CN202035086U - Self-voltage-stabilization enable control circuit, voltage boost drive circuit, and television set - Google Patents
Self-voltage-stabilization enable control circuit, voltage boost drive circuit, and television set Download PDFInfo
- Publication number
- CN202035086U CN202035086U CN2011200652755U CN201120065275U CN202035086U CN 202035086 U CN202035086 U CN 202035086U CN 2011200652755 U CN2011200652755 U CN 2011200652755U CN 201120065275 U CN201120065275 U CN 201120065275U CN 202035086 U CN202035086 U CN 202035086U
- Authority
- CN
- China
- Prior art keywords
- resistance
- voltage
- circuit
- voltage stabilizing
- control circuit
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Images
Landscapes
- Dc-Dc Converters (AREA)
Abstract
The utility model discloses a self-voltage-stabilization enable control circuit, a voltage boost drive circuit, and a television set, relates to the field of voltage stabilization circuits, and is designed for stably controlling the voltage of an enable pin on a voltage boost control chip. The self-voltage-stabilization enable control circuit comprises a self-voltage-stabilization regulating circuit, which comprises a three-terminal adjustable shunt reference source, a first resistor and a second resistor, wherein the anode of the three-terminal adjustable shunt reference source is connected with the first resistor, the anode is grounded, the cathode of the three-terminal adjustable shunt reference source is connected with the second resistor, the cathode is the output terminal of the three-terminal adjustable shunt reference source, the first resistor is connected with the second resistor, and the reference terminal of the three-terminal adjustable shunt reference source is connected with the first resistor and the second resistor. The utility model also provides the voltage boost drive circuit and the television set that use the self-voltage-stabilization enable control circuit. The self-voltage-stabilization enable control circuit can be used for providing the voltage boost control chip with a stable enable pin voltage.
Description
Technical field
The utility model relates to a kind of voltage stabilizing circuit, relates in particular to a kind ofly to enable control circuit, booster driving circuit and television set from voltage stabilizing.
Background technology
In the backlight control circuit of liquid crystal displays such as LCD TV, often use boost control chip, boost control chip is used to the circuit voltage that raises.Boost control chip is provided with enable pin, and when this enable pin conducting, when also promptly obtaining corresponding conducting voltage on this enable pin, boost control chip just can work on power.Therefore in control circuit, need provide stable enable voltage for boost control chip.
For stable enable voltage is provided to boost control chip, traditional control mode is to utilize voltage-stabiliser tube.Voltage-stabiliser tube is connected in the power supply circuits, because voltage-stabiliser tube is operated in the reverse breakdown district, when arriving critical breakdown point, the backward resistance of voltage-stabiliser tube is reduced to a very little value.Though electric current changes in the low-resistance region of a very little value and be reduced at this backward resistance, it is constant that the voltage at voltage-stabiliser tube two ends keeps.According to this specific character, voltage-stabiliser tube can be used as the enable voltage that pressurizer is controlled pin.
State in realization and utilize voltage-stabiliser tube to come in the process of voltage of control chip enable pin, the inventor finds that there are the following problems at least in the prior art: the enable voltage ratio of precision of the enable pin of boost control chip is higher, with the NCL30131-D in the NCL30131 boost control chip series is example, the effective range of the enable voltage of its enable pin is between the 2.7V-3.4V, and adopt the power supply circuits stability of voltage-stabiliser tube poor, therefore can not offer the stable voltage of enable pin, be easy to cause chip can occur in the course of the work powering on suddenly like this or misoperation such as outage.
The utility model content
Embodiment of the present utility model provides a kind of and enables control circuit, booster driving circuit and television set from voltage stabilizing, to realize the stable control of enable pin voltage on the boost control chip.
For achieving the above object, embodiment of the present utility model adopts following technical scheme:
A kind ofly enable control circuit, it is characterized in that, comprise, describedly comprise the adjustable shunting a reference source of three ends, first resistance, second resistance from the voltage stabilizing regulating circuit from the voltage stabilizing regulating circuit from voltage stabilizing, wherein,
The adjustable shunting a reference source of described three ends anode is connected to described first resistance, and described plus earth, the adjustable shunting a reference source of described three ends negative electrode is connected to described second resistance, and described negative electrode is the output of the adjustable shunting a reference source of described three ends, described first resistance is connected with described second resistance, and the adjustable shunting a reference source of described three ends reference edge connects described first resistance and described second resistance.
In addition, describedly enable control circuit from voltage stabilizing and can also comprise the control switch circuit, described control switch circuit comprises triode, described transistor base is connected to the mainboard control switch, described transistor collector is connected to and describedly enables the DC input voitage source of control circuit from voltage stabilizing, and described transistor emitter is connected to described negative electrode.
Described control switch circuit can also comprise filter circuit, and described filter circuit comprises the 3rd resistance and the electric capacity that is connected in parallel, described the 3rd resistance that is connected in parallel and electric capacity one end ground connection, and the other end is connected to described base stage;
Can be connected with first current-limiting resistance between described base stage and the described mainboard control switch; And/or
Can be connected with second current-limiting resistance between described collector electrode and the described DC input voitage source.
Can be connected with the 3rd current-limiting resistance between described transistor emitter and the adjustable shunting a reference source of the described three ends negative electrode.
Wherein, described triode can be NPN type triode.
And the pass between the output voltage of the adjustable shunting a reference source of described three ends and described first resistance and described second resistance is Vout=Vref (1+R2/R1).
