CN203942686U - A kind of circuit of adjusting supply voltage - Google Patents
A kind of circuit of adjusting supply voltage Download PDFInfo
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- CN203942686U CN203942686U CN201420357849.XU CN201420357849U CN203942686U CN 203942686 U CN203942686 U CN 203942686U CN 201420357849 U CN201420357849 U CN 201420357849U CN 203942686 U CN203942686 U CN 203942686U
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Abstract
The utility model discloses a kind of circuit of adjusting supply voltage, comprising: operational amplifier, photoelectrical coupler, error amplifier, the first resistance, divider resistance and feedback resistance; Wherein, described the first resistance is connected between voltage input end and the reverse input end of operational amplifier, and divider resistance is connected between voltage control signal end and operational amplifier reverse defeated; Error amplifier is connected between the reverse input end of operational amplifier and the output of operational amplifier; The input of photoelectrical coupler is connected with the output of described operational amplifier, and the output of photoelectrical coupler is connected with the output voltage control end of external power source chip; Feedback resistance is connected between voltage output end and the in-phase input end of operational amplifier.Adopt technical solutions of the utility model can accurately adjust the supply power voltage of LED color screen, improve ease of use.
Description
Technical field
The utility model relates to LED display power technique fields, relates in particular to a kind of circuit of adjusting supply voltage.
Background technology
Because LED color screen supply voltage difference is in the market very large, there are 5V, 4.2V, 3.8V, 3.3V etc., kind is more, gives to produce with stock and has caused very large puzzlement.Existing LED color screen includes: power unit, control section and LED screen display section.And in the time that different LED color screens requires different LED lamps to show, need manually the supply voltage of LED screen display section and control section manually to be adjusted, also need to test simultaneously, judge that whether this adjusting result is correct, easily occur regulating the situation of mistake or error in judgement.Prior art has not only increased workload, has also improved the probability of makeing mistakes.
Summary of the invention
Technical problem to be solved in the utility model is, a kind of circuit of adjusting supply voltage is provided, and can accurately adjust the supply power voltage of LED color screen, improves ease of use.
For solving above technical problem, the utility model embodiment provides a kind of circuit of adjusting supply voltage, comprising: operational amplifier, photoelectrical coupler, error amplifier, the first resistance, divider resistance and feedback resistance; Wherein, described the first resistance is connected between voltage input end and the reverse input end of operational amplifier, and divider resistance is connected between voltage control signal end and operational amplifier reverse defeated; Error amplifier is connected between the reverse input end of operational amplifier and the output of operational amplifier; The input of photoelectrical coupler is connected with the output of described operational amplifier, and the output of photoelectrical coupler is connected with the output voltage control end of external power source chip; Feedback resistance is connected between voltage output end and the in-phase input end of operational amplifier.
Further, described divider resistance comprises the second resistance and the 3rd resistance; Divider resistance is connected between voltage control signal end and the reverse input end of operational amplifier, be specially: described the second resistance is connected between the reverse input end and voltage control signal end of operational amplifier, and described the 3rd resistance is connected between the reverse input end and signal ground of operational amplifier.
Further, described feedback resistance comprises the 4th resistance and the 5th resistance; Described feedback resistance is connected between voltage output end and the in-phase input end of operational amplifier, be specially: described the 4th resistance is connected between voltage output end and the in-phase input end of operational amplifier, described the 5th resistance is connected between the in-phase input end and signal ground of described operational amplifier.
Further, described error amplifier comprises: the 6th resistance, the first electric capacity and the second electric capacity; Error amplifier is connected between the reverse input end of operational amplifier and the output of operational amplifier, is specially: described the 6th resistance connects between the reverse input end and the first electric capacity of described operational amplifier; Described the first electric capacity is connected between described the 6th resistance and the output of operational amplifier; Described the second electric capacity is connected between the reverse input end of operational amplifier and the output of operational amplifier.
