CN220108262U - Input voltage regulating circuit and LED driving device - Google Patents
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Abstract
The utility model discloses an input voltage regulating circuit and an LED driving device, wherein the input voltage regulating circuit comprises: the reference voltage generation module is used for generating a reference voltage corresponding to a first preset value; the sampling module is used for sampling the input voltage of the LED driving device to obtain a sampling voltage; the comparison module is connected with the reference voltage generation module and the sampling module and outputs control voltage according to a comparison result of the reference voltage and the sampling voltage, wherein the LED driving device outputs driving voltage for driving the LED lamp group according to the control voltage, and the comparison module is configured to output the input voltage as the control voltage when the input voltage is smaller than a first preset value; when the input voltage is greater than or equal to the first preset value, the input voltage is regulated to be reduced by a second preset value as the control voltage. And the control voltage is regulated according to the comparison result of the input voltage and the first preset value, so that the damage of the LED lamp group caused by the overhigh input voltage when the load voltage requirement is lower is avoided.
Description
Technical Field
The utility model relates to the technical field of electronics, in particular to an input voltage regulating circuit and an LED driving device.
Background
The liquid crystal display device (Liquid Crystal Display, LCD) has many advantages such as thin body, power saving, no radiation, etc., and has been widely used. In an LCD display, the liquid crystal panel itself does not emit light, and the backlight module needs to provide a light source to display images normally, so the backlight module becomes one of the key components of the LCD device. In order to more conveniently control the brightness and color of the backlight, and obtain longer service life and lower energy consumption, modern LCD displays almost all adopt LED backlights.
The LED driving device generally controls the on/off of the LED backlight or adjusts the light emitting brightness thereof through a driving circuit. The driving circuit includes a boost chopper circuit, and in order to ensure the normal operation of the LED driving device, the output voltage of the driving circuit must be greater than the input voltage. In an ideal state, the voltage value of the input voltage of the driving circuit is fixed. However, in practical working conditions, the input voltage of the driving circuit may be affected by various factors (such as environmental factors) to generate a certain swing, and when the input voltage is high, for some backlight units with smaller voltage requirements, there are risks of backlight damage and potential safety hazards.
Disclosure of Invention
In view of the foregoing, an object of the present utility model is to provide an input voltage adjusting circuit and an LED driving device, which can prevent backlight damage caused by an excessively high input voltage by controlling the input voltage of the driving circuit.
According to an aspect of the present utility model, there is provided an input voltage adjusting circuit comprising: the reference voltage generation module is used for generating a reference voltage corresponding to a first preset value; the sampling module is used for sampling the input voltage of the LED driving device to obtain a sampling voltage; the comparison module is connected with the reference voltage generation module and the sampling module and outputs a control voltage according to a comparison result of the reference voltage and the sampling voltage, wherein the LED driving device outputs a driving voltage for driving the LED lamp group according to the control voltage, and the comparison module is configured to output the input voltage as the control voltage when the input voltage is smaller than the first preset value; and when the input voltage is greater than or equal to the first preset value, regulating the input voltage to reduce by a second preset value as the control voltage.
Optionally, the comparing module includes: the first comparison unit is respectively connected with the reference voltage generation module and the sampling module, and outputs a first voltage according to the reference voltage and the sampling voltage, and is configured to output the first voltage corresponding to the input voltage when the input voltage is smaller than the first preset value, output the first voltage as a negative voltage when the input voltage is larger than or equal to the first preset value, and the voltage value corresponds to the second preset value; the second comparison unit is respectively connected with the reference voltage generation module and the sampling module, outputs a second voltage according to the reference voltage and the sampling voltage, and is configured to output the second voltage to be zero when the input voltage is smaller than the first preset value and output the second voltage to correspond to the input voltage when the input voltage is larger than or equal to the first preset value; and a processing unit outputting the control voltage according to the first voltage and the second voltage.
Optionally, the reference voltage generating module includes a first resistor, a second resistor and a triode, wherein the first resistor is connected between a first power supply end and a base electrode of the triode, the triode and the second resistor are sequentially connected in series between the first power supply end and the ground, a collector electrode of the triode is connected with the first power supply end, an emitter electrode of the triode is connected with the second resistor, and a middle node of the triode and the second resistor outputs the reference voltage.
Optionally, the reference voltage generating module further includes a zener diode, wherein a cathode of the zener diode is connected to a base of the triode, and an anode of the zener diode is grounded.
