CN112116898B - Power supply circuit of backlight driving module - Google Patents
Power supply circuit of backlight driving module Download PDFInfo
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- CN112116898B CN112116898B CN201910543116.2A CN201910543116A CN112116898B CN 112116898 B CN112116898 B CN 112116898B CN 201910543116 A CN201910543116 A CN 201910543116A CN 112116898 B CN112116898 B CN 112116898B
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- G—PHYSICS
- G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
- G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
- G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
- G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
- G09G3/34—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source
- G09G3/3406—Control of illumination source
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- G—PHYSICS
- G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
- G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
- G09G2330/00—Aspects of power supply; Aspects of display protection and defect management
- G09G2330/02—Details of power systems and of start or stop of display operation
- G09G2330/021—Power management, e.g. power saving
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Abstract
The power supply circuit of the backlight driving module is used for supplying power to the backlight driving module and comprises an input voltage, a DCDC module, a comparator circuit, a reference power supply, a switching circuit and a feedback resistance module; the input end of the DCDC module is connected with the input voltage, and the output end of the DCDC module is connected with the feedback resistor module and is used for reducing the input voltage to output the power supply voltage; the comparison input end of the comparator circuit is connected with the input voltage, the reference input end is connected with the reference power supply, and the output end is connected with the switch circuit and is used for comparing the input voltage with the reference voltage and controlling the on-off of the switch circuit according to a comparison result; the switch circuit is connected with the feedback resistance module to adjust the feedback resistance value, and further realize automatic adjustment of output power supply voltage. The invention completely adopts hardware to realize automatic voltage adjustment, has simple and reliable circuit structure, is easy to realize, and can effectively reduce the overall power consumption of the HUD.
Description
Technical Field
The invention relates to a power supply circuit of a backlight driving module.
Background
Currently, integrated HUDs for passenger cars on the market generally adopt a TFT screen projection display scheme, and in order to accurately control the brightness of the HUD screen by using the duty ratio of PWM, a backlight power supply generally adopts a boost type backlight driving IC to drive a backlight LED lamp of the TFT screen.
In the power supply design, it is sometimes encountered that the allowable maximum input voltage of the backlight driving IC is smaller than the maximum operation voltage of the HUD, and therefore, the backlight power supply design of the HUD generally reduces the input voltage with DCDC and supplies power to the backlight driving IC. This power supply scheme has the following problems: the HUD complete machine is low in power conversion efficiency under the condition of rated voltage power supply for a long time. The reason is that: the HUD operating voltage range is required to be 9 to 16V in the vehicle factory, and in order to stably output DCDC in this operating voltage range, the output voltage needs to be set to 9V or less in consideration of DCDC EMI design. On one hand, the larger step-down amplitude of the DCDC reduces the power conversion efficiency; on the other hand, when the backlight driving IC circuit is always supplied with a voltage lower than 9V, the power supply conversion efficiency is not high due to the large step-up width.
Because the backlight drive IC circuit is the module with the largest power consumption of the whole machine, especially when the TFT screen works under the maximum brightness, the power consumption of the backlight drive IC circuit can even reach more than 80% of the power consumption of the whole machine, so the power conversion efficiency of the HUD is low due to the conventional power supply design scheme, and the power consumption of the whole machine cannot be reduced.
In order to improve the power conversion efficiency of the backlight driving IC, the difference between the output voltage and the input voltage of the backlight driving IC needs to be reduced on the premise of ensuring that DCDC stably works when 9-16V is supplied. Therefore, the design of the DCDC voltage reduction circuit with the output voltage automatically adjusted along with the input voltage supplies power for the backlight driving IC, and the design is significant for reducing the overall power consumption of the HUD.
Disclosure of Invention
The invention mainly aims to overcome the defects of low power conversion efficiency and large power consumption of the whole machine of a backlight driving IC in the prior art and provides a power supply circuit of a backlight driving module, wherein the output voltage of the power supply circuit is automatically adjusted along with the input voltage.