A kind of booster driving circuit, comprise and aforesaidly enable control circuit and boost control chip from voltage stabilizing, the described output that enables control circuit from voltage stabilizing is connected to the enable pin of described boost control chip, wherein, can be connected with the 4th current-limiting resistance between the enable pin of described output and described boost control chip.
Described booster driving circuit is to drive the employed booster driving circuit of backlight in the liquid crystal display.
A kind of television set comprises booster driving circuit, and described booster driving circuit comprises as above-mentioned and enable control circuit and boost control chip from voltage stabilizing, and the described output that enables control circuit from voltage stabilizing is connected to the enable pin of described boost control chip.
And described television set comprises backlight, and described backlight connects described booster driving circuit.
The utility model embodiment provides a kind of and has enabled control circuit, booster driving circuit and television set from voltage stabilizing, comprises from the voltage stabilizing regulating circuit.Describedly comprise the adjustable shunting a reference source of three ends from the voltage stabilizing regulating circuit, and as can be known according to the characteristic of the adjustable shunting a reference source of three ends itself, inside in the adjustable shunting a reference source of described three ends has an a reference source Vref, the magnitude of voltage that is to say the adjustable shunting a reference source of described three ends reference edge is Vref always, and the plus earth of the adjustable shunting a reference source of described three ends, and described first resistance is connected between described reference edge and the anode, therefore after the work of the adjustable shunting a reference source of described three ends, the voltage at the first resistance two ends is the voltage Vref of described reference edge.Because the adjustable shunting a reference source of described three ends negative electrode is connected to described second resistance, and described reference edge connects described first resistance and described second resistance, so described cathode voltage is the described first resistance both end voltage and the second resistance both end voltage sum.Because the voltage at the described first resistance two ends is fixed, therefore according to voltage divider principle, regulate the resistance R1 of described first resistance and the resistance R2 of described second resistance respectively, just can obtain the cathode voltage of different value, described negative electrode is the output of the adjustable shunting a reference source of described three ends, so output voltage V out is described cathode voltage.Concrete analysis, output voltage V out=(1+R2/R1) Vref.After the resistance R2 of the resistance R1 of described first resistance and described second resistance determined, the magnitude of voltage of described output voltage had also just had exact value, and stablizes constant.Describedly described output voltage is transferred to the enable pin of boost control chip, thereby can provide stable enable voltage, and can not make boost control chip the situation of misoperation occur for boost control chip from the voltage stabilizing regulating loop.
Description of drawings
Fig. 1 enables the schematic diagram of control circuit from voltage stabilizing for the utility model embodiment;
Fig. 2 is to the improvement schematic diagram that enables control circuit from voltage stabilizing shown in Figure 1;
Fig. 3 is to the further improvement schematic diagram that enables control circuit from voltage stabilizing shown in Figure 1;
Fig. 4 is the schematic diagram of the utility model embodiment booster driving circuit.
Reference numeral:
1-is from the voltage stabilizing regulating circuit, shunting a reference source that 10-three ends are adjustable, and 11-first resistance,
12-second resistance, A-three ends are adjustable shunting a reference source anode,
B-three ends are adjustable shunting a reference source negative electrode, C-three ends are adjustable shunting a reference source reference edge,
2-control switch circuit, the 21-triode, the D-transistor base, the E-transistor collector,
The F-transistor emitter, 22-mainboard control switch, 23-DC input voitage source,
The 24-filter circuit, 241-the 3rd resistance, 242-electric capacity, 31-first current-limiting resistance,
32-second current-limiting resistance, 33-the 3rd current-limiting resistance, 34-the 4th current-limiting resistance,
The 3-boost control chip, the 30-enable pin.
Embodiment
Below in conjunction with accompanying drawing the utility model embodiment is enabled control circuit and booster driving circuit is described in detail from voltage stabilizing.
Should be clear and definite, described embodiment only is a part of embodiment of the present utility model, rather than whole embodiment.Based on the embodiment in the utility model, those of ordinary skills are not making all other embodiment that obtained under the creative work prerequisite, all belong to the scope of the utility model protection.
As shown in Figure 1, enable a specific embodiment of control circuit from voltage stabilizing for the utility model.Enable control circuit from voltage stabilizing described in the present embodiment, comprise, comprise the adjustable shunting a reference source 10 of three ends, first resistance 11, second resistance 12 from voltage stabilizing regulating circuit 1 from voltage stabilizing regulating circuit 1, wherein,
The anode A of shunting a reference source 10 that three ends are adjustable is connected to first resistance 11, and anode A ground connection, the negative electrode B of shunting a reference source 10 that three ends are adjustable is connected to second resistance 12, and negative electrode B is the output of the adjustable shunting a reference source 10 of three ends, first resistance 11 is connected with second resistance 12, and three ends are adjustable, and shunting a reference source reference edge C connects first resistance 11 and second resistance 12.