Further, described photoelectrical coupler comprises: the 7th resistance, Light-Emitting Diode and optical signal converter; Wherein, described the 7th resistance is connected with light-emitting diode, and described light-emitting diode is connected with described optical signal converter; Described optical signal converter is connected with the output voltage control end of described external power source chip.
Therefore, the circuit of the adjustment supply voltage that the utility model embodiment provides, voltage control signal end is connected with operational amplifier, in the time of regulating power source voltage, the voltage of voltage control signal end changes, the output voltage of operational amplifier also changes thereupon, and the electric current that flows through photoelectrical coupler is changed.And the output of photoelectrical coupler is connected with the output voltage control end of external power source chip, output voltage is changed.At this moment voltage regulation resistance carries out dividing potential drop to output voltage, and operational amplifier generation negative feedback is regulated.In the time that circuit reaches stable state, the in-phase input end of operational amplifier and the voltage of reverse input end are almost equal, realize the adjustment of supply voltage.Adopt and manually adjust supply voltage than prior art, the technical solution of the utility model, by adjusting the voltage control signal of control module, can be adjusted the supply power voltage of LED display easily and accurately, meets the demand of the various LED color screens in market.
Brief description of the drawings
Fig. 1 is the structural representation of a kind of circuit of adjusting supply voltage that the utility model provides.
Embodiment
Below in conjunction with the accompanying drawing in the utility model embodiment, the technical scheme in the utility model embodiment is clearly and completely described.
Referring to Fig. 1, it is the structural representation of the circuit of the adjustment supply voltage that provides of the utility model.This circuit is arranged on the power module of LED color screen, is controlled by control circuit module, makes power module simultaneously to control circuit module and LED display power supply.
As shown in Figure 1, this main circuit will comprise: the first resistance R 1, divider resistance, operational amplifier U1B, feedback resistance, error amplifier and photoelectrical coupler.Wherein, the first resistance R 1 is connected between voltage input end VREF and the reverse input end 2 of operational amplifier U1B, and divider resistance is connected between voltage control signal end ADJ and the reverse input end 2 of operational amplifier U1B.Error amplifier is connected between the reverse input end 2 of operational amplifier U1B and the output 1 of operational amplifier U1B2.The input of photoelectrical coupler is connected with the output 1 of operational amplifier U1B, and the output 4 of photoelectrical coupler is connected with the output voltage control end V_Control of external power source chip.Feedback resistance is connected between voltage output end VOUT and the in-phase input end 3 of operational amplifier U1B.
In the present embodiment, divider resistance is made up of the second resistance R 2 and the 3rd resistance R 3.As shown in Figure 1, the second resistance R 2 is connected between the reverse input end 2 and voltage control signal end VREF of U1B, and the 3rd resistance R 3 is connected between the reverse input end 2 and signal ground of operational amplifier U1B.Divider resistance, in the time that the voltage of voltage control signal end ADJ changes, carries out dividing potential drop by input voltage, for operational amplifier U1B provides a constant voltage stabilizing benchmark.
In the present embodiment, feedback resistance is made up of the 4th resistance R 4 and the 5th resistance R 5.As shown in Figure 1, the 4th resistance R 4 is connected between voltage output end VOUT and the in-phase input end 3 of operational amplifier U1B, and the 5th resistance R 5 is connected between the in-phase input end 3 and signal ground of operational amplifier U1B.Feedback resistance, for output voltage is being carried out to dividing potential drop, feeds back to operational amplifier U1B output voltage and processes.
In the present embodiment, error amplifier is made up of the 6th resistance R 6, the first capacitor C 1 and the second capacitor C 2.As shown in Figure 1, between the reverse input end 2 and the first capacitor C 1 of the 6th resistance R 6 concatenation operation amplifier U1B.The first capacitor C 1 is connected between the 6th resistance R 6 and the output 1 of operational amplifier U1B.The second capacitor C 2 is connected between the reverse input end 2 of operational amplifier U1B and the output 1 of operational amplifier U1B.Error amplifier carries out Error Gain and phase compensation to this circuit, makes system works stable.
