Dynamic voltage output circuit and power consumption reduction system

Abstract

The utility model discloses a dynamic voltage output circuit and a power consumption reduction system, and the circuit comprises a controller which is used for providing a control signal; the digital-to-analog converter is connected with the output end of the controller and is used for converting the control signal into a voltage signal; the voltage-to-constant current circuit is connected with the output end of the digital-to-analog converter and is used for converting the voltage signal into a current signal; the load is connected with the output end of the voltage-to-constant current circuit; the constant voltage-to-constant current circuit is connected with the load and is used for acquiring the output voltage of the load; and the Buck circuit is respectively connected with the constant voltage-to-constant current circuit and the voltage-to-constant current circuit, and is used for adjusting the control voltage output to the voltage-to-constant current circuit according to the output voltage of the load acquired by the constant voltage-to-constant current circuit. Through the circuit, the power consumption in the voltage-to-constant current circuit under a small load is reduced.

Description

TECHNICAL FIELD

[0001] The utility model relates to circuit technical field especially is related to dynamic voltage output circuit and reduce power consumption system. BACKGROUND

[0002] At present, the analog output (AO) circuit used to control the conduction degree of the regulating valve in industry is generally divided into two types, namely current output type AO circuit and voltage output type AO circuit. However, the current output type AO circuit is usually adopted most of the time, which includes a micro controller unit (MCU), a digital-to-analog converter (DAC) and a voltage-to-current conversion circuit (V / I conversion circuit).

[0003] The existing V / I conversion circuit adopts constant voltage power supply, which means that the power consumption of the entire system is a constant value under the condition that the output current is unchanged. Therefore, when the external load is very small, the power consumption generated at the load is also very small, which further leads to a large power consumption of the V / I conversion circuit.

[0004] In view of the above problems, how to reduce the power consumption of the V / I conversion circuit under small load conditions is a problem that the person skilled in the art strives to solve. SUMMARY

[0005] The present application provides a dynamic voltage output circuit and a power consumption reduction system, which is beneficial to reduce the power consumption of the V / I conversion circuit under small load conditions and avoid causing system heating.

[0006] In a first aspect, the present application provides a dynamic voltage output circuit, wherein the dynamic voltage output circuit comprises: a controller configured to provide a control signal; a digital-to-analog converter connected to an output terminal of the controller and configured to convert the control signal into a voltage signal; a voltage-to-constant current circuit connected to an output terminal of the digital-to-analog converter and configured to convert the voltage signal into a current signal; a load connected to an output terminal of the voltage-to-constant current circuit; a constant voltage-to-constant current circuit connected to the load and configured to collect an output voltage of the load; and a Buck circuit connected to the constant voltage-to-constant current circuit and the voltage-to-constant current circuit, respectively, and configured to adjust a control voltage output to the voltage-to-constant current circuit according to the output voltage of the load collected by the constant voltage-to-constant current circuit.

[0007] The control voltage is proportional to the output voltage of the load.

[0008] The voltage-to-constant current circuit comprises at least a current expansion triode, a first amplifier and a feedback resistor; a base of the current expansion triode is connected with an output end of the first amplifier, a collector of the current expansion triode is connected with an output end of the Buck circuit, an emitter of the current expansion triode is connected with the load through the feedback resistor, and a control voltage output by the Buck circuit adjusts a voltage difference between the collector and the emitter of the current expansion triode.

[0009] The current expansion triode is an NPN triode.

[0010] The voltage-to-constant current circuit further comprises a second amplifier, a first resistor, a second resistor, a third resistor, a fourth resistor and a fifth resistor; a positive input end of the first amplifier is connected with an output end of the digital-to-analog converter through the first resistor and connected with an output end of the second amplifier through the second resistor; a negative input end of the first amplifier is connected with the third resistor and connected with the feedback resistor and the emitter of the current expansion triode through the fourth resistor, and an output end of the first amplifier is connected with the base of the current expansion triode through the fifth resistor; wherein a positive input end of the second amplifier is connected with the load, and a negative input end of the second amplifier is connected with the output end of the second amplifier.