Optionally, the sampling module includes a third resistor and a fourth resistor sequentially connected in series between the input end of the LED driving device and the ground, wherein an intermediate node of the third resistor and the fourth resistor outputs the sampling voltage.
Optionally, the first comparing unit includes a first comparator, the non-inverting input end of the first comparator inputs the reference voltage, the inverting input end inputs the sampling voltage, the positive power supply end inputs the input voltage, the negative power supply is connected with a second power supply end, the second power supply end provides a negative voltage, and the voltage value corresponds to the second preset value; the second comparison unit comprises a second comparator, the non-inverting input end of the second comparator inputs the sampling voltage, the inverting input end inputs the reference voltage, the positive power supply end inputs the input voltage, and the negative power supply is grounded.
Optionally, the first comparing unit further includes a fifth resistor and a sixth resistor, the reference voltage is input to the non-inverting input terminal of the first comparator through the fifth resistor, and the sampling voltage is input to the inverting input terminal of the first comparator through the sixth resistor; the second comparing unit further comprises a seventh resistor and an eighth resistor, the reference voltage is input into the inverting input end of the second comparator through the eighth resistor, the sampling voltage is input into the non-inverting input end of the second comparator through the seventh resistor, the resistance values of the fifth resistor and the eighth resistor are the same, and the resistance values of the sixth resistor and the seventh resistor are the same.
Optionally, the processing unit includes an in-phase adder, and the control voltage is a sum of the first voltage and the second voltage.
Optionally, the in-phase adder includes: an operational amplifier; a ninth resistor connected in series between the output of the first comparator and the non-inverting input of the operational amplifier; a tenth resistor connected in series between the output terminal of the second comparator and the non-inverting input terminal of the operational amplifier; an eleventh resistor and a twelfth resistor which are sequentially connected in series between the output end of the operational amplifier and the ground, and an intermediate node of the eleventh resistor and the twelfth resistor is connected with the inverting input end of the operational amplifier.
According to still another aspect of the present utility model, there is provided an LED driving apparatus comprising: an input voltage regulating circuit as claimed in any one of the preceding claims; and the driving circuit outputs driving voltage for driving the LED lamp group according to the control voltage.
According to the input voltage regulating circuit provided by the embodiment of the utility model, the input voltage Vctrl is provided for the driving circuit according to the comparison result of the input voltage of the LED driving device and the first preset value, specifically, when Vin is smaller than the first preset value, vin is taken as the input voltage of the driving circuit, and when Vin is larger than or equal to the first preset value, vin is reduced by a second preset value and then is input into the driving circuit. The LED lamp group is controlled by the input voltage adjusting circuit with a simple structure, so that the driving voltage of the LED lamp group exceeds the voltage requirement due to the fact that the input voltage of the LED driving device is high, the damage risk of the LED lamp group is reduced, and the potential safety hazard is eliminated.
Drawings
The above and other objects, features and advantages of the present utility model will become more apparent from the following description of embodiments of the present utility model with reference to the accompanying drawings, in which:
fig. 1 is a schematic diagram showing the structure of a conventional LED driving device;
FIG. 2 is a schematic diagram showing the structure of an LED driving device according to an embodiment of the present utility model;
FIG. 3 is a schematic diagram showing a circuit configuration of an input voltage adjusting circuit according to an embodiment of the present utility model;
fig. 4 shows a schematic graph of the present input voltage control effect.
Detailed Description
Various embodiments of the present utility model will be described in more detail below with reference to the accompanying drawings. The same reference numbers will be used throughout the drawings to refer to the same or like parts. For clarity, the various features of the drawings are not drawn to scale.
Certain terms are used throughout the description and claims to refer to particular components. It will be appreciated by those of ordinary skill in the art that manufacturers may refer to a component by different names. The present patent specification and claims do not take the form of an element or components as a functional element or components as a rule.
Meanwhile, it should be understood that in the following description, "circuit" refers to a conductive loop constituted by at least one element or sub-circuit through electrical connection or electromagnetic connection. When an element or circuit is referred to as being "connected to" another element or being "connected between" two nodes, it can be directly coupled or connected to the other element or intervening elements may be present and the connection between the elements may be physical, logical, or a combination thereof. In contrast, when an element is referred to as being "directly coupled to" or "directly connected to" another element, it means that there are no intervening elements present between the two.