The utility model embodiment provides a kind of and has enabled control circuit from voltage stabilizing, comprises from voltage stabilizing regulating circuit 1.Comprise the adjustable shunting a reference source 10 of three ends from voltage stabilizing regulating circuit 1, and according to the characteristic of the adjustable shunting a reference source of three ends 10 itself as can be known, has an a reference source Vref in the inside of the adjustable shunting a reference source 10 of three ends, the magnitude of voltage that is to say described reference edge C is Vref always, and anode A ground connection, and first resistance 11 is connected between reference edge C and the anode A, and therefore after adjustable shunting a reference source 10 work of three ends, the voltage at first resistance, 11 two ends is the voltage Vref of reference edge.Because negative electrode B is connected to second resistance 12, and reference edge C connects first resistance 11 and second resistance 12, so negative electrode B voltage is first resistance, 11 both end voltage and second resistance, 12 both end voltage sums.Because the voltage at first resistance, 11 two ends is fixed, therefore according to voltage divider principle, regulate the resistance R1 of first resistance 11 and the resistance R2 of second resistance 12 respectively, just can obtain the negative electrode B voltage of different value, negative electrode B is the output of the adjustable shunting a reference source 10 of three ends, so output voltage V out is negative electrode B voltage.Concrete analysis, output voltage V out=(1+R2/R1) Vref.After the resistance R2 of the resistance R1 of first resistance 11 and second resistance 12 determined, the magnitude of voltage of described output voltage had also just had exact value, and stablizes constant.From voltage stabilizing regulating loop 1 described output voltage is transferred to the enable pin of boost control chip, thereby can provide stable enable voltage, and can not make boost control chip the situation of misoperation occur for boost control chip.
As shown in Figure 2, enabling control circuit from voltage stabilizing and also comprise control switch circuit 2 among the utility model embodiment, control switch circuit 2 comprises triode 21, the base stage D of triode 21 is connected to mainboard control switch 22, the collector electrode E of triode 21 is connected to the DC input voitage source 23 that enables control circuit from voltage stabilizing, and the emitter F of triode 21 is connected to negative electrode B.
In the present embodiment, triode 21 can be NPN type triode.
Triode 21 plays switch, because base stage D is connected to mainboard control switch 22, so can control according to the closed and disconnected of mainboard control switch 22 and voltage to be provided whether for base stage D, thereby determine whether the voltage transmission in DC input voitage source 23 to from voltage stabilizing regulating circuit 1.Mainboard control switch 22 can provide the mainboard working signal, and when mainboard control switch 22 closures, provide a high level voltage signal to base stage D, thereby make collector electrode E and emitter F conducting, and then triode 21 conductings.After triode 21 conductings, the DC input voitage that DC input voitage source 23 provides enters from voltage stabilizing regulating circuit 1.Wherein, in the backlight control circuit of LCD TV, this backlight control circuit can provide the voltage of 12V, and with the work of supply mainboard, the voltage of described 12V can also be simultaneously as the DC input voitage source 23 that enables control circuit from voltage stabilizing.In the present embodiment, what collector electrode E connected promptly is the 12V voltage source of backlight control circuit.When mainboard control switch 22 disconnects, do not have the voltage input on the base stage D, thereby triode 21 turn-offs, the DC input voitage that collector electrode E connects can not be transferred to from voltage stabilizing regulating circuit 1.
As shown in Figure 3, on the basis of above-mentioned control switch circuit 2, control switch circuit 2 can also comprise filter circuit 24, and filter circuit 24 comprises the 3rd resistance 241 and the electric capacity 242 that is connected in parallel, the 3rd resistance 241 that is connected in parallel and electric capacity 242 1 end ground connection, the other end is connected to base stage D.Because filter circuit 24 has an end to be connected to base stage D, and base stage D is connected to mainboard control switch 22, so being voltage signals that mainboard control switch 22 is provided, the effect of filter circuit 24 can provide galvanic current to press by filter circuit 24 to base stage D, in actual applications, when mainboard control switch 22 unexpected closures or other emergency case occur, might form peak voltage etc., can make described voltage signal stable level and smooth by filter circuit 24 this moment.Filter circuit 24 specifically constantly charges by electric capacity 242 and discharge process is finished filtering, and the positive pole of electric capacity 242 connects base stage D, minus earth.
It can also be seen that by Fig. 3, can be connected with first current-limiting resistance 31 between base stage D and the mainboard control switch 22, second current-limiting resistance 32 can be connected with between collector electrode E and the DC input voitage source 23, the 3rd current-limiting resistance 33 can be connected with between emitter F and the negative electrode B.It is not necessary that these three current-limiting resistances enable in the control circuit from voltage stabilizing at this, only plays metering function.Also just because of described current-limiting resistance has been a metering function, therefore the resistance value of described current-limiting resistance can not be very big, otherwise can divide to fall too much voltage, influences this enables control circuit from voltage stabilizing operate as normal.
In the utility model embodiment, describedly enable the adjustable shunting a reference source of three ends in the control circuit from voltage stabilizing to choose TL431 be that example describes.Described TL431 inside has a reference source of a 2.5V, that is to say that reference edge C has the constant voltage of 2.5V.About from the narration of voltage stabilizing regulating circuit 1 as can be known, first resistance 11 is connected between the reference edge C and anode A of described TL431 from above, anode A ground connection, and therefore after described TL431 worked, the voltage at first resistance, 11 two ends was the voltage 2.5V of reference edge C.The voltage of negative electrode B is first resistance, 11 both end voltage and second resistance, 12 both end voltage sums, and negative electrode B is the output of described TL431, according to voltage divider principle, and output voltage V out=Vref (1+R2/R1)=2.5 (1+R2/R1).For described TL431,2.5V＜Vout≤36V, promptly the output voltage of described TL431 can be exported any value in 2.5V to the 36V scope by the ratio of regulating first resistance 11 and second resistance 12.