[0011] The resistance values of the first resistor and the second resistor are the same, and the resistance values of the third resistor and the fourth resistor are the same; a current signal I output by the voltage-to-constant current circuit is (VIN / R6)×(Rt2 / Rt1); wherein VIN is a voltage signal received by the voltage-to-constant current circuit, R6 is a resistance value of the feedback resistor, Rt1 is a resistance value of the first resistor or the second resistor, and Rt2 is a resistance value of the third resistor or the fourth resistor.

[0012] The constant voltage-to-constant current circuit comprises a compensation triode and a third amplifier; a positive input end of the third amplifier is connected with an output end of the voltage-to-constant current circuit and the load, a negative input end of the third amplifier is connected with an emitter of the compensation triode, and an output end of the third amplifier is connected with a base of the compensation triode; a collector of the compensation triode is connected with an input end of the Buck circuit.

[0013] The constant voltage-to-constant current circuit further comprises a seventh resistor, an eighth resistor, a ninth resistor and a tenth resistor; the base of the compensation triode is further connected with the seventh resistor and the eighth resistor respectively; the emitter of the compensation triode is connected with the ninth resistor, and the collector of the compensation triode is connected with the tenth resistor; wherein a control voltage is related to a ratio of the ninth resistor and the tenth resistor.

[0014] The constant-voltage-to-constant-current circuit further comprises a compensation diode, a positive electrode of the compensation diode is connected to an output terminal of the third amplifier, and a negative electrode of the compensation diode is connected to a base of the compensation triode.

[0015] The compensation triode is a PNP type triode.

[0016] In a second aspect, the application provides a power consumption reduction system, wherein the power consumption reduction system comprises the dynamic voltage output circuit according to any one of the first aspect.

[0017] The application has the beneficial effect that the voltage value on the load is collected through the constant-voltage-to-constant-current circuit, and then the control voltage output to the constant-voltage-to-constant-current circuit is adjusted according to the collected voltage value through the Buck circuit, so as to reduce the loss of the voltage signal in the constant-voltage-to-constant-current circuit, and solve the problem of serious heating of the power supply system when the load is small. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the application, the following will briefly introduce the drawings needed to be used in the embodiment description. Obviously, the drawings in the following description are only some embodiments of the application, and for those skilled in the art, other drawings can also be obtained without creative labor.

[0019] Figure 1 The structural schematic diagram of the dynamic voltage output circuit according to an embodiment of the application is shown in the figure.

[0020] Figure 2 The circuit structural schematic diagram of a specific embodiment of the dynamic voltage output circuit according to the application is shown in the figure. DETAILED DESCRIPTION

[0021] The technical solutions in the embodiments of the application will be described clearly and completely in the following with reference to the drawings of the embodiments of the application. Obviously, the described embodiments are only some embodiments of the application, not all embodiments. Based on the embodiments of the application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the application.

[0022] The terms used in the embodiments of the application are only for the purpose of describing specific embodiments, and are not intended to limit the application. The terms "first", "second", and the like in the specification and claims of the application and the above-mentioned drawings are used to distinguish similar objects, and do not necessarily describe a specific order or sequence.

[0023] It should be understood that the terms "comprise", "comprising", or any other variation thereof, used in the present document are intended to encompass non-exclusive inclusions, such that processes, methods, articles, or apparatuses that comprise a list of elements are not limited to those elements, but can include other elements not expressly listed or inherent to such processes, methods, articles, or apparatuses. Without further limitation, an element defined by an "comprising" statement is not excluded from a process, method, article, or apparatus that includes the element, even though the same process, method, article, or apparatus can also include other identical elements.

[0024] Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment can be included in at least one embodiment of the application. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are they necessarily mutually exclusive of one another. It is expressly understood that the embodiments described herein can be combined with each other in their various permutations and combinations.