Unless the context clearly requires otherwise, throughout the description and the claims, the words "comprise", "comprising", and the like are to be construed in an inclusive sense as opposed to an exclusive or exhaustive sense; that is, it is the meaning of "including but not limited to". Furthermore, the terms "first," "second," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. Furthermore, in the description of the present utility model, unless otherwise indicated, the meaning of "a plurality" is two or more.
Fig. 1 shows a schematic block diagram of a conventional LED driving apparatus. As shown in the drawing, the LED driving device 100 includes a driving circuit 110 and an LED lamp set 120, wherein the LED lamp set 120 is connected between an output end OUT and a feedback input end FB of the driving circuit 110, and the LED lamp set 120 includes a plurality of parallel branches, each of which includes at least one LED lamp bead 121 connected in series. The driving circuit 110 includes a step-up chopper circuit (not shown in the drawing) for stepping up the input voltage Vin to the output voltage Vout, thereby turning on or off the respective LED beads 121 or adjusting the luminance of the respective LED beads. In an ideal state, the input voltage Vin is maintained at a fixed voltage value (e.g., at 12V); in practical conditions, since the LED driving device is affected by external factors (e.g. under some high-temperature or low-temperature environmental conditions), the input voltage Vin may swing within a certain range (e.g. swing within a range of 5-21V). When the input voltage Vin swings to a higher voltage value, the driving circuit 110 outputs an output voltage Vout having a higher voltage value. For some LED lamp groups 120 with smaller voltage requirements (e.g., when the number of LED beads in series in a single leg is smaller), there is a risk of backlight damage and safety hazard. In order to avoid the above risks, in some working conditions, the voltage reduction circuit is used to reduce the voltage of Vin, however, the additional voltage reduction circuit increases the cost of the LED driving device, and in addition, the area of the LED driving device is increased, which is not beneficial to the development of high integration of the LED driving device.
Fig. 2 shows a schematic block diagram of an LED driving apparatus according to an embodiment of the present utility model. As shown in fig. 2, the LED driving device 200 includes an input voltage adjusting circuit 230 and a driving circuit 210 connected in sequence. The input end of the input voltage adjusting circuit 230 receives an input voltage Vin of the LED driving device 200, the output end of the input voltage adjusting circuit 230 is connected to the input end of the driving circuit 210, and the input voltage adjusting circuit 230 provides an input voltage Vctrl for the driving circuit according to a comparison result of Vin and a first preset value. The driving circuit 210 provides the driving voltage Vout to the LED lamp set 220 after boosting Vctrl to control on/off of the LED lamp set or adjust the brightness of the LED lamp set 220. It should be understood that any LED driving circuit in the prior art may be used for the driving circuit 210, and is not described and limited in the present utility model.
As shown in fig. 2, the input voltage adjusting circuit 230 includes a reference voltage generating module 231, a sampling module 232, and a comparing module 233 respectively connected to the reference voltage generating module 231 and the sampling module 232. Wherein, the reference voltage generating module 231 is configured to generate a reference voltage Vref corresponding to a first preset value; the sampling module 232 is configured to sample an input voltage Vin of the LED driving device to obtain a sampling voltage Vs; the comparison module 233 includes a first comparison unit 2331, a second comparison unit 2332, and a processing unit 2333. The first comparing unit 2331 is connected to the reference voltage generating module 231 and the sampling module 232, respectively, and outputs a first voltage V1 according to a comparison result of the reference voltage Vref and the sampling voltage Vs; the second comparing unit 2332 is connected to the reference voltage generating module 231 and the sampling module 232, respectively, and outputs a second voltage V2 according to a comparison result of the reference voltage Vref and the sampling voltage Vs; the processing unit 2333 is connected to the first comparing unit 2331 and the second comparing unit 2332, respectively, and outputs a control voltage Vctrl according to the first voltage V1 and the second voltage V2.
