A positive and negative power supply control circuit for an AC / DC conversion module

Abstract

The present invention discloses a positive and negative power supply control circuit of an AC / DC conversion module, comprising an eighth resistor, a first operational amplifier, a second inverter, a third digital potentiometer, a fourth digital potentiometer, a first triode, a second triode, a first conversion switch, a first diode, a second diode, a first capacitor, a second capacitor, a first connector, a second connector, and a sixth connector. The inverting end of the first operational amplifier is connected to one end of the eighth resistor, the output end of the first operational amplifier is connected to the base of the first triode and the input end of the second inverter, and the collector of the first triode is connected to the sixth connector and the third pin of the third digital potentiometer.

Description

Technical Field

[0001] The invention relates to the technical field of power supply, and in particular to a positive and negative power supply control circuit of an AC / DC conversion module. Background Art

[0002] Alternating voltage is positive and negative in one cycle. When some loads need DC power supply, the AC signal can be output in one direction when it is alternating between positive and negative through a rectifier diode to complete the AC-to-DC conversion. However, some loads need to provide positive and negative power signals to complete the transmission. For example, when using the handshake protocol, CP confirms the connection and feedback through the voltage drop of the positive voltage, and the negative voltage confirms the actual driving state. The existing AC-DC conversion module can only provide a power signal output, which cannot meet the scenario that requires positive and negative power conversion. Summary of the invention

[0003] In view of the above technical problems, the purpose of the present invention is to provide a positive and negative power supply control circuit of an AC / DC conversion module, including an eighth resistor R8, a first operational amplifier U1, a second inverter U2, a third digital potentiometer U3, a fourth digital potentiometer U4, a first transistor Q1, a second transistor Q2, a first conversion switch RL1, a first diode D1, a second diode D2, a first capacitor C1, a second capacitor C2, a first connector P1, a second connector P2, and a sixth connector P6, wherein the inverting end of the first operational amplifier U1 is connected to one end of the eighth resistor R8, the in-phase end of the first operational amplifier U1 is connected to the pulse signal, the output end of the first operational amplifier U1 is connected to the base of the first transistor Q1 and the input end of the second inverter U2, the collector of the first transistor Q1 is connected to the sixth connector P6, and the third pin of the third digital potentiometer U3 is connected to the collector of the first transistor Q1. The fifth pin of the third digital potentiometer U3 and the sixth pin of the third digital potentiometer U3 are connected to the first connector P1 and the first connection end of the first conversion switch RL1. The second connection end of the first conversion switch RL1 is connected to the second connector P2, the fifth pin of the fourth digital potentiometer U4 and the sixth pin of the fourth digital potentiometer U4 are connected. The third pin of the fourth digital potentiometer U4 is connected to one end of the second capacitor C2 and the anode of the first diode D1. The cathode of the first diode D1 is connected to one end of the first capacitor C1 and the anode of the second diode D2. The other end of the first capacitor C1 is connected to the emitter of the first transistor Q1 and the collector of the second transistor Q2. The base of the second transistor Q2 is connected to the output end of the second inverter U2. The other end of the eighth resistor R8, the other end of the second capacitor C2, the cathode of the second diode D2, the emitter of the second transistor Q2 and the ground are connected.

[0004] Furthermore, it also includes a first resistor R1, a second resistor R2, a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, a ninth resistor R9, a fifth operational amplifier U5, a sixth RS trigger U6, a seventh operational amplifier U7, a third transistor Q3, a third connector P3, a fifth connector P5, a third diode D3, a fourth diode D4, and a second relay RL2, wherein one end of the first resistor R1 and one end of the fifth resistor R5 are connected to the first connector P1, the other end of the fifth resistor R5 is connected to one end of the seventh resistor R7, the inverting end of the fifth operational amplifier U5, and the inverting end of the seventh operational amplifier U7, the output end of the fifth operational amplifier U5 is connected to one end of the coil of the first conversion switch RL1, the in-phase end of the fifth operational amplifier U5 is connected to the anode of the fourth diode D4 and the emitter of the third transistor Q3, the collector of the third transistor Q3 is connected to the cathode of the fourth diode D4, the in-phase end of the seventh operational amplifier U7, and the fifth connector P5, and the third transistor Q3 is connected. The base is connected to one end of the coil of the second relay RL2 and the fifth pin of the sixth RS trigger U6, the other end of the coil of the second relay RL2 is connected to the other end of the coil of the first conversion switch RL1 and the ground, one end of the second relay RL2 is connected to the third connector P3, the other end of the second relay RL2 is connected to the common end of the first conversion switch RL1, the output end of the seventh operational amplifier U7 is connected to one end of the ninth resistor R9 and the third pin of the sixth RS trigger U6, the first pin of the sixth RS trigger U6 is connected to the power supply, the second pin of the sixth RS trigger U6 and the sixth pin of the sixth RS trigger U6 are connected to the anode of the third diode D3, the cathode of the third diode D3 is connected to one end of the sixth resistor R6 and the fourth pin of the sixth RS trigger U6, one end of the second resistor R2 is connected to the second connector P2, the other end of the first resistor R1, the other end of the second resistor R2, the other end of the sixth resistor R6, the other end of the seventh resistor R7, the other end of the ninth resistor R9 are connected to the ground.