[0025] The application provides a dynamic voltage output circuit, please refer to Figure 1 , Figure 1 The application provides a dynamic voltage output circuit, please refer to Figure 1 The dynamic voltage output circuit includes a controller 11, a digital-to-analog converter 12, a voltage-to-current converter 13, a load 14, a constant voltage-to-current converter 15, and a Buck circuit 16.

[0026] The controller (MUC) 11 is configured to provide a control signal to the circuit.

[0027] The digital-to-analog converter (DAC) 12 is connected to the output terminal of the controller 11, and is configured to convert the control signal output by the controller 11 into a voltage signal and output the voltage signal to the voltage-to-current converter 13.

[0028] The voltage-to-current converter 13, also referred to as a V / I conversion circuit, is connected to the output terminal of the digital-to-analog converter 12, and is configured to convert the received voltage signal into a current signal and output the current signal to the load 14.

[0029] The constant voltage-to-current converter 15, also referred to as a follower circuit, is connected to the load 14, and is configured to collect an output voltage Vfb on the load 14. The output voltage Vfb is the voltage output by the dynamic voltage output circuit to the load 14.

[0030] The Buck circuit 16 is connected with the constant-voltage-to-constant-current circuit 15 and the voltage-to-constant-current circuit 13 respectively, and is used for adjusting the control voltage POWER output to the voltage-to-constant-current circuit 13 according to the output voltage Vfb of the load 14 collected by the constant-voltage-to-constant-current circuit 15. The Buck circuit 16 includes an input end and an output end. Specifically, the input end of the Buck circuit 16 is connected with the constant-voltage-to-constant-current circuit 15, and the output end is connected with the voltage-to-constant-current circuit 13, and is used for adjusting the control voltage POWER input to the voltage-to-constant-current circuit 13 according to the size of the load, so as to reduce the loss in the voltage-to-constant-current circuit 13. The control voltage is proportional to the output voltage of the load. Specifically, the control voltage POWER is a dynamic voltage, and the size of the control voltage POWER output depends on the size of the load. When the load is small, the voltage on the load is detected to be small, and the control voltage POWER outputs a small voltage.

[0031] In the conventional voltage-to-constant-current circuit, since the value of the supply voltage is fixed, the power consumption of the entire circuit is also fixed according to the formula P=UI. When the line impedance and the regulating valve load connected in the circuit are small, the power consumption on the line impedance and the regulating valve load is also small. At this time, the V / I conversion circuit will generate a large power consumption, which will cause the V / I conversion circuit to generate a large heat and damage the circuit.

[0032] In the embodiment, the constant-voltage-to-constant-current circuit 15 and the Buck circuit 16 control the voltage input to the load to change with the size of the load, so that when the load is small, the supply voltage input to the voltage-to-constant-current circuit is also small, thereby reducing the power consumption.

[0033] In some embodiments, please further refer to Figure 2 , Figure 2 The circuit structure schematic diagram of a specific embodiment of the dynamic voltage output circuit provided in the present application is shown in the following figure.

[0034] The load 14 includes a load resistor RL2.

[0035] In some embodiments, the voltage-to-constant-current circuit 13 includes a current expansion transistor Q1, a first amplifier U1A and a feedback resistor R6. The base of the current expansion transistor Q1 is connected with the output end of the first amplifier U1A. The current expansion transistor Q1 is used for improving the output capacity of the first amplifier U1A. The collector of the current expansion transistor Q1 is connected with the output end of the Buck circuit 16, and the emitter of the current expansion transistor Q1 is connected with the load resistor RL2 through the feedback resistor R6. The control voltage POWER output by the Buck circuit 16 adjusts the voltage difference between the collector and the emitter of the current expansion transistor Q1, so as to reduce the power loss in the voltage-to-constant-current circuit 13. The feedback resistor R6 can adjust the size of the current output to the load resistor RL2.