Comprehensive above about control switch circuit 2 with from the analysis of voltage stabilizing regulating circuit 1, after mainboard control switch 22 closures, triode 21 conductings, the 12V DC input voitage that DC input voitage source 23 provides enter by described TL431, first resistance 11, second resistance 12, the 3rd current-limiting resistance 33 form from voltage stabilizing regulating circuit 1.After the DC input voitage of 12V imports, be carried in anode A, negative electrode B and the reference edge C of described TL431 by the biasing dividing potential drop of the 3rd current-limiting resistance 33, first resistance 11 and second resistance 12, a reference source regulating characteristics by described TL431 self loop that makes the voltage of negative electrode B of described TL431 form by first resistance 11 and second resistance 12 reaches balance then, thereby exports stable voltage.
The utility model also provides a kind of booster driving circuit.As shown in Figure 4, be a specific embodiment of the utility model booster driving circuit.In the present embodiment, described booster driving circuit comprises from voltage stabilizing and enables control circuit and boost control chip 3, and the described output that enables control circuit from voltage stabilizing is connected to the enable pin 30 of boost control chip 3.Referring to shown in Figure 1, enabling control circuit from voltage stabilizing described in the present embodiment comprises from voltage stabilizing regulating circuit 1, comprise the adjustable shunting a reference source 10 of three ends from voltage stabilizing regulating circuit 1, first resistance 11, second resistance 12, wherein, the anode A of shunting a reference source 10 that three ends are adjustable is connected to first resistance 11, and anode A ground connection, the negative electrode B of shunting a reference source 10 that three ends are adjustable is connected to second resistance 12, and negative electrode 12 is the output of the adjustable shunting a reference source 10 of three ends, first resistance 11 is connected with second resistance 12, and three ends are adjustable, and shunting a reference source reference edge C connects first resistance 11 and second resistance 12.
The utility model embodiment provides a kind of booster driving circuit, comprises from voltage stabilizing regulating circuit 1.Comprise the adjustable shunting a reference source 10 of three ends from voltage stabilizing regulating circuit 1, and according to the characteristic of the adjustable shunting a reference source of three ends 10 itself as can be known, has an a reference source Vref in the inside of the adjustable shunting a reference source 10 of three ends, the magnitude of voltage that is to say described reference edge C is Vref always, and anode A ground connection, and first resistance 11 is connected between reference edge C and the anode A, and therefore after adjustable shunting a reference source 10 work of three ends, the voltage at first resistance, 11 two ends is the voltage Vref of reference edge.Because negative electrode B is connected to second resistance 12, and reference edge C is connected to the lead that connects first resistance 11 and second resistance 12, so negative electrode B voltage is first resistance, 11 both end voltage and second resistance, 12 both end voltage sums.Because the voltage at first resistance, 11 two ends is fixed, therefore according to voltage divider principle, regulate the resistance R1 of first resistance 11 and the resistance R2 of second resistance 12 respectively, just can obtain the negative electrode B voltage of different value, negative electrode B is the output of the adjustable shunting a reference source 10 of three ends, so output voltage V out is negative electrode B voltage.Concrete analysis, output voltage V out=(1+R2/R1) Vref.After the resistance R2 of the resistance R1 of first resistance 11 and second resistance 12 determined, the magnitude of voltage of described output voltage had also just had exact value, and stablizes constant.From voltage stabilizing regulating loop 1 described output voltage is transferred to the enable pin of boost control chip, thereby can provide stable enable voltage, and can not make boost control chip the situation of misoperation occur for boost control chip.
Enable in the control circuit from voltage stabilizing above-mentioned, the voltage in DC input voitage source 23 is earlier by control switch circuit 2, enter then from voltage stabilizing regulating loop 1, wherein, the negative electrode B of shunting a reference source 10 that three ends are adjustable is the output from voltage stabilizing regulating loop 1, so negative electrode B is the whole output that enables control circuit from voltage stabilizing.To enable the output of control circuit from voltage stabilizing, promptly negative electrode B is connected to the enable pin 30 of boost control chip 3, and when negative electrode B had voltage output, described voltage just can transfer to the enable pin 30 of boost control chip 3.As the above analysis, describedly enable control circuit from voltage stabilizing and can export stable voltage, thereby enable pin 30 will obtain stable voltage, boost control chip 3 steady operations.
As shown in Figure 2, enabling control circuit from voltage stabilizing and also comprise control switch circuit 2 among the utility model embodiment, control switch circuit 2 comprises triode 21, the base stage D of triode 21 is connected to mainboard control switch 22, the collector electrode E of triode 21 is connected to the DC input voitage source 23 that enables control circuit from voltage stabilizing, and the emitter F of triode 21 is connected to negative electrode B.
In the present embodiment, triode 21 can be NPN type triode.
Triode 21 plays switch, because base stage D is connected to mainboard control switch 22, so can control according to the closed and disconnected of mainboard control switch 22 and voltage to be provided whether for base stage D, thereby determine whether the voltage transmission in DC input voitage source 23 to from voltage stabilizing regulating circuit 1.Mainboard control switch 22 can provide the mainboard working signal, and when mainboard control switch 22 closures, provide a high level voltage signal to base stage D, thereby make collector electrode E and emitter F conducting, and then triode 21 conductings.After triode 21 conductings, the DC input voitage that DC input voitage source 23 provides enters from voltage stabilizing regulating circuit 1.Wherein, in the backlight control circuit of LCD TV, this backlight control circuit can provide the voltage of 12V, and with the work of supply mainboard, the voltage of described 12V can also be simultaneously as the DC input voitage source 23 that enables control circuit from voltage stabilizing.In the present embodiment, what collector electrode E connected promptly is the 12V voltage source of backlight control circuit.When mainboard control switch 22 disconnects, do not have the voltage input on the base stage D, thereby triode 21 turn-offs, the DC input voitage that collector electrode E connects can not be transferred to from voltage stabilizing regulating circuit 1.