The invention adopts the following technical scheme:
a power supply circuit of a backlight driving module, which is used for supplying power to the backlight driving module, and is characterized in that: the device comprises an input voltage, a DCDC module, a comparator circuit, a reference power supply, a switching circuit and a feedback resistor module; the input end of the DCDC module is connected with the input voltage, and the output end of the DCDC module is connected with the feedback resistor module and is used for reducing the input voltage to output the power supply voltage; the comparison input end of the comparator circuit is connected with the input voltage, the reference input end is connected with the reference power supply, and the output end is connected with the switch circuit and is used for comparing the input voltage with the reference voltage and controlling the on-off of the switch circuit according to a comparison result; the switch circuit is connected with the feedback resistance module to adjust the feedback resistance value, and further realize automatic adjustment of output power supply voltage.
The circuit comprises a first comparator circuit, a second comparator circuit, a first switch circuit and a second switch circuit; the output end of the first comparator circuit is connected with the first switch circuit, and the output end of the second comparator circuit is connected with the second switch circuit; the feedback resistor module comprises a feedback resistor RfA and a feedback resistor RfB, one ends of the feedback resistor RfA and the feedback resistor RfB are respectively connected with the first switch circuit and the second switch, and the other ends are connected with the output end of the DCDC module and the ground side.
The first comparator circuit comprises a resistor R1, a capacitor C4, a resistor R2, a capacitor D3 and a comparator A1; one end of the resistor R1 is connected with the input voltage, and the other end of the resistor R1 is connected with the comparison input end of the comparator A1; one end of the capacitor C4, one end of the resistor R2 and the positive electrode of the capacitor D3 are connected with the comparison input end of the comparator A1, and the other end of the capacitor D3 is grounded.
The second comparator circuit comprises a resistor R3, a capacitor C6, a resistor R4, a capacitor D5 and a comparator A2; one end of the resistor R3 is connected with the input voltage, and the other end of the resistor R3 is connected with the comparison input end of the comparator A2; one end of the capacitor C6, one end of the resistor R4 and the positive electrode of the capacitor D5 are connected with the comparison input end of the comparator A2, and the other end of the capacitor D5 is grounded.
The first switching circuit comprises a resistor R5, a resistor R6, a capacitor C5, a diode D4 and a triode Q1; one end of the resistor R5 is connected with the output end of the first comparator circuit, and the other end of the resistor R5 is connected with the base electrode of the triode Q1; one end of the resistor R6, one end of the capacitor C5 and the negative electrode of the diode D4 are connected with the base electrode of the triode Q1, and the other end of the resistor is grounded; the collector of the triode Q1 is connected with a feedback resistor RfA, and the emitter is grounded.
The second switching circuit comprises a resistor R7, a resistor R8, a capacitor C7, a diode D6 and a triode Q2; one end of the resistor R7 is connected with the output end of the second comparator circuit, and the other end of the resistor R7 is connected with the base electrode of the triode Q2; one end of the resistor R8, one end of the capacitor C7 and the negative electrode of the diode D6 are connected with the base electrode of the triode Q2, and the other end of the resistor is grounded; the collector of the triode Q2 is connected with a feedback resistor RfB, and the emitter is grounded.
The feedback resistor module further comprises a feedback resistor Rf1 and a feedback resistor Rf2, wherein the feedback resistor Rf1 is connected to the output end of the DCDC module, and the feedback resistor Rf2 is connected to the grounding side of the output end of the DCDC module.
The reference power supply comprises a resistor R9 and a diode D7, one end of the resistor R9 is connected with the input voltage, the other end of the resistor R9 is connected with the cathode of the diode D7, and the anode of the diode D7 is grounded.
The diode D7 is a voltage stabilizing diode or a voltage stabilizing integrated circuit.
The DCDC module adopts a BUCK type DCDC module.
As can be seen from the above description of the present invention, compared with the prior art, the present invention has the following advantages:
the invention utilizes the voltage comparator to compare the reference level with the divided input voltage, adjusts the feedback resistance value of one side of the output end of the DCDC module to be grounded according to the comparison result of the comparator to realize the automatic adjustment function of the output voltage, reduces the value difference between the input voltage and the output voltage of the backlight drive IC circuit and improves the power conversion efficiency of the backlight drive IC circuit.
The invention completely adopts hardware to realize automatic voltage adjustment, has simple and reliable circuit structure, is easy to realize, and can effectively reduce the overall power consumption of the HUD.
