A DC motor H-bridge mutually exclusive drive circuit

Abstract

The invention discloses a DC motor H-bridge mutually exclusive driving circuit, comprising a forward driving module for receiving a forward command and a reverse driving module for receiving a reverse command, and also comprising a forward command processing module, a reverse command processing module and a command interlocking module, wherein the input end of the forward command processing module inputs the forward command, the forward output end of the forward command processing module is connected to the forward input end of the command interlocking module, the forward drive output end of the command interlocking module is connected to the input end of the forward drive module, the input end of the reverse command processing module inputs the reverse command, the reverse output end of the reverse command processing module is connected to the reverse input end of the command interlocking module, and the reverse drive output end of the command interlocking module is connected to the input end of the reverse drive module. The invention invalidates one of the forward and reverse commands by adding a command interlocking module when the forward and reverse commands are given at the same time, thereby avoiding circuit damage and improving circuit reliability.

Description

Technical Field

[0001] The invention relates to a driving circuit of a direct current motor, and in particular to an H-bridge mutually exclusive driving circuit of a direct current motor. Background Art

[0002] Existing DC motor drivers usually use an H-bridge drive circuit, which uses four MOS tubes or power transistors (see Figure 1 S1-S4) and DC motor (see Figure 1 The M) forms an H-bridge circuit structure, and controls the motor to rotate forward or reverse through two mutually exclusive control instructions. The forward drive module, the reverse drive module, the DC motor and four MOS tubes or power transistors together constitute the H-bridge circuit module.

[0003] The four MOS tubes or power transistors of the H-bridge circuit cannot be turned on at the same time, otherwise the circuit will be burned out due to short circuit. Therefore, the two control instructions must be mutually exclusive, that is, only one control instruction can take effect at the same time.

[0004] The traditional DC motor H-bridge drive circuit directly inputs two mutually exclusive control instructions, namely the forward instruction and the reverse instruction, into the forward drive module and the reverse drive module respectively, without interlocking the forward instruction and the reverse instruction in the circuit. The operating safety of the DC motor is guaranteed by the accuracy of the control instruction. Once an error occurs in the control instruction, the circuit will be damaged and the DC motor will malfunction, so the safety is insufficient.

[0005] In addition, the traditional DC motor H-bridge drive circuit has only one threshold for its instructions, that is, the instruction voltage is higher than the threshold, the instruction is valid, and lower than the threshold, the instruction is invalid. When the instruction voltage is unstable, especially when the voltage fluctuates near the threshold voltage, the output of the entire H-bridge circuit will also fluctuate, causing frequent starting and stopping of the motor, and in severe cases, causing damage to the motor. Summary of the invention

[0006] The purpose of the present invention is to solve the above problem and provide a DC motor H-bridge mutually exclusive driving circuit in which only one forward rotation instruction and one reverse rotation instruction can be effective at the same time.

[0007] The present invention achieves the above-mentioned purpose through the following technical solutions:

[0008] A DC motor H-bridge mutually exclusive drive circuit comprises a forward drive module receiving a forward command and a reverse drive module receiving a reverse command, and further comprises a forward command processing module, a reverse command processing module and a command interlocking module, wherein the input end of the forward command processing module inputs the forward command, the forward output end of the forward command processing module is connected to the forward input end of the command interlocking module, the forward drive output end of the command interlocking module is connected to the input end of the forward drive module, the input end of the reverse command processing module inputs the reverse command, and the reverse command processing module receives the reverse command. The inversion output end is connected to the inversion input end of the instruction interlock module, and the inversion drive output end of the instruction interlock module is connected to the input end of the inversion drive module; the instruction interlock module includes a twenty-second resistor, a twenty-third resistor, a thirty-eighth resistor, a thirty-ninth resistor, a ninth diode, a tenth diode, a twelfth diode, a fourteenth diode, a sixteenth diode, a seventeenth diode, an eighth NPN transistor and a fifteenth NPN transistor, the first end of the twenty-second resistor is connected to the positive electrode of the twelfth diode and serves as the forward input end of the instruction interlock module, The second end of the twenty-second resistor is connected to the anode of the ninth diode, the cathode of the ninth diode is respectively connected to the base of the eighth NPN transistor and the first end of the twenty-third resistor, the collector of the eighth NPN transistor is connected to the cathode of the tenth diode, the cathode of the twelfth diode is connected to the anode of the fourteenth diode and serves as the forward drive output end of the instruction interlock module, the first end of the thirty-eighth resistor is connected to the anode of the seventeenth diode and serves as the inverting input end of the instruction interlock module, and the second end of the thirty-eighth resistor is connected to the cathode of the seventeenth diode. The anode of the sixteenth diode is connected, the cathode of the sixteenth diode is respectively connected to the base of the fifteenth NPN transistor and the first end of the thirty-ninth resistor, the collector of the fifteenth NPN transistor is connected to the cathode of the fourteenth diode, the cathode of the seventeenth diode is connected to the anode of the tenth diode and serves as the reverse drive output end of the instruction interlock module, and the second end of the twenty-third resistor, the emitter of the eighth NPN transistor, the second end of the thirty-ninth resistor and the emitter of the fifteenth NPN transistor are all connected to the negative electrode of the power supply.

[0009] Further, a first capacitor is connected between the first end of the twenty-second resistor and the second end of the twenty-third resistor, and a third capacitor is connected between the first end of the thirty-eighth resistor and the second end of the thirty-ninth resistor.

[0010] Preferably, the forward instruction processing module includes an eleventh diode, an eighteenth voltage-stabilizing diode, a fifteenth resistor, a sixteenth resistor, a seventeenth resistor, an eighteenth resistor, a nineteenth resistor, a twentieth resistor, a twenty-first resistor, a twenty-fourth resistor, a twenty-fifth resistor, a twenty-sixth resistor, a twenty-seventh resistor, a seventh PNP transistor, a ninth NPN transistor, a tenth NPN transistor and an eleventh NPN transistor, and the reverse instruction processing module includes a fifteenth diode, a thirteenth voltage-stabilizing diode, a forty-sixth resistor, a forty-seventh resistor, a twenty-eighth resistor, a twenty-ninth resistor, a thirty-first resistor, a thirty-second resistor, a a thirty-third resistor, a thirty-fourth resistor, a thirty-fifth resistor, a thirty-sixth resistor, a thirty-seventh resistor, a fourteenth PNP transistor, a twelfth NPN transistor, a thirteenth NPN transistor and a sixteenth NPN transistor; the anode of the eleventh diode is the input end of the forward instruction processing