As shown in Figure 3, on the basis of above-mentioned control switch circuit 2, control switch circuit 2 can also comprise filter circuit 24, and filter circuit 24 comprises the 3rd resistance 241 and the electric capacity 242 that is connected in parallel, the 3rd resistance 241 that is connected in parallel and electric capacity 242 1 end ground connection, the other end is connected to base stage D.Because filter circuit 24 has an end to be connected to base stage D, and base stage D is connected to mainboard control switch 22, so being voltage signals that mainboard control switch 22 is provided, the effect of filter circuit 24 can provide galvanic current to press by filter circuit 24 to base stage D, in actual applications, when mainboard control switch 22 unexpected closures or other emergency case occur, might form peak voltage etc., can make described voltage signal stable level and smooth by filter circuit 24 this moment.Filter circuit 24 specifically constantly charges by electric capacity 242 and discharge process is finished filtering, and the positive pole of electric capacity 242 connects base stage D, minus earth.
It can also be seen that by Fig. 3, can be connected with first current-limiting resistance 31 between base stage D and the mainboard control switch 22, second current-limiting resistance 32 can be connected with between collector electrode E and the DC input voitage source 23, the 3rd current-limiting resistance 33 can be connected with between emitter F and the negative electrode B.It is not necessary that these three current-limiting resistances enable in the control circuit from voltage stabilizing at this, only plays metering function.Also just because of described current-limiting resistance has been a metering function, therefore the resistance value of described current-limiting resistance can not be very big, otherwise can divide to fall too much voltage, influences this enables control circuit from voltage stabilizing operate as normal.
In the utility model embodiment, describedly enable the adjustable shunting a reference source of three ends in the control circuit from voltage stabilizing to choose TL431 be that example describes.Described TL431 inside has a reference source of a 2.5V, that is to say that reference edge C has the constant voltage of 2.5V.About from the narration of voltage stabilizing regulating circuit 1 as can be known, first resistance 11 is connected between the reference edge C and anode A of described TL431 from above, anode A ground connection, and therefore after described TL431 worked, the voltage at first resistance, 11 two ends was the voltage 2.5V of reference edge C.The voltage of negative electrode B is first resistance, 11 both end voltage and second resistance, 12 both end voltage sums, and negative electrode B is the output of described TL431, according to voltage divider principle, and output voltage V out=Vref (1+R2/R1)=2.5 (1+R2/R1).For described TL431,2.5V＜Vout≤36V, promptly the output voltage of described TL431 can be exported any value in 2.5V to the 36V scope by the ratio of regulating first resistance 11 and second resistance 12.
Comprehensive above about control switch circuit 2 with from the analysis of voltage stabilizing regulating circuit 1, after mainboard control switch 22 closures, triode 21 conductings, the 12V DC input voitage that DC input voitage source 23 provides enter by described TL431, first resistance 11, second resistance 12, the 3rd current-limiting resistance 33 form from voltage stabilizing regulating circuit 1.After the DC input voitage of 12V imports, be carried in anode A, negative electrode B and the reference edge C of described TL431 by the biasing dividing potential drop of the 3rd current-limiting resistance 33, first resistance 11 and second resistance 12, a reference source regulating characteristics by described TL431 self loop that makes the voltage of negative electrode B of described TL431 form by first resistance 11 and second resistance 12 reaches balance then, thereby exports stable voltage.
In the utility model embodiment, the NCL30131-D that described boost control chip 3 is chosen in the NCL30131 series is that example describes.The effective range of the enable voltage of the enable pin 30 of NCL30131-D is between the 2.7V-3.4V, promptly has only when input on the enable pin 30 has voltage between the 2.7V-3.4V, and boost control chip 3 is normal steady operation.And the input voltage on the enable pin 30 promptly is the output voltage of negative electrode B, and described output voltage V out=(1+R2/R1) Vref=2.5 (1+R2/R1), for guaranteeing boost control chip NCL30131-D operate as normal, Vout should be between 2.7V-3.4V, the ratio R 2/R1 of resistance R1 by calculating the resistance R2 can get second resistance 12 and first resistance 11 should be between the 0.08-0.36, the resistance that for example can choose first resistance 11 and second resistance 12 is respectively 20K and 4.7K, this moment, R2/R1 was 0.235, described output voltage V out=2.5 (1+R2/R1)=3.09V, then should from voltage stabilizing enable the output voltage of control circuit can stable maintenance at 3.09V, satisfy the voltage request of the enable pin 30 of boost control chip NCL30131-D, can guarantee the boost control chip steady operation.
In addition, as shown in Figure 4, be connected with the 4th current-limiting resistance 34 between the described enable pin 30 that enables the output of control circuit and boost control chip 3 from voltage stabilizing.The same with above-mentioned first current-limiting resistance 31, second current-limiting resistance 32, the 3rd current-limiting resistance 33, the 4th current-limiting resistance 34 is not necessary in described booster driving circuit, only plays metering function, so the resistance value of the 4th current-limiting resistance 34 can not be very big.
Wherein, described booster driving circuit can be for driving the employed booster driving circuit of backlight in the liquid crystal display.At this moment, the 12V direct voltage that provides for backlight control circuit of the DC input voitage source 23 that connects of triode 21 collector electrode E.
