling each LED are calculated.And root According to obtained current parameters, whether the power for judging to consume during according to obtained current parameters driving dot matrix backlight meets to preset General power.

If the power of consumption is unsatisfactory for default general power, continue rotatory current straight line；If the power of consumption meets pre- If general power, then according to the current parameters that now obtain, as the current parameters of corresponding each LED, and by current parameters It is sent to SPI and sends data buffer B5.

The SPI sends data buffer B5, for storing the current parameters.

SPI sends data buffer B5 and receives PWM count according to electricity corresponding to each LED of conversion calculation processing unit B4 transmissions Parameter is flowed, and is stored.

The spi bus data transmission unit B6, it is described for the PWM count evidence and the current parameters to be sent to LED lamp drive circuit module C.

The PWM count evidence and current parameters of storage are sent respectively to corresponding each LED by spi bus data transmission unit B6 Lamp.

Specifically, as a kind of embodiment, spi bus data transmission unit B6 closes according to the address of cache of each LED It is table, by each PWM count according to the driving PWM registers for accurately writing each LED, to determine the switch time of each LED

The current value of each LED is written to corresponding current control register by spi bus data transmission unit B6 In.Such as：Dot matrix backlight for configuring 288 LEDs, is calculated by dot matrix backlight drive method provided by the invention Go out each LED and its PWM count evidence, namely the current value of dutycycle matching, then starting spi bus data transmission unit B6 will This 288 current values are written in the current control register of corresponding 288 LEDs, each lamp is had an electric current control Value processed.

In the present embodiment, LED drive control management module B includes spi bus data receipt unit, SPI receives number According to buffer, central cpu processing unit, PWM count data buffer and spi bus number are sent according to conversion calculation processing unit, SPI According to transmitting element, realize and receive the PWM count evidence that television video image procossing MEMC modules As are sent；And according to PWM count evidence, system Take statistics histogram, and the current parameters of each LED in control dot matrix backlight are calculated according to statistic histogram；So Afterwards, PWM count evidence and current parameters are sent to LED lamp drive circuit module C.The present embodiment change prior art allow it is all LED or same group of LED of regional area all use the way of same current value, realize to owning in dot matrix backlight The electric current of LED is all distributed according to need, and under conditions of power consumption is ensured, television image is integrally reached optimal display result, is avoided Power attenuation and energy waste.

The preferred embodiments of the present invention are these are only, are not intended to limit the scope of the invention, it is every to utilize this hair The equivalent structure or equivalent flow conversion that bright specification and accompanying drawing content are made, or directly or indirectly it is used in other related skills Art field, is included within the scope of the present invention.

Claims

1. a kind of dot matrix backlight drive method, it is characterised in that the dot matrix backlight drive method comprises the following steps：

According to the TV signal of input, each pulse width of LED lamp is calculated in control dot matrix backlight Modulation (PWM) data；

According to the PWM count evidence, statistic histogram is made, and control each LED is calculated according to the statistic histogram The current parameters of lamp；

According to each LED described in the PWM count evidence and the current parameters independent control, the dot matrix backlight is driven；

The described the step of current parameters for controlling each LED are calculated according to the statistic histogram, includes：

Electric current straight line is made in the statistic histogram, each PWM count is according to the corresponding electric current straight line in the statistic histogram On current parameters；

Single step counterclockwise rotates the electric current straight line, and according to postrotational electric current straight line, control each LED is calculated Current parameters.

2. dot matrix backlight drive method as claimed in claim 1, it is characterised in that the PWM count evidence is the corresponding point Each PWM count evidence of each LED in battle array backlight, it is described according to the PWM count evidence, statistic histogram is made, and according to described Statistic histogram, which is calculated the step of current parameters for controlling each LED, to be included：

According to the PWM count evidence and the dot matrix backlight general power, the rated voltage that are pre-configured with, calculate each in dot matrix backlight The average current of LED；

According to the average current, electric current straight line is made in the statistic histogram, each PWM count evidence in the statistic histogram Current parameters on the corresponding electric current straight line；

3. dot matrix backlight drive method as claimed in claim 2, it is characterised in that the single step counterclockwise rotates the electricity The step of flowing straight line, and according to postrotational electric current straight line, the current parameters for controlling each LED are calculated includes：

Using the center equalization point as rotary middle point, single step counterclockwise rotates the electric current straight line, and rotary step is default Threshold value；

According to default rated current, the maximum current parameter of each LED is calculated, and controls each PWM count evidence Corresponding current parameters are no more than the maximum current parameter and are not less than default minimum current parameter；

4. dot matrix backlight drive method as claimed in claim 3, it is characterised in that described straight according to postrotational electric current Line, the step of controlling the current parameters of each LED in dot matrix backlight, which is calculated, to be included：

According to the rated voltage, each PWM count evidence and corresponding current parameters, it is calculated according to each PWM count evidence The driving power of each LED is controlled with corresponding current parameters；

Judge whether the driving power reaches the general power；

If the driving power is not reaching to the general power, returns and perform step：Using the center equalization point as in rotation Heart point, single step counterclockwise rotate the electric current straight line, and rotary step is default threshold value；

If the driving power reaches the general power, by each PWM count corresponding to current parameters, as described in control The current parameters of each LED simultaneously store the current parameters.