module, the cathode of the eleventh diode is connected to the first end of the twenty-fourth resistor, the second end of the twenty-fourth resistor is connected to the base of the ninth NPN transistor, the collector of the ninth NPN transistor is respectively connected to the first end of the sixteenth resistor and the first end of the nineteenth resistor, and the second end of the sixteenth resistor is respectively connected to the first end of the sixteenth resistor. The cathode of the eighteenth zener diode, the first end of the fifteenth resistor and the first end of the seventeenth resistor are connected, the emitter of the ninth NPN transistor is respectively connected to the emitter of the tenth NPN transistor and the first end of the twenty-fifth resistor, the base of the tenth NPN transistor is respectively connected to the second end of the nineteenth resistor, the collector of the tenth NPN transistor is respectively connected to the second end of the seventeenth resistor and the first end of the twentieth resistor, the second end of the twentieth resistor is connected to the base of the seventh PNP transistor, the emitter of the seventh PNP transistor, the second end of the fifteenth resistor and the first end of the twenty-fifth resistor are respectively connected The first end of the eighteenth resistor, the first end of the twenty-eighth resistor, the first end of the twenty-ninth resistor and the emitter of the fourteenth PNP transistor are all connected to the positive electrode of the power supply, the collector of the seventh PNP transistor is connected to the first end of the twenty-sixth resistor, the second end of the twenty-sixth resistor is respectively connected to the first end of the twenty-seventh resistor and the base of the eleventh NPN transistor, the collector of the eleventh NPN transistor is respectively connected to the second end of the eighteenth resistor and the first end of the twenty-first resistor, and the second end of the twenty-first resistor serves as the forward output end of the forward instruction processing module;The anode of the fifteenth diode is the input end of the reversal instruction processing module, the cathode of the fifteenth diode is connected to the first end of the thirty-first resistor, the second end of the thirty-first resistor is connected to the base of the twelfth NPN transistor, the collector of the twelfth NPN transistor is respectively connected to the first end of the forty-sixth resistor and the first end of the thirty-second resistor, the second end of the forty-sixth resistor is respectively connected to the cathode of the thirteenth voltage-stabilizing diode, the first end of the twenty-eighth resistor and the first end of the forty-seventh resistor, the emitter of the twelfth NPN transistor is respectively connected to the emitter of the thirteenth NPN transistor and the first end of the thirty-fifth resistor, the base of the thirteenth NPN transistor is connected to the second end of the thirty-second resistor, the collector of the thirteenth NPN transistor is respectively connected to the second end of the forty-seventh resistor and the first end of the thirty-third resistor The first end of the thirty-third resistor is connected, the second end of the thirty-third resistor is connected to the base of the fourteenth PNP transistor, the collector of the fourteenth PNP transistor is connected to the first end of the thirty-fourth resistor, the second end of the thirty-fourth resistor is respectively connected to the first end of the thirty-sixth resistor and the base of the sixteenth NPN transistor, the collector of the sixteenth NPN transistor is respectively connected to the second end of the twenty-ninth resistor and the first end of the thirty-seventh resistor, and the second end of the thirty-seventh resistor serves as the inversion output end of the inversion instruction processing module; the anode of the eighteenth voltage-stabilizing diode, the second end of the twenty-fifth resistor, the second end of the twenty-seventh resistor, the emitter of the eleventh NPN transistor, the anode of the thirteenth voltage-stabilizing diode, the second end of the thirty-fifth resistor, the second end of the thirty-sixth resistor and the emitter of the sixteenth NPN transistor are all connected to the negative electrode of the power supply. ;