The utility model embodiment also provides a kind of television set, comprise booster driving circuit, described booster driving circuit comprises and aforesaidly enables control circuit and boost control chip 3 from voltage stabilizing, and the described output that enables control circuit from voltage stabilizing is connected to the enable pin 30 of boost control chip 3.Referring to shown in Figure 1, enabling control circuit from voltage stabilizing described in the present embodiment comprises from voltage stabilizing regulating circuit 1, comprise the adjustable shunting a reference source 10 of three ends from voltage stabilizing regulating circuit 1, first resistance 11, second resistance 12, wherein, three ends are adjustable, and shunting a reference source 10 anode A are connected to first resistance 11, and anode A ground connection, three ends are adjustable, and shunting a reference source negative electrode B is connected to second resistance 12, and negative electrode 12 is the output of the adjustable shunting a reference source 10 of three ends, first resistance 11 is connected with second resistance 12, and three ends are adjustable, and shunting a reference source reference edge C connects first resistance 11 and second resistance 12.
The utility model embodiment provides a kind of television set, comprises from voltage stabilizing regulating circuit 1.Comprise the adjustable shunting a reference source 10 of three ends from voltage stabilizing regulating circuit 1, and according to the characteristic of the adjustable shunting a reference source of three ends 10 itself as can be known, has an a reference source Vref in the inside of the adjustable shunting a reference source 10 of three ends, the magnitude of voltage that is to say described reference edge C is Vref always, and anode A ground connection, and first resistance 11 is connected between reference edge C and the anode A, and therefore after adjustable shunting a reference source 10 work of three ends, the voltage at first resistance, 11 two ends is the voltage Vref of reference edge.Because negative electrode B is connected to second resistance 12, and reference edge C is connected to the lead that connects first resistance 11 and second resistance 12, so negative electrode B voltage is first resistance, 11 both end voltage and second resistance, 12 both end voltage sums.Because the voltage at first resistance, 11 two ends is fixed, therefore according to voltage divider principle, regulate the resistance R1 of first resistance 11 and the resistance R2 of second resistance 12 respectively, just can obtain the negative electrode B voltage of different value, negative electrode B is the output of the adjustable shunting a reference source 10 of three ends, so output voltage V out is negative electrode B voltage.Concrete analysis, output voltage V out=(1+R2/R1) Vref.After the resistance R2 of the resistance R1 of first resistance 11 and second resistance 12 determined, the magnitude of voltage of described output voltage had also just had exact value, and stablizes constant.From voltage stabilizing regulating loop 1 described output voltage is transferred to the enable pin of boost control chip, thereby can provide stable enable voltage, and can not make boost control chip the situation of misoperation occur for boost control chip.
Enable in the control circuit from voltage stabilizing above-mentioned, the voltage in DC input voitage source 23 is earlier by control switch circuit 2, enter then from voltage stabilizing regulating loop 1, wherein, the negative electrode B of shunting a reference source 10 that three ends are adjustable is the output from voltage stabilizing regulating loop 1, so negative electrode B is the whole output that enables control circuit from voltage stabilizing.To enable the output of control circuit from voltage stabilizing, promptly negative electrode B is connected to the enable pin 30 of boost control chip 3, and when negative electrode B had voltage output, described voltage just can transfer to the enable pin 30 of boost control chip 3.As the above analysis, describedly enable control circuit from voltage stabilizing and can export stable voltage, thereby enable pin 30 will obtain stable voltage, boost control chip 3 steady operations.
As shown in Figure 2, enabling control circuit from voltage stabilizing and also comprise control switch circuit 2 among the utility model embodiment, control switch circuit 2 comprises triode 21, triode 21 base stage D are connected to mainboard control switch 22, triode 21 collector electrode E are connected to the DC input voitage source 23 that enables control circuit from voltage stabilizing, and triode 21 emitter F are connected to negative electrode B.
In the present embodiment, triode 21 can be NPN type triode.
As shown in Figure 3, on the basis of above-mentioned control switch circuit 2, control switch circuit 2 can also comprise filter circuit 24, and filter circuit 24 comprises the 3rd resistance 241 and the electric capacity 242 that is connected in parallel, the 3rd resistance 241 that is connected in parallel and electric capacity 242 1 end ground connection, the other end is connected to base stage D.Because filter circuit 24 has an end to be connected to base stage D, and base stage D is connected to mainboard control switch 22, so being voltage signals that mainboard control switch 22 is provided, the effect of filter circuit 24 can provide galvanic current to press by filter circuit 24 to base stage D, in actual applications, when mainboard control switch 22 unexpected closures or other emergency case occur, might form peak voltage etc., can make described voltage signal stable level and smooth by filter circuit 24 this moment.Filter circuit 24 specifically constantly charges by electric capacity 242 and discharge process is finished filtering, and the positive pole of electric capacity 242 connects base stage D, minus earth.
It can also be seen that by Fig. 3, can be connected with first current-limiting resistance 31 between base stage D and the mainboard control switch 22, second current-limiting resistance 32 can be connected with between collector electrode E and the DC input voitage source 23, the 3rd current-limiting resistance 33 can be connected with between emitter F and the negative electrode B.It is not necessary that these three current-limiting resistances enable in the control circuit from voltage stabilizing at this, only plays metering function.Also just because of described current-limiting resistance has been a metering function, therefore the resistance value of described current-limiting resistance can not be very big, otherwise can divide to fall too much voltage, influences this enables control circuit from voltage stabilizing operate as normal.