[0036] In some embodiments, the voltage-to-current circuit 13 further comprises a second amplifier U1B, a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, and a fifth resistor R5.

[0037] In some embodiments, the positive input terminal of the first amplifier U1A is connected to the output terminal VIN of the digital-to-analog converter through the first resistor R1, and connected to the output terminal of the second amplifier U1B through the second resistor R2. The negative input terminal of the first amplifier U1A is connected to the third resistor R3, and connected to the feedback resistor R6 and the emitter of the current expansion transistor Q1 through the fourth resistor R4. The output terminal of the first amplifier U1A is connected to the base of the current expansion transistor Q1 through the fifth resistor R5.

[0038] In some embodiments, the positive input terminal of the second amplifier U1B is connected to the load resistor RL2, and the negative input terminal of the second amplifier U1B is connected to the output terminal of the second amplifier U1B, forming a feedback circuit for adjusting the output of the first amplifier U1B according to the size of the load, and further adjusting the base of the current expansion transistor Q1.

[0039] The principle of adjusting the output current by the feedback resistor R6 is as follows:

[0040] The first resistor R1 and the second resistor R2 have the same resistance value, and the third resistor R3 and the fourth resistor R4 have the same resistance value. Assuming that the first resistor R1 is equal to the second resistor R2, and equal to Rt1, and the third resistor R3 is equal to the fourth resistor R4, and equal to Rt2; the voltage signal VIN output by the digital-to-analog converter 12 is V1. It should be noted that the voltage signal VIN output by the digital-to-analog converter 12 is also the voltage signal received by the voltage-to-current circuit 13. The current signal I output by the voltage-to-current circuit 13 is also the current value output to the feedback resistor R6 and the load 14. The current signal output by the voltage-to-current circuit 13 is equal to the product of the ratio of the voltage signal VIN received by the voltage-to-current circuit 13 to the feedback resistor R6 and the ratio of the third resistor R3 to the first resistor R1; and equal to the product of the ratio of the voltage signal VIN received by the voltage-to-current circuit 13 to the feedback resistor R6 and the ratio of the fourth resistor R4 to the second resistor R2.

[0041] That is, R1=R2=Rt1, R3=R4=Rt2, VIN=V1;

[0042] Then the output current I=(V1 / R6)×(Rt2 / Rt1).

[0043] In this embodiment, the current expansion transistor Q1 is an NPN type transistor.

[0044] In some embodiments, the constant-voltage-to-current circuit 15 comprises a compensation transistor Q2 and a third amplifier U1C.

[0045] The positive input terminal of the third amplifier U1C is connected with the output terminal of the voltage-to-constant current circuit 13 and the load 14, specifically, the positive input terminal of the third amplifier U1C is connected with the feedback resistor R6 in the voltage-to-constant current circuit 13 and the load resistor RL2. The negative input terminal of the third amplifier U1C is connected with the emitter of the compensation transistor Q2, and the negative input terminal of the third amplifier U1C is connected with the base of the compensation transistor Q2. The collector of the compensation transistor Q2 is connected with the input terminal of the Buck circuit 16.

[0046] In the embodiment, the collector of the compensation transistor Q2 is connected with the input terminal of the Buck circuit 16. The Buck circuit 16 outputs a dynamic control voltage POWER according to the feedback signal received by the input terminal.

[0047] In some embodiments, the voltage-to-constant current circuit 15 further comprises a seventh resistor R7, an eighth resistor R8, a ninth resistor R9, and a tenth resistor R10 connected with the compensation transistor Q2. Specifically, the base of the compensation transistor Q2 is further connected with the seventh resistor R7 and the eighth resistor R8, respectively, the emitter of the compensation transistor Q2 is connected with the ninth resistor R9, and the collector of the compensation transistor Q2 is connected with the tenth resistor R10. Specifically, the base of the compensation transistor Q2 is connected with the output terminal of the Buck circuit 16 through the seventh resistor R7 and is grounded through the eighth resistor R8. The emitter of the compensation transistor Q2 is connected with the output terminal of the Buck circuit 16 through the ninth resistor R9. The collector of the compensation transistor Q2 is grounded through the tenth resistor R10.