Further, fig. 3 shows a circuit diagram of an input voltage adjusting circuit according to an embodiment of the present utility model. As shown, the reference voltage generating module 231 includes a first resistor R1, a second resistor R2, and a transistor Q1. The triode Q1 is, for example, an NPN triode, the triode Q1 and the second resistor R2 are sequentially connected in series between a first power supply end (the power supply voltage is VCC) and ground, a collector of the triode Q1 is connected with the first power supply end, an emitter of the triode Q1 is connected with the second resistor R2, and an intermediate node of the triode Q1 and the second resistor R2 is used as an output end of the reference voltage generating module 231 to output the reference voltage Vref; the first resistor R1 is used as a driving resistor of the triode Q1, one end of the first resistor R1 is connected with the first power supply end, and the other end of the first resistor R1 is connected with the base electrode of the triode Q1. Further, in the preferred embodiment shown in fig. 3, the reference voltage generating module 231 further includes a zener diode D1 having an anode connected to ground and a cathode connected to the base of the transistor Q1. When the power supply voltage VCC of the first power supply end is not larger than the breakdown voltage of the zener diode D1, when the triode Q1 is in a conducting state, the voltage at two ends of the second resistor R2 is used as the reference voltage Vref, and when the power supply voltage VCC of the first power supply end swings to a higher potential under the influence of other factors to breakdown the zener diode, the reference voltage Vref follows the breakdown voltage of the zener diode D1, so that the influence of VCC swing on circuit accuracy is reduced.
As shown in fig. 3, the sampling module 232 includes a third resistor R3 and a fourth resistor R4 connected in series between the input terminal of the LED driving device and the ground, wherein an intermediate node of the third resistor R3 and the fourth resistor R4 outputs the sampling voltage Vs as an output terminal of the sampling module.
The first comparing branch 233 outputs a first voltage V1 according to the reference voltage Vref and the sampling voltage Vs. Specifically, referring to fig. 3, the first comparing branch 2331 includes a first comparator U2 and its pull-up resistor (resistor R13). The non-inverting input end of the first comparator U2 is connected with the intermediate node of the triode Q1 and the second resistor R2, and a reference voltage Vref is input; the inverting input end of the first comparator U2 is connected with the intermediate node of the third resistor R3 and the fourth resistor R4, and is used for inputting a sampling voltage Vs; the positive power supply end of the first comparator U2 is connected to the input voltage Vin of the LED driving device, and the negative power supply end is connected to the negative voltage-VEE with the voltage value being a second preset value. One end of the resistor R13 is connected with the input end of the LED driving device, and the other end of the resistor R is connected with the output end of the first comparator U2. The output end of the first comparator U2 outputs a first voltage V1, and when Vs is smaller than Vref, the first voltage V1 follows the positive power supply voltage Vin of the first comparator U2; when Vs is larger than or equal to Vref, the first voltage V1 follows the negative power supply voltage-VEE of the first comparator U2.
The second comparing branch 2332 outputs a second voltage V2 according to the reference voltage Vref and the sampling voltage Vs. Specifically, referring to fig. 3, the second comparing branch 2332 includes a second comparator U3 and its pull-up resistor (resistor R14). The non-inverting input end of the second comparator U3 is connected with the intermediate node of the third resistor R3 and the fourth resistor R4, and the sampling voltage Vs is input; the inverting input end of the first comparator U2 is connected with the intermediate node of the triode Q1 and the second resistor R2, and a reference voltage Vref is input; the positive power supply end of the second comparator U3 is connected to the input voltage Vin of the LED driving device, and the negative power supply end is grounded. One end of the resistor R14 is connected with the input end of the LED driving device, and the other end of the resistor R is connected with the output end of the second comparator U3. The output end of the second comparator U3 outputs a second voltage V2, and when Vs is smaller than Vref, V2 = 0V; when Vs is larger than or equal to Vref, V2 follows the positive power supply voltage Vin of the second comparator U3.
Further, in some embodiments, by adjusting the power supply voltage VCC of the first power supply terminal and the resistances of the third resistor R3 and the fourth resistor R4, the sampled voltage Vs < the reference voltage Vref when the input voltage Vin is smaller than the first preset value is satisfied; when the input voltage Vin is greater than or equal to a first preset value, the sampling voltage Vs is greater than or equal to the reference voltage Vref. In some other embodiments, since the supply voltage VCC of the first supply terminal and the third resistor R3 and the fourth resistor R4 are limited in type, it is more difficult to satisfy the above-mentioned magnitude relation, and therefore, the fifth resistor R5 is connected in series between the output terminal (the intermediate node of the triode and the second resistor R2) of the reference voltage generating module 231 and the non-inverting input terminal of the first comparator U2; an eighth resistor R8 is serially connected between the output end of the reference voltage generating module 231 and the inverting input end of the second comparator U3, so as to realize further adjustment of the reference voltage Vref, wherein the resistance values of the fifth resistor R5 and the eighth resistor R8 are the same. Likewise, the sixth resistor R6 may also be connected in series between the output terminal of the sampling module 232 (intermediate node of the third resistor R3 and the fourth resistor R4) and the inverting input terminal of the first comparator U2; a seventh resistor R7 is connected in series between the output end of the sampling module 232 and the non-inverting input end of the second comparator U3, so as to realize further adjustment of the sampling voltage Vs, wherein the resistance values of the sixth resistor R6 and the seventh resistor R7 are the same. The first and second comparing units 2331 and 2332 provide more accurate comparison results by adjusting the reference voltage Vref and/or the sampling voltage Vs.