[0011] Furthermore, an eleventh resistor and a second capacitor are connected in parallel between the cathode of the eleventh diode and the cathode of the power supply; and a thirtieth resistor and a fourth capacitor are connected in parallel between the cathode of the fifteenth diode and the cathode of the power supply.

[0012] Preferably, the forward drive module includes a first resistor, a third resistor, a fifth resistor, a seventh resistor, a ninth resistor, a thirteenth resistor, a third NPN transistor, a first photoelectric coupler, a first P-type field effect transistor, a fifth N-type field effect transistor, a first voltage regulator diode, a fifth voltage regulator diode, a third diode and a sixth diode, and the reverse drive module includes a second resistor, a fourth resistor, a sixth resistor, an eighth resistor, a tenth resistor, a fourteenth resistor, a fourth NPN transistor, a second photoelectric coupler, a second P-type field effect transistor, a sixth N-type field effect transistor, a second voltage regulator diode, an eighth voltage regulator diode, a fourth diode and a seventh diode, and the first end of the ninth resistor As the input end of the forward drive module, the second end of the ninth resistor is connected to the base of the third NPN transistor, the collector of the third NPN transistor is connected to the negative electrode of the input end of the first photoelectric coupler, the positive electrode of the input end of the first photoelectric coupler is connected to the first end of the third resistor, the positive electrode of the output end of the first photoelectric coupler is connected to the first end of the fifth resistor, the second end of the fifth resistor is respectively connected to the first end of the first resistor, the positive electrode of the first voltage regulator diode and the gate of the first P-type field effect transistor, the negative electrode of the output end of the first photoelectric coupler is connected to the first end of the seventh resistor, and the second end of the seventh resistor is connected to the positive electrode of the output end of the first photoelectric coupler. The first end of the tenth resistor is used as the input end of the inversion drive module, the second end of the tenth resistor is connected to the base of the fourth NPN transistor, the collector of the fourth NPN transistor is connected to the negative electrode of the input end of the second photoelectric coupler, the positive electrode of the input end of the second photoelectric coupler is connected to the first end of the fourth resistor, and the positive electrode of the input end of the fourth resistor is connected to the first end of the fourth resistor. The positive electrode of the output end of the second photocoupler is connected to the first end of the sixth resistor, the second end of the sixth resistor is respectively connected to the first end of the second resistor, the positive electrode of the second voltage-stabilizing diode and the gate of the second P-type field effect transistor, the negative electrode of the output end of the second photocoupler is connected to the first end of the eighth resistor, the second end of the eighth resistor is respectively connected to the first end of the fourteenth resistor, the negative electrode of the eighth voltage-stabilizing diode and the gate of the fifth N-type field effect transistor, the drain of the second P-type field effect transistor, the drain of the sixth N-type field effect transistor, the positive electrode of the fourth diode and the negative electrode of the seventh diode are all connected to the second end of the DC motor;The second end of the third resistor, the cathode of the first voltage-stabilizing diode, the second end of the first resistor, the source of the first P-type field effect transistor, the cathode of the third diode, the cathode of the fourth diode, the source of the second P-type field effect transistor, the second end of the second resistor, the cathode of the second voltage-stabilizing diode and the second end of the fourth resistor are all connected to the positive electrode of the power supply, and the emitter of the third NPN transistor, the anode of the fifth voltage-stabilizing diode, the second end of the thirteenth resistor, the source of the fifth N-type field effect transistor, the anode of the sixth diode, the anode of the seventh diode, the source of the sixth N-type field effect transistor, the second end of the fourteenth resistor, the anode of the eighth voltage-stabilizing diode and the emitter of the fourth NPN transistor are all connected to the negative electrode of the power supply. The first and second ends of the above-mentioned DC motor are also called A end and B end. ;

[0013] The beneficial effects of the present invention are:

[0014] The present invention increases an instruction interlocking module and utilizes an interlocking structure between two NPN transistors, so that at most only one of the forward drive instruction signal and the reverse drive instruction signal output to the forward drive module and the reverse drive module at the same time is valid. When the forward instruction and the reverse instruction are given simultaneously due to an operation error, the instruction interlocking module can force one of the instructions to be invalid, thereby avoiding circuit damage and improving circuit reliability. The forward instruction and the reverse instruction are processed by using a forward instruction processing module and a reverse instruction processing module respectively composed of four transistors to realize a dual threshold switch control function. When the voltage of the forward instruction or the reverse instruction is greater than a high-level threshold voltage, the instruction changes from invalid to valid. When the voltage of the forward instruction or the reverse instruction is less than a low-level threshold voltage, the instruction changes from valid to invalid. In this way, the stability of the control of the forward instruction and the reverse instruction can be guaranteed, and the problem of circuit damage caused by frequent start and stop of a DC motor due to instruction voltage fluctuation can be avoided. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is the overall block diagram of the H-bridge mutually exclusive driving circuit of the DC motor of the present invention;

[0016] Figure 2 It is a circuit diagram of a forward command processing module, a reverse command processing module and a command interlocking module of the H-bridge mutually exclusive driving circuit of a DC motor according to the present invention;

[0017] Figure 3 It is a circuit diagram of a forward drive module and a reverse drive module of the H-bridge mutually exclusive drive circuit of a DC motor described in the present invention. DETAILED DESCRIPTION

[0018] The present invention will be further described below in conjunction with the accompanying drawings:

[0019] like Figure 1 and Figure 2 As shown, the H-bridge mutually exclusive driving circuit of the DC motor of the present invention comprises a forward driving module receiving a forward instruction, a reverse driving module receiving a reverse instruction, a forward instruction processing module and a reverse instruction processing module, the input end of the forward instruction processing module inputs the forward instruction, the forward output end of the forward instruction processing module is connected to the input end of the forward driving module, the input end of the reverse instruction processing module inputs the reverse instruction, and the reverse output end of the reverse instruction processing module is connected to the input end of the reverse driving module; the instruction interlocking module comprises a twenty-second electric The twenty-second resistor R22, the twenty-third resistor R23, the thirty-eighth resistor R38, the thirty-ninth resistor R39, the ninth diode D9, the tenth diode D10, the twelfth diode D12, the fourteenth diode D14, the sixteenth diode D16, the seventeenth diode D17, the eighth NPN transistor Q8 and the fifteenth NPN transistor Q15, the first end of the twenty-second resistor R22 is connected to the anode of the twelfth diode D12 and serves as the forward input end of the instruction interlock module, the second end of the twenty-second resistor R22 is connected to the anode of the ninth diode D9, and the ninth diode D14 is connected to the positive pole of the ninth diode D14. The cathode of the transistor D9 is respectively connected to the base of the eighth NPN transistor Q8 and the first end of the twenty-third resistor R23, the collector of the eighth NPN transistor Q8 is connected to the cathode of the tenth diode D10, the cathode of the twelfth diode D12 is connected to the anode of the fourteenth diode D14 and serves as the forward drive output end of the instruction interlocking module, the first end of the thirty-eighth resistor R38 is connected to the anode of the seventeenth diode D17 and serves as the inverting input end of the instruction interlocking module, the second end of the thirty-eighth resistor R38 is connected to the anode of the sixteenth diode D16, and the sixteenth The cathode of the diode D16 is respectively connected to the base of the fifteenth NPN transistor Q15 and the first end of the thirty-ninth resistor R39, the collector of the fifteenth NPN transistor Q15 is connected to the cathode of the fourteenth diode D14, the cathode of the seventeenth diode D17 is connected to the anode of the tenth diode D10 and serves as the reverse drive output end of the instruction interlocking module, the second end of the twenty-third resistor R23, the emitter of the eighth NPN transistor Q8, the second end of the thirty-ninth resistor R39 and the emitter of the fifteenth NPN transistor Q15 are all connected to the negative electrode GND of the power supply.

[0020] like Figure 2As shown, during normal operation, the forward input terminal and the reverse input terminal of the instruction interlock module have only one signal, and the corresponding forward drive output terminal and the reverse drive output terminal only output one output signal, because the NPN transistor without signal input is cut off and the output signal will not be pulled low, so the corresponding forward drive output signal and the reverse drive output signal can be output normally; if the forward instruction and the reverse instruction are given at the same time due to an operational error, the forward input terminal and the reverse input terminal of the instruction interlock module have signals. At this time, the forward drive output terminal and the reverse drive output terminal can only have one output signal, because: after any one of the eighth NPN transistor Q8 and the fifteenth NPN transistor Q15 is turned on, it will inevitably cause the base voltage and output signal voltage of the other NPN transistor to be extremely low, thereby causing the NPN transistor to be cut off, and will not pull down the voltage of the output signal corresponding to the turned-on NPN transistor, so that it can output the signal normally.

[0021] The present invention also discloses the following more specific optimization circuits:

[0022] like Figure 2 As shown, a first capacitor C1 is connected between the first end of the twenty-second resistor R22 and the second end of the twenty-third resistor R23, and a third capacitor C3 is connected between the first end of the thirty-eighth resistor R38 and the second end of the thirty-ninth resistor R39.