[0048] In some embodiments, the Buck circuit 16 comprises a DC-DC module U2, the input terminal FB of the DC-DC module U2 is the negative input terminal of the Buck circuit 16, and the voltage of the input terminal FB is Vfb. According to the virtual short of the third amplifier U1C, the base voltage of the compensation transistor Q2 is equal to the voltage on the load resistor RL2. Therefore, the voltage VPOWER output by the Buck circuit 16 is (R9 / R10)Vfb+VRL2.

[0049] In the embodiment, the voltage-to-constant current circuit 15 further comprises a compensation diode D2 arranged between the third amplifier U1C and the compensation transistor Q2. Specifically, the positive electrode of the compensation diode D2 is connected with the output terminal of the third amplifier U1C, and the negative electrode of the compensation diode D2 is connected with the base of the compensation transistor Q2. The compensation diode D2 is used to control the flow direction of the signal.

[0050] In some embodiments, the compensation transistor Q2 is a PNP type transistor.

[0051] In some embodiments, the minimum control voltage output by the DC-DC module U2 is controlled by the voltage on the load resistor RL2. When the voltage on the load resistor RL2 is 0V, the output control voltage is X, and the calculation formula is VPOWER≈((R9 / R10)Vfb+0.7V)(1+R8 / R7)=X.

[0052] The minimum output voltage is set on the seventh resistor R7 and the eighth resistor R8, and the minimum control voltage X needs to be greater than the voltage on the load resistor RL2 + the feedback resistor R6 + the voltage on the current expansion transistor Q1, so that the current expansion transistor Q1 is not in a saturated state, and the current expansion transistor Q1 reserves a little voltage, which is beneficial to the smooth output of the dynamic voltage. The amplification ratio of the compensation transistor Q2 is adjusted by the ninth resistor R9 and the tenth resistor R10, and then the relationship ratio of the control voltage VPOWER and the input voltage of the third amplifier U1C is set.

[0053] Compared with the traditional constant voltage to constant current circuit, the output voltage is constant, and when the load is small, the excess voltage is consumed between the collector and the emitter of the current expansion transistor Q1. In the present application, the output voltage is a dynamic voltage, and the size of the POWER output depends on the size of the load. When the load is small, the voltage on the load resistor RL2 is detected to be small, and the control voltage POWER output by the DC-DC module U2 is a small voltage. In the present embodiment, the constant voltage to constant current circuit 15 is a full dynamic follower, and the output changes are timely adjusted to change the dynamic voltage, and the dynamic characteristic is good. Moreover, the seventh resistor R7 and the eighth resistor R8 can set the minimum output value, which is beneficial to the stability of the dynamic voltage output at different voltages. The compensation diode D2 can compensate the junction voltage of the compensation transistor Q2 connected thereto, so that the output control voltage is 0V.

[0054] The present application also provides a power consumption reduction system, which comprises the dynamic voltage output circuit in any of the above embodiments.

[0055] The beneficial effects in the present application are that the voltage value on the load is collected by the constant voltage to constant current circuit, and then the control voltage of the current expansion transistor in the constant voltage to constant current circuit is adjusted according to the collected voltage value by the Buck circuit, so as to reduce the loss of the voltage signal in the constant voltage to constant current circuit, and solve the problem of serious heating of the power supply system when the load is small.