In the present embodiment, photoelectrical coupler is made up of the 7th resistance R 7, LED P 1A and optical signal converter P2B.As shown in Figure 1, the 7th resistance R 7 is connected with LED P 1A, and LED P 1A is connected with optical signal converter P1B.
In the present embodiment, the size of current of Light-Emitting Diode P1A is flow through in the impact of the size of the 7th resistance R 7.In the time flowing through the electric current of LED P 1A and increase, through photoelectricity transmission, the pin 4 voltage step-downs of optical signal converter P1B, because the output 4 of photoelectrical coupler and the out-put supply control end V_Control of external power source chip are connected.The lower voltage of out-put supply control end V_Control makes external power source chip reduce output voltage, and output voltage terminal is connected with feedback resistance of the present utility model, output voltage is carried out dividing potential drop by feedback resistance, again the output voltage after dividing potential drop is fed back to operational amplifier U1B, make the in-phase input end 3 of operational amplifier U1B and the voltage of reverse input end 2 almost equal, thereby make circuit reach stable state.
Operation principle of the present utility model is specific as follows: in the time there is no voltage control signal, the voltage of voltage control signal end ADJ is 0, and voltage input end VREF is to circuit input voltage, and voltage output end VOUT exports corresponding voltage.The voltage of voltage output end VOUT is determined by the voltage of voltage input end VREF completely.And when after the power supply normally of control module, control module is inputted corresponding voltage control signal, the magnitude of voltage of voltage control signal end ADJ changes.
If the magnitude of voltage of voltage control signal end ADJ raises, by the dividing potential drop effect of divider resistance R2 and R3, the voltage of the reverse input end 2 of operational amplifier U1B can be elevated, and the voltage of the output 1 of operational amplifier U1B can be reduced, and causes the electric current that flows through photoelectrical coupler to reduce.The electric current of photoelectrical coupler reduces to affect the out-put supply control end of external power source chip, and power supply chip control out-put supply raises.Output voltage is carried out dividing potential drop by feedback resistance, and the output voltage after dividing potential drop is fed back to operational amplifier U1B, makes the voltage of operational amplifier U1B in-phase input end 3 increase.When stable state, the in-phase input end 3 of operational amplifier U1B is almost equal with the voltage of reverse input end 2, reaches negative feedback regulatory function.
If the magnitude of voltage of voltage control signal end ADJ reduces, by the dividing potential drop effect of divider resistance R2 and R3, the voltage of the reverse input end 2 of operational amplifier U1B can be lowered, and the voltage of the output 1 of operational amplifier U1B can be raise, and causes the electric current that flows through photoelectrical coupler to increase.The circuit of photoelectrical coupler increases the out-put supply control end that can affect external power source chip, and power supply chip control out-put supply reduces.Output voltage is carried out dividing potential drop by feedback resistance, and the output voltage after dividing potential drop is fed back to operational amplifier U1B, make the lower voltage of operational amplifier U1B in-phase input end 3, when stable state, the in-phase input end 3 of operational amplifier U1B is almost equal with the voltage of reverse input end 2, reaches negative feedback regulatory function.
Therefore, the circuit of the adjustment supply voltage that the utility model embodiment provides, voltage control signal end is connected with operational amplifier, in the time of regulating power source voltage, the voltage of voltage control signal end changes, the output voltage of operational amplifier also changes thereupon, and the electric current that flows through photoelectrical coupler is changed.And the output of photoelectrical coupler is connected with the output voltage control end of external power source chip, output voltage is changed.At this moment voltage regulation resistance carries out dividing potential drop to output voltage, and operational amplifier generation negative feedback is regulated.In the time that circuit reaches stable state, the in-phase input end of operational amplifier and the voltage of reverse input end are almost equal, realize the adjustment of supply voltage.Adopt and manually adjust supply voltage than prior art, the technical solution of the utility model, by adjusting the magnitude of voltage of control module, can be adjusted the supply power voltage of LED display easily and accurately, meets the demand of market all kinds LED color screen.