Drawings
FIG. 1 is a schematic diagram of the present invention;
FIG. 2 is a circuit diagram of the present invention;
the invention is further described in detail below with reference to the drawings and the specific examples.
Detailed Description
The invention is further described below by means of specific embodiments.
Referring to fig. 1 and 2, a power supply circuit of a backlight driving module is used for supplying power to the backlight driving module, and the backlight driving module is used for providing constant current driving for backlight LEDs. The power supply circuit comprises an input voltage, a DCDC module, a comparator circuit, a reference power supply, a switching circuit, a feedback resistor module and the like.
The input end of the DCDC module is connected with the input voltage, and the output end of the DCDC module is connected with the feedback resistor module and is used for reducing the input voltage to output the power supply voltage. The DCDC module can adopt a BUCK type DCDC module. It can be provided with VIN, EN, SW, BOOT, FB, GND, etc. The VIN pin is connected with the input voltage VIN and is connected with a capacitor C1, the capacitor C2 is connected between the SW pin and the BOOT pin, and the EN pin is connected with the VIN pin. The SW pin is also connected with the cathode of a diode D2 and one end of an inductor L1, the anode of the diode D2 is grounded, and the other end of the inductor L1 outputs a supply voltage.
The feedback resistor module includes a feedback resistor RfA, a feedback resistor RfB, a feedback resistor Rf1 and a feedback resistor Rf2. The feedback resistor Rf1 is connected to the other end of the inductor L1 and the FB pin of the DCDC module, and the feedback resistor Rf2 is connected between the FB pin and the ground GND. Feedback resistor RfA and feedback resistor RfB are connected to the FB pin at one end. The resistance of the feedback resistor module influences the output power supply voltage value. The resistance of the feedback resistor module is not limited to this, and can be designed according to the needs.
The comparator circuit has a comparison input end connected with the input voltage, a reference input end connected with the reference power supply, and an output end connected with the switch circuit, and is used for comparing the divided input voltage with the reference voltage and controlling the on-off of the switch circuit according to the comparison result.
The number of the comparator circuits comprises a first comparator circuit and a second comparator circuit, which are arranged according to feedback resistance mathematics, and the number of the comparator circuits is not limited to the number. The first comparator circuit comprises a resistor R1, a capacitor C4, a resistor R2, a capacitor D3 and a comparator A1, wherein one end of the resistor R1 is connected with an input voltage, and the other end of the resistor R1 is connected with a comparison input end of the comparator A1. One end of the capacitor C4, one end of the resistor R2 and the positive electrode of the capacitor D3 are connected with the comparison input end of the comparator A1, and the other end of the capacitor D3 is grounded.
The second comparator circuit comprises a resistor R3, a capacitor C6, a resistor R4, a capacitor D5 and a comparator A2, wherein one end of the resistor R3 is connected with an input voltage, and the other end of the resistor R3 is connected with a comparison input end of the comparator A2. One end of the capacitor C6, one end of the resistor R4 and the positive electrode of the capacitor D5 are connected with the comparison input end of the comparator A2, and the other end of the capacitor D5 is grounded.
The reference power supply comprises a resistor R9 and a diode D7, wherein one end of the resistor R9 is connected with an input voltage VIN, the other end of the resistor R9 is connected with the cathode of the diode D7, and the anode of the diode D7 is grounded. The diode D7 is a zener diode or a zener integrated circuit, which may employ TL431.
The input end of the switch circuit is connected with the output end of the comparator circuit, and the output end of the switch circuit is connected with the feedback resistance module to adjust the feedback resistance value according to the comparison result, so that the automatic adjustment of the output power supply voltage is further realized. The circuit comprises a first switch circuit and a second switch circuit which are respectively connected with a first comparator circuit and a second comparator circuit in one-to-one correspondence. The number of switching circuits may be set according to the feedback resistance, not limited thereto.
The first switching circuit comprises a resistor R5, a resistor R6, a capacitor C5, a diode D4 and a triode Q1; one end of the resistor R5 is connected with the output end of the comparator A1, the other end of the resistor R5 is connected with the base electrode of the triode Q1, one end of the resistor R6, one end of the capacitor C5 and the negative electrode of the diode D4 are connected with the base electrode of the triode Q1, and the other end of the resistor R6 is grounded; the collector of the triode Q1 is connected with the other end of the feedback resistor RfA, and the emitter is grounded.