[0005] Furthermore, it also includes a third resistor R3 and a fourth resistor R4, one end of the third resistor R3 is connected to the second pin of the third digital potentiometer U3 and the second pin of the fourth digital potentiometer U4, one end of the fourth resistor R4 is connected to the seventh pin of the third digital potentiometer U3 and the seventh pin of the fourth digital potentiometer U4, and the other end of the third resistor R3 and the other end of the fourth resistor R4 are connected to the ground.

[0006] Furthermore, it also includes a first switch SW1, a second switch SW2, an eighth inverter U8, and a fifth diode D5, wherein one end of the first switch SW1 and one end of the second switch SW2 are connected to a power supply, the other end of the first switch SW1 is connected to an input end of the eighth inverter U8 and a cathode of the fifth diode D5, an anode of the fifth diode D5 is connected to a second pin of the third digital potentiometer U3 and the other end of the second switch SW2, an output end of the eighth inverter U8 is connected to a seventh pin of the third digital potentiometer U3, and a first pin of the third digital potentiometer U3, a first pin of the fourth digital potentiometer U4 and a common-mode end of the first operational amplifier U1 are connected.

[0007] Furthermore, it also includes a fourth connector P4, and the fourth connector P4 is connected to the cathode of the third diode D3.

[0008] Furthermore, it also includes a rectifier circuit, wherein the rectifier circuit output end is connected to the sixth connector P6.

[0009] Furthermore, the signal input to the non-inverting terminal of the first operational amplifier U1 is a high-frequency pulse signal.

[0010] The beneficial effects of the present invention compared with the prior art are:

[0011] It can provide two power signal outputs after AC to DC conversion, and after changing the AC input, it can automatically detect whether the I / O port output of the chip is in a normal driving state when powered on. It will supply power when it is normal, and disconnect the load power supply when it is abnormal to prevent failures. It can provide reset during online adjustment and has power-off and non-power-off detection methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the prior art and the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0013] Figure 1 A schematic diagram of the circuit structure provided by the present invention. DETAILED DESCRIPTION

[0014] In order to make the objects and advantages of the present invention more clearly understood, the present invention is specifically described below in conjunction with embodiments. It should be understood that the following text is only used to describe one or several specific implementations of the present invention, and does not strictly limit the scope of protection specifically requested by the present invention.

[0015] The present invention discloses a positive and negative power supply control circuit of an AC / DC conversion module, comprising an eighth resistor R8, a first operational amplifier U1, a second inverter U2, a third digital potentiometer U3, a fourth digital potentiometer U4, a first transistor Q1, a second transistor Q2, a first conversion switch RL1, a first diode D1, a second diode D2, a first capacitor C1, a second capacitor C2, a first connector P1, a second connector P2, and a sixth connector P6, wherein the inverting end of the first operational amplifier U1 is connected to one end of the eighth resistor R8, the in-phase end of the first operational amplifier U1 is connected to a pulse signal, the output end of the first operational amplifier U1 is connected to the base of the first transistor Q1 and the input end of the second inverter U2, the collector of the first transistor Q1 is connected to the sixth connector P6 and the third pin of the third digital potentiometer U3, and the third digital potentiometer U4 is connected to the collector of the first transistor Q1. The fifth pin of the digital potentiometer U3 and the sixth pin of the third digital potentiometer U3 are connected to the first connector P1 and the first connection end of the first conversion switch RL1; the second connection end of the first conversion switch RL1 is connected to the second connector P2, the fifth pin of the fourth digital potentiometer U4, and the sixth pin of the fourth digital potentiometer U4 are connected; the third pin of the fourth digital potentiometer U4 is connected to one end of the second capacitor C2 and the anode of the first diode D1; the cathode of the first diode D1 is connected to one end of the first capacitor C1 and the anode of the second diode D2; the other end of the first capacitor C1 is connected to the emitter of the first transistor Q1 and the collector of the second transistor Q2; the base of the second transistor Q2 is connected to the output end of the second inverter U2; the other end of the eighth resistor R8, the other end of the second capacitor C2, the cathode of the second diode D2, the emitter of the second transistor Q2 and the ground end are connected.