5. a kind of dot matrix backlight driving device, it is characterised in that the dot matrix backlight driving device includes：

Image processing module, for the TV signal according to input, each light-emitting diodes in control dot matrix backlight are calculated The pulse width modulation (PWM) data of pipe LED；

Driven management module, for according to the PWM count evidence, making statistic histogram, and calculate according to the statistic histogram Obtain controlling the current parameters of each LED；

Drive circuit module, for each LED according to the PWM count evidence and the current parameters independent control, drive institute State dot matrix backlight；

The driven management module, it is additionally operable to make electric current straight line in the statistic histogram, it is each in the statistic histogram PWM count is according to the current parameters on the corresponding electric current straight line；Single step counterclockwise rotates the electric current straight line, and according to postrotational Electric current straight line, the current parameters for controlling each LED are calculated.

6. dot matrix backlight driving device as claimed in claim 5, it is characterised in that the PWM count evidence is the corresponding point Each PWM count evidence of each LED in battle array backlight, the driven management module include：

Electric current averaging unit, for according to the PWM count evidence and the dot matrix backlight general power, the rated voltage that are pre-configured with, meter Calculate the average current of each LED in dot matrix backlight；

Histogram production unit, for each PWM count evidence of each LED in the corresponding dot matrix backlight, make statistics Histogram；

Electric current straight line units, for according to the average current, electric current straight line, the statistics to be made in the statistic histogram Each PWM count is according to the current parameters on the corresponding electric current straight line in histogram；

Single step rotary unit, the electric current straight line is rotated for single step counterclockwise, and according to postrotational electric current straight line, calculated To the current parameters for controlling each LED.

7. dot matrix backlight driving device as claimed in claim 6, it is characterised in that the single step rotary unit includes：

Central point subelement, for according to default rule, choosing the center of the statistic histogram on the electric current straight line Equalization point；

Subelement is rotated, for using the center equalization point as rotary middle point, single step counterclockwise to rotate the electric current straight line, rotation It is default threshold value to turn step-length；

Border subelement, for according to default rated current, the maximum current parameter of each LED being calculated, and control Each PWM count current parameters corresponding to are made to be no more than the maximum current parameter and not less than default minimum current join Number；

Computation subunit, for according to postrotational electric current straight line, the current parameters for controlling each LED to be calculated.

8. dot matrix backlight driving device as claimed in claim 7, it is characterised in that the computation subunit includes：

First computation subunit, for according to postrotational electric current straight line, each PWM count electric current ginseng corresponding to be calculated Number；

Second power subelement, for according to the rated voltage, each PWM count evidence and corresponding current parameters, calculating To the driving power that each LED is controlled according to each PWM count evidence and corresponding current parameters；

4th obtains subelement, if reaching the general power for the driving power, by electricity corresponding to each PWM count evidence Parameter is flowed, as the current parameters for controlling each LED and stores the current parameters；

The rotation subelement, if being additionally operable to the driving power is not reaching to the general power, with the center equalization point For rotary middle point, single step counterclockwise rotates the electric current straight line.

9. a kind of dot matrix backlight drive system, it is characterised in that the dot matrix backlight drive system includes television video figure As processing MEMC modules, LED lamp drive control management module and LED lamp drive circuit module, wherein：

The television video image procossing MEMC modules, for the TV signal according to input, control dot matrix backlight is calculated The pulse width modulation (PWM) data of each LED lamp in source；The PWM count is driven according to the LED is sent to Control management module；

The LED drive control management module, for receiving described in the television video image procossing MEMC modules transmission PWM count evidence；According to the PWM count evidence, statistic histogram is made, and it is described each according to the statistic histogram control to be calculated The current parameters of LED；The PWM count evidence and the current parameters are sent to the LED lamp drive circuit module；

The LED lamp drive circuit module, the PWM count evidence sent for receiving the LED drive control management module With the electric current；According to each LED described in the PWM count evidence and the current parameters independent control, the dot matrix backlight is driven Source；

The LED drive control management module, it is additionally operable to make electric current straight line in the statistic histogram, the statistics is straight Each PWM count is according to the current parameters on the corresponding electric current straight line in square figure；The single step rotation counterclockwise electric current straight line, and according to Postrotational electric current straight line, the current parameters for controlling each LED are calculated.

10. backlight drive system as claimed in claim 9, it is characterised in that the LED drive control management module bag Include serial peripheral equipment interface SPI bus data receiving unit, SPI receives data buffer, central cpu processing unit, PWM count evidence turn Calculation processing unit, SPI transmission data buffers and spi bus data transmission unit are changed, wherein：

The spi bus data receipt unit, the PWM count sent for receiving the television video image procossing MEMC modules According to；

The SPI receives data buffer, for storing the PWM count evidence；

The PWM count is according to conversion calculation processing unit, for according to the PWM count evidence, making statistic histogram, and according to described The current parameters for controlling each LED are calculated in statistic histogram；

The SPI sends data buffer, for storing the current parameters；

The spi bus data transmission unit, driven for the PWM count evidence and the current parameters to be sent into the LED Dynamic circuit module.