The processing unit 2333 outputs the control voltage Vctrl by adding the first voltage V1 and the second voltage V2 using, for example, an in-phase adder circuit. As shown, processing unit 2333 includes an operational amplifier U1, resistors R9-R12. A resistor R9 (ninth resistor) is connected in series between the output terminal of the first comparing unit 2331 and the non-inverting input terminal of the operational amplifier U1; a resistor R10 (tenth resistor) is connected in series between the output terminal of the second comparing unit 2332 and the non-inverting input terminal of the operational amplifier U1; a resistor R11 (eleventh resistor) and a resistor R12 (twelfth resistor) are sequentially connected in series between the output terminal of the operational amplifier U1 and ground, and an intermediate node of the resistor R11 and the resistor R12 is connected to the inverting input terminal of the operational amplifier U1, and the output terminal of the operational amplifier U1 outputs the control voltage Vctrl. Further, the calculation formula of Vctrl is as follows:
according to the above formula (1), the resistances of the resistors R9 to R12 are adjusted so that vctrl=v1+v2 (e.g., the resistances of R9 to R12 are all 10kΩ).
In summary, the input voltage adjusting circuit 230 is configured to compare the input voltage of the LED driving device 200 with a first preset value according to the comparison result:
when the input voltage Vin is less than the first preset value, the sampling voltage Vs is less than the reference voltage Vref, v1=vin, v2=0, vctrl=v1+v2=vin;
when the input voltage Vin is greater than or equal to a first preset value, the sampling voltage Vs is greater than or equal to the reference voltage Vref, vin= -VEE, v2=vin, vctrl=v1+v2=vin-VEE.
Fig. 4 shows a relationship between an input voltage Vin and an output voltage Vctrl of the input voltage regulator circuit according to an embodiment of the present utility model. The input voltage Vin of the LED driving device 200 swings between 5V and 21V, and takes the first preset value as 18V and the second preset value as 2V as an example. As shown, vctrl=vin when Vin < 18V; when Vin is greater than or equal to 18V, vctrl=Vin-2.
According to the input voltage regulating circuit provided by the embodiment of the utility model, the input voltage Vctrl is provided for the driving circuit according to the comparison result of the input voltage of the LED driving device and the first preset value, specifically, when Vin is smaller than the first preset value, vin is taken as the input voltage of the driving circuit, and when Vin is larger than or equal to the first preset value, vin is reduced by a second preset value and then is input into the driving circuit. The LED lamp group is controlled by the input voltage adjusting circuit with a simple structure, so that the driving voltage of the LED lamp group exceeds the voltage requirement due to the fact that the input voltage of the LED driving device is high, the damage risk of the LED lamp group is reduced, and the potential safety hazard is eliminated.
Embodiments in accordance with the present utility model, as described above, are not intended to be exhaustive or to limit the utility model to the precise embodiments disclosed. Obviously, many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the utility model and the practical application, to thereby enable others skilled in the art to best utilize the utility model and various modifications as are suited to the particular use contemplated. The scope of the utility model should be determined by the following claims.
Claims (10)
1. An input voltage regulation circuit, comprising:
the reference voltage generation module is used for generating a reference voltage corresponding to a first preset value;
the sampling module is used for sampling the input voltage of the LED driving device to obtain a sampling voltage; and
the comparison module is connected with the reference voltage generation module and the sampling module and outputs control voltage according to the comparison result of the reference voltage and the sampling voltage,
wherein the LED driving device outputs a driving voltage for driving the LED lamp group according to the control voltage, and the comparison module is configured to output the input voltage as the control voltage when the input voltage is smaller than the first preset value; and when the input voltage is greater than or equal to the first preset value, regulating the input voltage to reduce by a second preset value as the control voltage.