The second switching circuit comprises a resistor R7, a resistor R8, a capacitor C7, a diode D6 and a triode Q2; one end of the resistor R7 is connected with the output end of the comparator A2, the other end of the resistor R7 is connected with the base electrode of the triode Q2, one end of the resistor R8, one end of the capacitor C7 and the negative electrode of the diode D6 are connected with the base electrode of the triode Q2, and the other end of the resistor R8 is grounded; the collector of the triode Q2 is connected with the other end of the feedback resistor RfB, and the emitter is grounded.
In the switching circuit of the invention, other switching elements can be used to replace the triode. The working principle of the invention is as follows:
the input voltage VIN range of 9-16V is subdivided into three small ranges: 9-Va, va-Vb and Vb-16V, the DCDC module outputs different output voltages under different input voltage range conditions.
Assume that the parallel electrical value of the feedback resistor Rf2 and the feedback resistor RfA is Rf2'; the resistance value of Rf2, rfA and RfB in parallel is Rf2", and the following equation is given
Rf2’＝Rf2*RfA/(Rf2+RfA) (2-1)
Rf2”＝Rf2’*RfB/(Rf2’+RfB) (2-2)
Thus, there are several cases:
1) When 9 V.ltoreq.VIN < Va:
va=vin×r2/(r1+r2) < vref_tl431, comparator A1 outputs low level, Q1 is off;
vb=vin×r4/(r3+r4) < vref_tl431, comparator A2 outputs low level, Q2 is off;
therefore, rfA and RfB are in a high-impedance state to ground, the feedback resistance value of the output end of the DCDC module on the ground side is Rf2, and the output supply voltage is: vcc=vref (1+rf1/Rf 2).
2) When Va.ltoreq.VIN < Vb:
va=vin×r2/(r1+r2) > vref_tl431, and the comparator A1 outputs a high level, and Q1 is turned on;
vb=vin×r4/(r3+r4) < vref_tl431, comparator A2 outputs low level, Q2 is off;
therefore, the feedback resistance value at the output end of the DCDC module is Rf2 and the parallel power value Rf2' of RfA, and the output power supply voltage is: vcc=vref (1+rf1/Rf 2').
3) When Vb is less than or equal to VIN is less than or equal to 16V:
va=vin×r4/r3> Vref, the comparator A1 outputs a high level, Q1 is turned on;
vb=vin×r6/r5> Vref, the comparator A2 outputs a high level, Q2 is turned on;
therefore, the feedback resistance value of the output end of the DCDC module at the ground side is the resistance value of Rf2, rfA and RfB connected in parallel, and the output supply voltage is: vcc=vref (1+rf1/Rf 2 ").
In the invention, the values of the feedback resistor Rf2, the feedback resistor RfA and the feedback resistor RfB are calculated: assuming Vd is the lowest voltage difference between input and output when the DCDC module can stably output the maximum allowable output current, in order to make the backlight driving IC power achieve the ideal power conversion efficiency, the corresponding relationship between the output power supply voltage and the input voltage of the DCDC module is set as follows:
when VIN is 9V less than or equal to Va: vcc= (9-Vd) V
Va is less than or equal to VIN < Vb: vcc= (Va-Vd) V
Vb is less than or equal to VIN is less than or equal to 16V: vcc= (Vb-Vd) V
Therefore, the output voltage calculation formula of the DCDC module can be obtained
Vref*(1+Rf1/Rf2)＝(9-Vd)V (2-3)
Vref*(1+Rf1/Rf2’)＝(Va-Vd)V (2-5)
Vref*(1+Rf1/Rf2”)＝(Vb-Vd)V (2-6)
Under the condition determined by Rf1 and Vd, values of Rf2, rfA and RfB can be calculated from the formulas 2-1,2-2,2-3,2-4,2-5 and 2-6.
The invention calculates the values of the resistor R1, the resistor R2, the resistor R3 and the resistor R4
Since the voltage thresholds of the first comparator circuit and the second comparator circuit are Va and Vb, respectively, there are the following equations
Va*R2/(R1+R2)＝VREF_TL431 (2-7)
Vb*R4/(R3+R4)＝VREF_TL431 (2-8)
In the case where the values of the resistor R1 and the resistor R3 are determined, the values of R2 and R4 can be calculated from the formulas (2-7) and (2-8).