[0016] Specifically, it also includes a first resistor R1, a second resistor R2, a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, a ninth resistor R9, a fifth operational amplifier U5, a sixth RS trigger U6, a seventh operational amplifier U7, a third transistor Q3, a third connector P3, a fifth connector P5, a third diode D3, a fourth diode D4, and a second relay RL2. One end of the first resistor R1 and one end of the fifth resistor R5 are connected to the first connector P1. The other end of the fifth resistor R5 is connected to one end of the seventh resistor R7, the inverting end of the fifth operational amplifier U5, and the inverting end of the seventh operational amplifier U7. The output end of the fifth operational amplifier U5 is connected to one end of the coil of the first conversion switch RL1. The in-phase end of the fifth operational amplifier U5 is connected to the anode of the fourth diode D4 and the emitter of the third transistor Q3. The collector of the third transistor Q3 is connected to the cathode of the fourth diode D4, the in-phase end of the seventh operational amplifier U7, and the fifth connector P5. The base is connected to one end of the coil of the second relay RL2 and the fifth pin of the sixth RS trigger U6, the other end of the coil of the second relay RL2 is connected to the other end of the coil of the first conversion switch RL1 and the ground, one end of the second relay RL2 is connected to the third connector P3, the other end of the second relay RL2 is connected to the common end of the first conversion switch RL1, the output end of the seventh operational amplifier U7 is connected to one end of the ninth resistor R9 and the third pin of the sixth RS trigger U6, the first pin of the sixth RS trigger U6 is connected to the power supply, the second pin of the sixth RS trigger U6 and the sixth pin of the sixth RS trigger U6 are connected to the anode of the third diode D3, the cathode of the third diode D3 is connected to one end of the sixth resistor R6 and the fourth pin of the sixth RS trigger U6, one end of the second resistor R2 is connected to the second connector P2, the other end of the first resistor R1, the other end of the second resistor R2, the other end of the sixth resistor R6, the other end of the seventh resistor R7, the other end of the ninth resistor R9 are connected to the ground.

[0017] Specifically, it also includes a third resistor R3 and a fourth resistor R4, one end of the third resistor R3 is connected to the second pin of the third digital potentiometer U3 and the second pin of the fourth digital potentiometer U4, one end of the fourth resistor R4 is connected to the seventh pin of the third digital potentiometer U3 and the seventh pin of the fourth digital potentiometer U4, and the other end of the third resistor R3 and the other end of the fourth resistor R4 are connected to the ground.

[0018] Specifically, it also includes a first switch SW1, a second switch SW2, an eighth inverter U8, and a fifth diode D5. One end of the first switch SW1 is connected to one end of the second switch SW2 and a power supply. The other end of the first switch SW1 is connected to the input end of the eighth inverter U8 and the cathode of the fifth diode D5. The anode of the fifth diode D5 is connected to the second pin of the third digital potentiometer U3 and the other end of the second switch SW2. The output end of the eighth inverter U8 is connected to the seventh pin of the third digital potentiometer U3. The first pin of the third digital potentiometer U3, the first pin of the fourth digital potentiometer U4 and the in-phase end of the first operational amplifier U1 are connected.

[0019] Specifically, a fourth connector P4 is further included, and the fourth connector P4 is connected to the cathode of the third diode D3.

[0020] Specifically, it also includes a rectifier circuit, and the output end of the rectifier circuit is connected to the sixth connector P6.

[0021] Specifically, the signal input to the non-inverting terminal of the first operational amplifier U1 is a high-frequency pulse signal.

[0022] Considering that the output of AC after conversion to DC can only output one power supply signal, the positive power supply output signal is first input to the sixth connector P6 after AC rectification, and the pulse signal is input to the in-phase terminal of the first operational amplifier U1 at the same time. When the level is high, the first operational amplifier U1 outputs, and the signal is fed back to the base of the first transistor Q1 in one way, and is output to the base of the second transistor Q2 after passing through the second inverter U2 in the other way. The second transistor Q2 is cut off. When the first transistor Q1 is turned on to the sixth connector P6, the signal is input to the positive electrode of the first capacitor C1 through the collector and emitter of the first transistor Q1, and the negative electrode is looped through the second diode D2, and the first diode D1 is cut off, and the first capacitor C1 completes energy storage. When the level is low, the first operational amplifier U 1 output is input to the base of the second transistor Q2 after passing through the second inverter U2, the second transistor Q2 is turned on and the first transistor Q1 is turned off, the positive electrode of the first capacitor C1 passes through the second transistor Q2 loop, the second capacitor C2 freewheels through the first diode D1 and is input to the first capacitor C1, the second diode D2 is turned off, the second capacitor C2 outputs a negative power signal to the second connector P2, the first connector P1 and the second connector P2 and the first conversion switch RL1, and then output by the first conversion switch RL1. The coil of the first conversion switch RL1 is directly connected to the I / O of the chip for control in this embodiment, and the chip is not shown in the attached drawings. In this embodiment, the third digital potentiometer U3 and the fourth digital potentiometer U4 are ordinary adjustable resistors.