[0056] The above is only an embodiment of the present application, and does not limit the patent scope of the present application. Any equivalent structure or equivalent flow transformation by using the content of the specification and the drawings, or direct or indirect application in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A dynamic voltage output circuit, characterized by, The dynamic voltage output circuit comprises: a controller for providing a control signal; a digital-to-analog converter connected to an output terminal of the controller for converting the control signal into a voltage signal; a voltage-to-constant current circuit connected to an output terminal of the digital-to-analog converter for converting the voltage signal into a current signal; a load connected to an output terminal of the voltage-to-constant current circuit; a constant voltage-to-constant current circuit connected to the load for collecting an output voltage of the load; a Buck circuit connected to the constant voltage-to-constant current circuit and the voltage-to-constant current circuit respectively for adjusting a control voltage output to the voltage-to-constant current circuit according to the output voltage of the load collected by the constant voltage-to-constant current circuit.

2. The dynamic voltage output circuit of claim 1, wherein, The control voltage is proportional to the output voltage of the load.

3. The dynamic voltage output circuit of claim 1, wherein, The voltage-to-constant current circuit comprises at least a current expansion transistor, a first amplifier and a feedback resistor; a base of the current expansion transistor is connected to an output terminal of the first amplifier, a collector of the current expansion transistor is connected to an output terminal of the Buck circuit, an emitter of the current expansion transistor is connected to the load through the feedback resistor, and a voltage difference between the collector and the emitter of the current expansion transistor is adjusted by the control voltage output by the Buck circuit; wherein the current expansion transistor is an NPN transistor.

4. The dynamic voltage output circuit of claim 3, wherein, The voltage-to-constant current circuit further comprises a second amplifier, a first resistor, a second resistor, a third resistor, a fourth resistor and a fifth resistor; a positive input terminal of the first amplifier is connected to an output terminal of the digital-to-analog converter through the first resistor and connected to an output terminal of the second amplifier through the second resistor; a negative input terminal of the first amplifier is connected to the third resistor and connected to the feedback resistor and the emitter of the current expansion transistor through the fourth resistor, and an output terminal of the first amplifier is connected to the base of the current expansion transistor through the fifth resistor; wherein a positive input terminal of the second amplifier is connected to the load, and a negative input terminal of the second amplifier is connected to the output terminal of the second amplifier.

5. The dynamic voltage output circuit of claim 4, wherein, The first resistor and the second resistor have the same resistance, and the third resistor and the fourth resistor have the same resistance; a current signal I output by the voltage-to-constant current circuit is (VIN / R6)×(Rt2 / Rt1); wherein VIN is a voltage signal received by the voltage-to-constant current circuit, R6 is a resistance of the feedback resistor, Rt1 is a resistance of the first resistor or the second resistor, and Rt2 is a resistance of the third resistor or the fourth resistor.

6. The dynamic voltage output circuit of claim 1, wherein, The constant voltage-to-constant current circuit comprises a compensation transistor and a third amplifier; a positive input terminal of the third amplifier is connected to an output terminal of the voltage-to-constant current circuit and the load, a negative input terminal of the third amplifier is connected to an emitter of the compensation transistor, and an output terminal of the third amplifier is connected to a base of the compensation transistor; a collector of the compensation transistor is connected to an input terminal of the Buck circuit.

7. The dynamic voltage output circuit of claim 6, wherein, The constant voltage-to-constant current circuit further comprises a seventh resistor, an eighth resistor, a ninth resistor and a tenth resistor. The base of the compensation triode is connected with the seventh resistor and the eighth resistor respectively; the emitter of the compensation triode is connected with the ninth resistor, and the collector of the compensation triode is connected with the tenth resistor. The control voltage is related to the ratio of the ninth resistor and the tenth resistor.

8. The dynamic voltage output circuit of claim 7, wherein, The constant-voltage-to-constant-current circuit further comprises a compensation diode, the positive electrode of the compensation diode is connected with the output end of the third amplifier, and the negative electrode of the compensation diode is connected with the base of the compensation triode.

9. The dynamic voltage output circuit of claim 7, wherein, The compensation triode is a PNP type triode.

10. A system for reducing power consumption, the system comprising: The dynamic voltage output circuit comprises the constant-voltage-to-constant-current circuit according to any one of claims 1 to 9.

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