The value of the resistor R9 is calculated as follows:
the necessary condition for TL431 operation must be ensured when resistor R9 is selected, i.e. the current through the cathode is greater than 1mA. Since DCDC has the smallest current flowing through the cathode of TL431 when outputting (9-Vd) V, the current flowing through the cathode of TL431 at this time may be set to 2mA, so the value of R9 needs to satisfy the following condition:
(9－Vd－VREF_TL431)/R9＝2mA (2-9)
the invention utilizes the voltage comparator to compare the reference level with the divided input voltage, adjusts the feedback resistance value of one side of the output end of the DCDC module to be grounded according to the comparison result of the comparator to realize the automatic adjustment function of the output voltage, reduces the value difference between the input voltage and the output voltage of the backlight drive IC circuit and improves the power conversion efficiency of the backlight drive IC circuit.
The invention completely adopts hardware to realize automatic voltage adjustment, has simple and reliable circuit structure, is easy to realize, and can effectively reduce the overall power consumption of the HUD.
The foregoing is merely illustrative of specific embodiments of the present invention, but the design concept of the present invention is not limited thereto, and any insubstantial modification of the present invention by using the design concept shall fall within the scope of the present invention.
Claims (9)
1. A power supply circuit of a backlight driving module, which is used for supplying power to the backlight driving module, and is characterized in that: the device comprises an input voltage, a DCDC module, a comparator circuit, a reference power supply Vref, a switching circuit and a feedback resistor module; the input end of the DCDC module is connected with the input voltage, and the output end of the DCDC module is connected with the feedback resistor module and is used for reducing the input voltage to output the power supply voltage; the comparison input end of the comparator circuit is connected with the input voltage, the reference input end is connected with the reference power supply, and the output end is connected with the switch circuit and is used for comparing the input voltage with the reference voltage and controlling the on-off of the switch circuit according to a comparison result; the switch circuit is connected with the feedback resistance module to adjust the feedback resistance value, so as to further realize automatic adjustment of the output power supply voltage;
the circuit comprises a first comparator circuit, a second comparator circuit, a first switch circuit and a second switch circuit; the output end of the first comparator circuit is connected with the first switch circuit, and the output end of the second comparator circuit is connected with the second switch circuit; the feedback resistor module comprises a feedback resistor RfA and a feedback resistor RfB, one ends of the feedback resistor RfA and the feedback resistor RfB are respectively connected with the first switch circuit and the second switch circuit, and the other ends of the feedback resistor RfA and the feedback resistor RfB are connected with the output end of the DCDC module to the ground side;
the input voltage VIN range of 9-16V is subdivided into three small ranges: 9-Va, va-Vb and Vb-16V; assume that the parallel electrical value of the feedback resistor Rf2 and the feedback resistor RfA is Rf2'; the parallel resistance of Rf2, rfA and RfB is Rf2", the reference power is Vref, the input voltage is VIN, the following equation is given
Rf2’＝Rf2*RfA/(Rf2+RfA)
Rf2”＝Rf2’*RfB/(Rf2’+RfB)
Vd is the lowest voltage difference allowed by input and output when the DCDC module can stably output the maximum allowable output current, and in order to enable the backlight driving IC power supply to achieve ideal power supply conversion efficiency, the corresponding relation between the output power supply voltage and the input voltage of the DCDC module is set as follows:
when VIN is 9V less than or equal to Va: vcc= (9-Vd) V
Va is less than or equal to VIN < Vb: vcc= (Va-Vd) V
Vb is less than or equal to VIN is less than or equal to 16V: vcc= (Vb-Vd) V
Thus, there are several cases:
1) When 9 V.ltoreq.VIN < Va: rfA and RfB are in a high resistance state to the ground, the feedback resistance value of one side of the output end of the DCDC module is Rf2, and the output power supply voltage is: vcc=vref (1+rf1/Rf 2);
2) When Va.ltoreq.VIN < Vb: the feedback resistance value of the output end of the DCDC module at one side of the grounding is a parallel connection electric value Rf2' of Rf2 and RfA, and the output power supply voltage is as follows: vcc=vref (1+rf1/Rf 2');
3) When Vb is less than or equal to VIN is less than or equal to 16V, the feedback resistance value at one side of the output end of the DCDC module is the resistance value of Rf2, rfA and RfB which are connected in parallel, and the output power supply voltage is as follows: vcc=vref (1+rf1/Rf 2 ").