[0023] Taking into account that the input of different AC voltages will cause changes in the rectified reference voltage, when the amplitude of the control signal of the chip input conversion switch is lower than the reference voltage sampled by it, it will cause a load control failure. Therefore, the I / O port of the chip is removed to directly control the first conversion switch RL1, and the control is performed by the output of the fifth operational amplifier U5. When the AC signal is replaced and the power is turned on, the detection signal is input by the fifth connector P5, and the fifth operational amplifier U5 outputs the control signal of the first conversion switch RL1. However, when the fifth connector P5 is input, it is reverse biased through the fourth diode D4. If the voltage after sampling and rectification of the fifth resistor R5 and the seventh resistor R7 is lower than the input of the fifth connector P5, the seventh operational amplifier U7 outputs to the third pin of the sixth RS trigger U6. In the initial state, the sixth RS trigger U6 outputs to the sixth pin, and the signal is fed back to the second pin one way and fed back to the fourth pin one way through the third diode D3 and the sixth resistor R6. The sixth RS trigger U6 is not set. When the seventh operational amplifier U7 outputs a signal, the fifth pin of the sixth RS trigger U6 outputs The output signal is sent to the third transistor Q3, and the third transistor Q3 is turned on. The signal of the fifth connector P5 can be fed back to the fifth operational amplifier U5 through the third transistor Q3. At the same time, the sixth pin level of the sixth RS trigger U6 is cut off, and the sixth RS trigger U6 is set to lock the seventh operational amplifier U7 input and the sixth RS trigger U6 switching. If the voltage after sampling and rectification of the fifth resistor R5 and the seventh resistor R7 is higher than the input of the fifth connector P5, the fifth pin of the sixth RS trigger U6 has no output, the third transistor Q3 is cut off, and at the same time, the second relay RL2 is cut off to disconnect the connection between the first conversion switch RL1 and the second relay RL2, and the third connector P3 has no signal output. That is to say, when the reference voltage changes and the power is turned on, it is detected whether the I / O drive can drive the conversion switch to switch normally. Considering the online adjustment of the AC signal, a reset signal is provided through the fourth connector P4. While adjusting, the input signal of the fourth connector P4 is released to unlock the sixth RS trigger U6 to complete the reset, and wait for the fifth connector P5 to input a signal again.

[0024] Taking into account the output adjustment of the positive and negative power supply signals after rectification, when the chip and manual adjustment are switched and controlled, the two manual adjustment signals of the first switch SW1 and the second switch SW2 can be input through the eighth inverter U8, and the third resistor R3 and the fourth resistor R4 replace the chip to pull down the signal. When no adjustment is performed, the eighth inverter U8 outputs a high-level signal to the fifth pin of the third digital potentiometer U3 and the fourth digital potentiometer U4 to sleep. When any input is made, the third digital potentiometer U3 and the fourth digital potentiometer U4 wake up and control the second pin state of the third digital potentiometer U3 and the fourth digital potentiometer U4 according to the input of the first switch SW1 and the second switch SW2. When the first switch SW1 signal is input, the fifth diode D5 is reverse biased. The automatic control is consistent with the manual control principle. The I / O ports of the two signal outputs are connected to the other end of the first switch SW1 and the other end of the second switch SW2 to complete the control. In this embodiment, the third digital potentiometer U3 and the fourth digital potentiometer U4 are used as adjustable digital potentiometers.

[0025] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations within the meaning and scope of the equivalent elements of the claims be included in the invention. Any marking in a claim should not be considered as limiting the claim to which it relates.