In the utility model embodiment, describedly enable the adjustable shunting a reference source of three ends in the control circuit from voltage stabilizing to choose TL431 be that example describes.Described TL431 inside has a reference source of a 2.5V, that is to say that reference edge C has the constant voltage of 2.5V.About from the narration of voltage stabilizing regulating circuit 1 as can be known, first resistance 11 is connected between the reference edge C and anode A of described TL431 from above, anode A ground connection, and therefore after described TL431 worked, the voltage at first resistance, 11 two ends was the voltage 2.5V of reference edge C.The voltage of negative electrode B is first resistance, 11 both end voltage and second resistance, 12 both end voltage sums, and negative electrode B is the output of described TL431, according to voltage divider principle, and output voltage V out=Vref (1+R2/R1)=2.5 (1+R2/R1).For described TL431,2.5V＜Vout≤36V, promptly the output voltage of described TL431 can be exported any value in 2.5V to the 36V scope by the ratio of regulating first resistance 11 and second resistance 12.
Comprehensive above about control switch circuit 2 with from the analysis of voltage stabilizing regulating circuit 1, after mainboard control switch 22 closures, triode 21 conductings, the 12V DC input voitage that DC input voitage source 23 provides enter by described TL431, first resistance 11, second resistance 12, the 3rd current-limiting resistance 33 form from voltage stabilizing regulating circuit 1.After the DC input voitage of 12V imports, be carried in anode A, negative electrode B and the reference edge C of described TL431 by the biasing dividing potential drop of the 3rd current-limiting resistance 33, first resistance 11 and second resistance 12, a reference source regulating characteristics by described TL431 self loop that makes the voltage of negative electrode B of described TL431 form by first resistance 11 and second resistance 12 reaches balance then, thereby exports stable voltage.
In the utility model embodiment, the NCL30131-D that described boost control chip 3 is chosen in the NCL30131 series is that example describes.The effective range of the enable voltage of the enable pin 30 of NCL30131-D is between the 2.7V-3.4V, promptly has only when input on the enable pin 30 has voltage between the 2.7V-3.4V, and boost control chip 3 is normal steady operation.And the input voltage on the enable pin 30 promptly is the output voltage of negative electrode B, and described output voltage V out=(1+R2/R1) Vref=2.5 (1+R2/R1), for guaranteeing boost control chip NCL30131-D operate as normal, Vout should be between 2.7V-3.4V, the ratio R 2/R1 of resistance R1 by calculating the resistance R2 can get second resistance 12 and first resistance 11 should be between the 0.08-0.36, the resistance that for example can choose first resistance 11 and second resistance 12 is respectively 20K and 4.7K, this moment, R2/R1 was 0.235, described output voltage V out=2.5 (1+R2/R1)=3.09V, then should from voltage stabilizing enable the output voltage of control circuit can stable maintenance at 3.09V, satisfy the voltage request of the enable pin 30 of boost control chip NCL30131-D, can guarantee the boost control chip steady operation.
In addition, as shown in Figure 4, be connected with the 4th current-limiting resistance 34 between the described enable pin 30 that enables the output of control circuit and boost control chip 3 from voltage stabilizing.The same with above-mentioned first current-limiting resistance 31, second current-limiting resistance 32, the 3rd current-limiting resistance 33, the 4th current-limiting resistance 34 is not necessary in described booster driving circuit, only plays metering function, so the resistance value of the 4th current-limiting resistance 34 can not be very big.
Described television set comprises backlight, and described backlight connects described booster driving circuit.At this moment, the 12V direct voltage that provides for backlight control circuit of the DC input voitage source 23 that connects of triode 21 collector electrode E.Describedly enable control circuit from voltage stabilizing and provide stable voltage, guarantee that boost control chip 3 can steady operation, realize boost function, thereby provide needed voltage for backlight for the enable pin 30 of boost control chip 3.
The above; only be the specific embodiment of the present invention, but protection scope of the present invention is not limited thereto, anyly is familiar with those skilled in the art in the technical scope that the present invention discloses; can expect easily changing or replacing, all should be encompassed within protection scope of the present invention.Therefore, protection scope of the present invention should be as the criterion by described protection range with claim.
Claims (10)
1. one kind enables control circuit from voltage stabilizing, it is characterized in that, comprises from the voltage stabilizing regulating circuit, describedly comprises the adjustable shunting a reference source of three ends, first resistance, second resistance from the voltage stabilizing regulating circuit, wherein,
The adjustable shunting a reference source of described three ends anode is connected to described first resistance, and described plus earth, the adjustable shunting a reference source of described three ends negative electrode is connected to described second resistance, and described negative electrode is the output of the adjustable shunting a reference source of described three ends, described first resistance is connected with described second resistance, and the adjustable shunting a reference source of described three ends reference edge connects described first resistance and described second resistance.
2. according to claim 1ly enable control circuit from voltage stabilizing, it is characterized in that, also comprise the control switch circuit, described control switch circuit comprises triode, described transistor base is connected to the mainboard control switch, described transistor collector is connected to and describedly enables the DC input voitage source of control circuit from voltage stabilizing, and described transistor emitter is connected to described negative electrode.
3. according to claim 2ly enable control circuit from voltage stabilizing, it is characterized in that, described control switch circuit also comprises filter circuit, described filter circuit comprises the 3rd resistance and the electric capacity that is connected in parallel, described the 3rd resistance that is connected in parallel and electric capacity one end ground connection, the other end is connected to described base stage;
Be connected with first current-limiting resistance between described base stage and the described mainboard control switch; And/or
Be connected with second current-limiting resistance between described collector electrode and the described DC input voitage source.