The above is preferred implementation of the present utility model; it should be pointed out that for those skilled in the art, do not departing under the prerequisite of the utility model principle; can also make some improvements and modifications, these improvements and modifications are also considered as protection range of the present utility model.
Claims (5)
1. a circuit of adjusting supply voltage, is characterized in that, comprising: operational amplifier, photoelectrical coupler, error amplifier, the first resistance, divider resistance and feedback resistance;
Wherein, described the first resistance is connected between voltage input end and the reverse input end of operational amplifier, and divider resistance is connected between voltage control signal end and operational amplifier reverse defeated;
Error amplifier is connected between the reverse input end of operational amplifier and the output of operational amplifier;
The input of photoelectrical coupler is connected with the output of described operational amplifier, and the output of photoelectrical coupler is connected with the output voltage control end of external power source chip;
Feedback resistance is connected between voltage output end and the in-phase input end of operational amplifier.
2. the circuit of adjustment supply voltage according to claim 1, is characterized in that,
Described divider resistance comprises the second resistance and the 3rd resistance;
Divider resistance is connected between voltage control signal end and the reverse input end of operational amplifier, is specially:
Described the second resistance is connected between the reverse input end and voltage control signal end of operational amplifier, and described the 3rd resistance is connected between the reverse input end and signal ground of operational amplifier.
3. the circuit of adjustment supply voltage according to claim 1, is characterized in that,
Described feedback resistance comprises the 4th resistance and the 5th resistance;
Described feedback resistance is connected between voltage output end and the in-phase input end of operational amplifier, is specially:
Described the 4th resistance is connected between voltage output end and the in-phase input end of operational amplifier, and described the 5th resistance is connected between the in-phase input end and signal ground of described operational amplifier.
4. the circuit of adjustment supply voltage according to claim 1, is characterized in that,
Described error amplifier comprises: the 6th resistance, the first electric capacity and the second electric capacity;
Error amplifier is connected between the reverse input end of operational amplifier and the output of operational amplifier, is specially:
Described the 6th resistance connects between the reverse input end and the first electric capacity of described operational amplifier;
Described the first electric capacity is connected between described the 6th resistance and the output of operational amplifier;
Described the second electric capacity is connected between the reverse input end of operational amplifier and the output of operational amplifier.
5. the circuit of adjustment supply voltage according to claim 1, is characterized in that,
Described photoelectrical coupler comprises: the 7th resistance, Light-Emitting Diode and optical signal converter;
Wherein, described the 7th resistance is connected with light-emitting diode, and described light-emitting diode is connected with described optical signal converter;
Described optical signal converter is connected with the output voltage control end of described external power source chip.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420357849.XU CN203942686U (en) | 2014-06-30 | 2014-06-30 | A kind of circuit of adjusting supply voltage |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420357849.XU CN203942686U (en) | 2014-06-30 | 2014-06-30 | A kind of circuit of adjusting supply voltage |
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| Publication Number | Publication Date |
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| CN203942686U true CN203942686U (en) | 2014-11-12 |
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| CN201420357849.XU Active CN203942686U (en) | 2014-06-30 | 2014-06-30 | A kind of circuit of adjusting supply voltage |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105446407A (en) * | 2015-12-23 | 2016-03-30 | 深圳市中孚能电气设备有限公司 | Power supply circuit for electronic device |
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2014
- 2014-06-30 CN CN201420357849.XU patent/CN203942686U/en active Active
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105446407A (en) * | 2015-12-23 | 2016-03-30 | 深圳市中孚能电气设备有限公司 | Power supply circuit for electronic device |
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