2. The input voltage regulation circuit of claim 1, wherein the comparison module comprises:
the first comparison unit is respectively connected with the reference voltage generation module and the sampling module, and outputs a first voltage according to the reference voltage and the sampling voltage, and is configured to output the first voltage corresponding to the input voltage when the input voltage is smaller than the first preset value, output the first voltage as a negative voltage when the input voltage is larger than or equal to the first preset value, and the voltage value corresponds to the second preset value;
the second comparison unit is respectively connected with the reference voltage generation module and the sampling module, outputs a second voltage according to the reference voltage and the sampling voltage, and is configured to output the second voltage to be zero when the input voltage is smaller than the first preset value and output the second voltage to correspond to the input voltage when the input voltage is larger than or equal to the first preset value; and
and the processing unit outputs the control voltage according to the first voltage and the second voltage.
3. The input voltage regulating circuit of claim 2, wherein the reference voltage generating module comprises a first resistor, a second resistor and a triode, wherein the first resistor is connected between a first power supply terminal and a base electrode of the triode, the triode and the second resistor are sequentially connected in series between the first power supply terminal and the ground, a collector electrode of the triode is connected with the first power supply terminal, an emitter electrode of the triode is connected with the second resistor, and an intermediate node of the triode and the second resistor outputs the reference voltage.
4. The input voltage regulation circuit of claim 3 wherein the reference voltage generation module further comprises a zener diode having a cathode coupled to the base of the transistor and an anode coupled to ground.
5. The input voltage regulating circuit of claim 2, wherein the sampling module comprises a third resistor and a fourth resistor connected in series in sequence between the LED driver input and ground, wherein an intermediate node of the third resistor and the fourth resistor outputs the sampled voltage.
6. The input voltage regulating circuit of claim 2, wherein the input voltage regulating circuit comprises,
the first comparison unit comprises a first comparator, wherein the non-inverting input end of the first comparator inputs the reference voltage, the inverting input end inputs the sampling voltage, the positive power supply end inputs the input voltage, the negative power supply is connected with a second power supply end, the second power supply end provides negative voltage, and the voltage value corresponds to the second preset value;
the second comparison unit comprises a second comparator, the non-inverting input end of the second comparator inputs the sampling voltage, the inverting input end inputs the reference voltage, the positive power supply end inputs the input voltage, and the negative power supply is grounded.
7. The input voltage regulating circuit of claim 6, wherein the input voltage regulator circuit comprises,
the first comparison unit further comprises a fifth resistor and a sixth resistor, the reference voltage is input into the non-inverting input end of the first comparator through the fifth resistor, and the sampling voltage is input into the inverting input end of the first comparator through the sixth resistor;
the second comparing unit further comprises a seventh resistor and an eighth resistor, the reference voltage is input to the inverting input terminal of the second comparator through the eighth resistor, the sampling voltage is input to the non-inverting input terminal of the second comparator through the seventh resistor,
and the fifth resistor and the eighth resistor have the same resistance, and the sixth resistor and the seventh resistor have the same resistance.
8. The input voltage regulation circuit of claim 6 wherein the processing unit includes an in-phase adder, the control voltage being a sum of the first voltage and the second voltage.
9. The input voltage regulation circuit of claim 8 wherein the in-phase adder comprises:
an operational amplifier;
a ninth resistor connected in series between the output of the first comparator and the non-inverting input of the operational amplifier;
a tenth resistor connected in series between the output terminal of the second comparator and the non-inverting input terminal of the operational amplifier;
an eleventh resistor and a twelfth resistor which are sequentially connected in series between the output end of the operational amplifier and the ground, and an intermediate node of the eleventh resistor and the twelfth resistor is connected with the inverting input end of the operational amplifier.
10. An LED driving device, comprising:
the input voltage regulating circuit of any one of claims 1 to 9;
and the driving circuit outputs driving voltage for driving the LED lamp group according to the control voltage.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202321618640.XU CN220108262U (en) | 2023-06-25 | 2023-06-25 | Input voltage regulating circuit and LED driving device |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202321618640.XU CN220108262U (en) | 2023-06-25 | 2023-06-25 | Input voltage regulating circuit and LED driving device |
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| CN220108262U true CN220108262U (en) | 2023-11-28 |
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| GR01 | Patent grant | ||
| GR01 | Patent grant |