4. describedly enable control circuit according to claim 2 or 3, it is characterized in that, be connected with the 3rd current-limiting resistance between described transistor emitter and the adjustable shunting a reference source of the described three ends negative electrode from voltage stabilizing.
5. describedly enable control circuit according to claim 2 or 3, it is characterized in that described triode is a NPN type triode from voltage stabilizing.
6. according to claim 1ly enable control circuit, it is characterized in that the pass between the output voltage of the adjustable shunting a reference source of described three ends and described first resistance and described second resistance is Vout=Vref (1+R2/R1) from voltage stabilizing.
7. booster driving circuit, it is characterized in that, comprise that each describedly enables control circuit and boost control chip from voltage stabilizing as claim 1-6, the described output that enables control circuit from voltage stabilizing is connected to the enable pin of described boost control chip, is connected with the 4th current-limiting resistance between the enable pin of described output and described boost control chip.
8. booster driving circuit according to claim 7 is characterized in that, described booster driving circuit is to drive the employed booster driving circuit of backlight in the liquid crystal display.
9. television set, it is characterized in that, comprise booster driving circuit, described booster driving circuit comprises that each describedly enables control circuit and boost control chip from voltage stabilizing as claim 1-6, and the described output that enables control circuit from voltage stabilizing is connected to the enable pin of described boost control chip.
10. television set according to claim 9 is characterized in that described television set comprises backlight, and described backlight connects described booster driving circuit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2011200652755U CN202035086U (en) | 2011-03-14 | 2011-03-14 | Self-voltage-stabilization enable control circuit, voltage boost drive circuit, and television set |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2011200652755U CN202035086U (en) | 2011-03-14 | 2011-03-14 | Self-voltage-stabilization enable control circuit, voltage boost drive circuit, and television set |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN202035086U true CN202035086U (en) | 2011-11-09 |
Family
ID=44897369
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2011200652755U Expired - Fee Related CN202035086U (en) | 2011-03-14 | 2011-03-14 | Self-voltage-stabilization enable control circuit, voltage boost drive circuit, and television set |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN202035086U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108429313A (en) * | 2018-03-28 | 2018-08-21 | 惠州市忠邦电子有限公司 | One kind is filled with being electrically integrated charger and its circuit |
| CN114217658A (en) * | 2021-11-03 | 2022-03-22 | 中冶南方（武汉）自动化有限公司 | Negative voltage reference circuit |
-
2011
- 2011-03-14 CN CN2011200652755U patent/CN202035086U/en not_active Expired - Fee Related
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108429313A (en) * | 2018-03-28 | 2018-08-21 | 惠州市忠邦电子有限公司 | One kind is filled with being electrically integrated charger and its circuit |
| CN108429313B (en) * | 2018-03-28 | 2024-01-12 | 惠州市忠邦电子有限公司 | Integrated power supply for charging and power consumption and circuit thereof |
| CN114217658A (en) * | 2021-11-03 | 2022-03-22 | 中冶南方（武汉）自动化有限公司 | Negative voltage reference circuit |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103529890B (en) | A kind of soft starting device and method | |
| CN201041734Y (en) | LCD power supply circuit and LCD | |
| CN104679087A (en) | Vehicle-mounted low-dropout linear voltage stabilizer circuit and low-voltage compensating circuit thereof | |
| CN103280765A (en) | Overvoltage protection circuit | |
| CN214755708U (en) | Dual-input power supply control circuit with constant voltage switching | |
| CN103079322B (en) | Closed loop light-emitting diode (LED) current control circuit and power-switching circuit | |
| CN203658888U (en) | USB power supply compensating circuit and portable electronic equipment | |
| CN202035086U (en) | Self-voltage-stabilization enable control circuit, voltage boost drive circuit, and television set | |
| CN203445774U (en) | Peak value current deviation generation circuit, peak value current sample hold circuit with compensation, constant current control circuit and switch power source | |
| CN101604909B (en) | Starting circuit for direct-current switch power supply | |
| CN203673378U (en) | Low-dropout direct-current stabilized power supply circuit | |
| CN106487073B (en) | Power supply circuit and electronic equipment | |
| CN205608580U (en) | Adjustable voltage stabilizing circuit of intelligence | |
| CN102214996B (en) | Micro-voltage-difference linear voltage-stabilizing power circuit | |
| CN202160107U (en) | Power switching circuit and power supply device of mobile terminal | |
| CN101763134A (en) | Parallel voltage stabilizing circuit | |
| CN107102191A (en) | The measuring method of a kind of electronic equipment load current | |
| CN101364797A (en) | Active voltage clamping grid driver circuit | |
| CN217282706U (en) | Dual-output sequential control circuit of switching power supply | |
| CN203326576U (en) | Switch power supply over-current protection circuit | |
| CN203233312U (en) | Switch power supply controller and switch power supply device | |
| CN2395306Y (en) | Power converter with constant current and constant voltage output | |
| CN205142005U (en) | Pwm voltage regulating circuit and constant voltage source circuit | |
| CN204119025U (en) | A kind of linear voltage dropping circuit for battery system | |
| CN103795400B (en) | High-precision sampling circuit based on VICOR module |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20111109 Termination date: 20190314 |
|
| CF01 | Termination of patent right due to non-payment of annual fee |