2. The power supply circuit of a backlight driving module as claimed in claim 1, wherein: the first comparator circuit comprises a resistor R1, a capacitor C4, a resistor R2, a capacitor D3 and a comparator A1; one end of the resistor R1 is connected with the input voltage, and the other end of the resistor R1 is connected with the comparison input end of the comparator A1; one end of the capacitor C4, one end of the resistor R2 and the positive electrode of the capacitor D3 are connected with the comparison input end of the comparator A1, and the other end of the capacitor D3 is grounded.
3. The power supply circuit of a backlight driving module as claimed in claim 1, wherein: the second comparator circuit comprises a resistor R3, a capacitor C6, a resistor R4, a capacitor D5 and a comparator A2; one end of the resistor R3 is connected with the input voltage, and the other end of the resistor R3 is connected with the comparison input end of the comparator A2; one end of the capacitor C6, one end of the resistor R4 and the positive electrode of the capacitor D5 are connected with the comparison input end of the comparator A2, and the other end of the capacitor D5 is grounded.
4. The power supply circuit of a backlight driving module as claimed in claim 1, wherein: the first switching circuit comprises a resistor R5, a resistor R6, a capacitor C5, a diode D4 and a triode Q1; one end of the resistor R5 is connected with the output end of the first comparator circuit, and the other end of the resistor R5 is connected with the base electrode of the triode Q1; one end of the resistor R6, one end of the capacitor C5 and the negative electrode of the diode D4 are connected with the base electrode of the triode Q1, and the other end of the resistor is grounded; the collector of the triode Q1 is connected with a feedback resistor RfA, and the emitter is grounded.
5. The power supply circuit of a backlight driving module as claimed in claim 1, wherein: the second switching circuit comprises a resistor R7, a resistor R8, a capacitor C7, a diode D6 and a triode Q2; one end of the resistor R7 is connected with the output end of the second comparator circuit, and the other end of the resistor R7 is connected with the base electrode of the triode Q2; one end of the resistor R8, one end of the capacitor C7 and the negative electrode of the diode D6 are connected with the base electrode of the triode Q2, and the other end of the resistor is grounded; the collector of the triode Q2 is connected with a feedback resistor RfB, and the emitter is grounded.
6. The power supply circuit of a backlight driving module as claimed in claim 1, wherein: the feedback resistor module further comprises a feedback resistor Rf1 and a feedback resistor Rf2, wherein the feedback resistor Rf1 is connected to the output end of the DCDC module, and the feedback resistor Rf2 is connected to the grounding side of the output end of the DCDC module.
7. The power supply circuit of a backlight driving module as claimed in claim 1, wherein: the reference power supply comprises a resistor R9 and a diode D7, one end of the resistor R9 is connected with the input voltage, the other end of the resistor R9 is connected with the cathode of the diode D7, and the anode of the diode D7 is grounded.
8. The power supply circuit of a backlight driving module as claimed in claim 7, wherein: the diode D7 is a voltage stabilizing diode or a voltage stabilizing integrated circuit.
9. The power supply circuit of a backlight driving module as claimed in claim 1, wherein: the DCDC module adopts a BUCK type DCDC module.
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| TW201445865A (en) * | 2013-05-21 | 2014-12-01 | Chao-Cheng Lu | Direct Current to Direct Circuit Converter |
| CN207518048U (en) * | 2017-11-29 | 2018-06-19 | 四川长虹电器股份有限公司 | A kind of laser diode drive segment light adjusting circuit |
| JP6978914B2 (en) * | 2017-12-05 | 2021-12-08 | シーシーエス株式会社 | Power supply unit and light irradiation system equipped with it |
| CN207559856U (en) * | 2017-12-07 | 2018-06-29 | 广州金升阳科技有限公司 | A kind of ON-OFF control circuit |
-
2019
- 2019-06-21 CN CN201910543116.2A patent/CN112116898B/en active Active
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| Publication number | Publication date |
|---|---|
| CN112116898A (en) | 2020-12-22 |
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