Claims

1. A positive and negative power supply control circuit of an AC / DC conversion module, characterized in that: The device comprises an eighth resistor, a first operational amplifier, a second inverter, a third digital potentiometer, a fourth digital potentiometer, a first triode, a second triode, a first conversion switch, a first diode, a second diode, a first capacitor, a second capacitor, a first connector, a second connector, and a sixth connector. The inverting end of the first operational amplifier is connected to one end of the eighth resistor, the in-phase end of the first operational amplifier is connected to the pulse signal, the output end of the first operational amplifier is connected to the base of the first triode and the input end of the second inverter, the collector of the first triode is connected to the sixth connector and the third pin of the third digital potentiometer, the fifth pin of the third digital potentiometer and the third pin of the third digital potentiometer are connected, and the output end of the first operational amplifier is connected to the base of the first triode and the input end of the second inverter. The sixth pin of the digital potentiometer is connected to the first connector and the normally open end of the first conversion switch, the normally closed end of the first conversion switch is connected to the second connector, the fifth pin of the fourth digital potentiometer, and the sixth pin of the fourth digital potentiometer, the third pin of the fourth digital potentiometer is connected to one end of the second capacitor and the anode of the first diode, the cathode of the first diode is connected to one end of the first capacitor and the anode of the second diode, the other end of the first capacitor is connected to the emitter of the first transistor and the collector of the second transistor, the base of the second transistor is connected to the output end of the second inverter, and the other end of the eighth resistor, the other end of the second capacitor, the cathode of the second diode, the emitter of the second transistor and the ground end are connected.

2. The positive and negative power supply control circuit of the AC / DC conversion module according to claim 1, characterized in that: It also includes a first resistor, a second resistor, a fifth resistor, a sixth resistor, a seventh resistor, a ninth resistor, a fifth operational amplifier, a sixth RS trigger, a seventh operational amplifier, a third transistor, a third connector, a fifth connector, a third diode, a fourth diode, and a second relay. One end of the first resistor and one end of the fifth resistor are connected to the first connector. The other end of the fifth resistor is connected to one end of the seventh resistor, the inverting end of the fifth operational amplifier, and the inverting end of the seventh operational amplifier. The output end of the fifth operational amplifier is connected to one end of the first conversion switch coil. The in-phase end of the fifth operational amplifier is connected to the anode of the fourth diode and the emitter of the third transistor. The collector of the third transistor is connected to the cathode of the fourth diode, the in-phase end of the seventh operational amplifier, and the fifth connector. The base of the third transistor and the second relay are connected. One end of the device coil is connected to the fifth pin of the sixth RS trigger, the other end of the second relay coil is connected to the other end of the first conversion switch coil and the ground end, one end of the second relay is connected to the third connector, the other end of the second relay is connected to the common end of the first conversion switch, the output end of the seventh operational amplifier is connected to one end of the ninth resistor and the third pin of the sixth RS trigger, the first pin of the sixth RS trigger is connected to the power supply, the second pin of the sixth RS trigger, the sixth pin of the sixth RS trigger is connected to the anode of the third diode, the cathode of the third diode is connected to one end of the sixth resistor and the fourth pin of the sixth RS trigger, one end of the second resistor is connected to the second connector, and the other end of the first resistor, the other end of the second resistor, the other end of the sixth resistor, the other end of the seventh resistor, the other end of the ninth resistor are connected to the ground end.

3. The positive and negative power supply control circuit of the AC / DC conversion module according to claim 1, characterized in that: It also includes a third resistor and a fourth resistor, one end of the third resistor is connected to the second pin of the third digital potentiometer and the second pin of the fourth digital potentiometer, one end of the fourth resistor is connected to the seventh pin of the third digital potentiometer and the seventh pin of the fourth digital potentiometer, and the other end of the third resistor and the other end of the fourth resistor are connected to the ground.

4. The positive and negative power supply control circuit of the AC / DC conversion module according to claim 3, characterized in that: It also includes a first switch, a second switch, an eighth inverter, and a fifth diode, wherein one end of the first switch is connected to one end of the second switch and a power supply, the other end of the first switch is connected to the input end of the eighth inverter and the cathode of the fifth diode, the anode of the fifth diode is connected to the second pin of the third digital potentiometer and the other end of the second switch, the output end of the eighth inverter is connected to the seventh pin of the third digital potentiometer, and the first pin of the third digital potentiometer, the first pin of the fourth digital potentiometer and the in-phase end of the first operational amplifier are connected.

5. The positive and negative power supply control circuit of the AC / DC conversion module according to claim 2, characterized in that: The device further includes a fourth connector, wherein the fourth connector is connected to the cathode of the third diode.

6. The positive and negative power supply control circuit of the AC / DC conversion module according to claim 1, characterized in that: It also includes a rectifier circuit, wherein the rectifier circuit output end is connected to the sixth connector.

7. The positive and negative power supply control circuit of the AC / DC conversion module according to claim 1, characterized in that: The signal input to the non-inverting terminal of the first operational amplifier is a high-frequency pulse signal.

Images