[0023] like Figure 2As shown, the forward instruction processing module includes an eleventh diode D11, an eighteenth voltage stabilizing diode D18, a fifteenth resistor R15, a sixteenth resistor R16, a seventeenth resistor R17, an eighteenth resistor R18, a nineteenth resistor R19, a twentieth resistor R20, a twenty-first resistor R21, a twenty-fourth resistor R24, a twenty-fifth resistor R25, a twenty-sixth resistor R26, a twenty-seventh resistor R27, a seventh PNP transistor Q7, a ninth NPN transistor Q9, a tenth NPN transistor Q10 and an eleventh NPN transistor Q11, and the reverse instruction processing module includes a fifteenth diode D15, a thirteenth voltage stabilizing diode D13, a forty-sixth resistor R46, a forty-seventh resistor R47, a twenty-eighth resistor R21, a twenty-fourth resistor R24, a twenty-fifth resistor R25, a twenty-sixth resistor R26, a twenty-seventh resistor R27, a seventh PNP transistor Q7, a ninth NPN transistor Q9, a tenth NPN transistor Q10 and an eleventh NPN transistor Q11. a first terminal of the second resistor R24 ​​connected to the base of the ninth NPN transistor Q9, a second terminal of the second resistor R24 ​​connected to the second terminal of the second resistor R24, a third terminal of the second resistor R24 ​​connected to the second terminal of the second resistor R24, a fourth terminal of the second resistor R24 ​​connected to the second terminal of the second resistor R24, a fifth ... The first end of the resistor R16 is connected to the first end of the nineteenth resistor R19, the second end of the sixteenth resistor R16 is respectively connected to the cathode of the eighteenth voltage zener diode D18, the first end of the fifteenth resistor R15 and the first end of the seventeenth resistor R17, the emitter of the ninth NPN transistor Q9 is respectively connected to the emitter of the tenth NPN transistor Q10 and the first end of the twenty-fifth resistor R25, the base of the tenth NPN transistor Q10 is connected to the second end of the nineteenth resistor R19, the collector of the tenth NPN transistor Q10 is respectively connected to the second end of the seventeenth resistor R17 and the first end of the twentieth resistor R20, the second end of the twentieth resistor R20 is connected to the base of the seventh PNP transistor Q7, and the seventh PNP transistor Q7 is connected to the base of the seventh PNP transistor Q7. The emitter of the first PNP transistor Q14, the second end of the fifteenth resistor R15, the first end of the eighteenth resistor R18, the first end of the twenty-eighth resistor R28, the first end of the twenty-ninth resistor R29 and the emitter of the fourteenth PNP transistor Q14 are all connected to the positive power supply VCC, the collector of the seventh PNP transistor Q7 is connected to the first end of the twenty-sixth resistor R26, the second end of the twenty-sixth resistor R26 is respectively connected to the first end of the twenty-seventh resistor R27 and the base of the eleventh NPN transistor Q11, the collector of the eleventh NPN transistor Q11 is respectively connected to the second end of the eighteenth resistor R18 and the first end of the twenty-first resistor R21, and the second end of the twenty-first resistor R21 serves as the forward output end of the forward instruction processing module;The anode of the fifteenth diode D15 is the input end of the reversal instruction processing module, the cathode of the fifteenth diode D15 is connected to the first end of the thirty-first resistor R31, the second end of the thirty-first resistor R31 is connected to the base of the twelfth NPN transistor Q12, the collector of the twelfth NPN transistor Q12 is respectively connected to the first end of the forty-sixth resistor R46 and the first end of the thirty-second resistor R32, the second end of the forty-sixth resistor R46 is respectively connected to the cathode of the thirteenth voltage-stabilizing diode D13, the first end of the twenty-eighth resistor R28 and the first end of the forty-seventh resistor R47, the emitter of the twelfth NPN transistor Q12 is respectively connected to the emitter of the thirteenth NPN transistor Q13 and the first end of the thirty-fifth resistor R35, the base of the thirteenth NPN transistor Q13 is connected to the second end of the thirty-second resistor R32, the collector of the thirteenth NPN transistor Q13 is respectively connected to the second end of the forty-seventh resistor R47 and the first end of the thirty-third resistor R33. The first end of the 33rd resistor R33 is connected to the base of the 14th PNP transistor Q14, the collector of the 14th PNP transistor Q14 is connected to the first end of the 34th resistor R34, the second end of the 34th resistor R34 is respectively connected to the first end of the 36th resistor R36 and the base of the 16th NPN transistor Q16, the collector of the 16th NPN transistor Q16 is respectively connected to the second end of the 29th resistor R29 and the first end of the 37th resistor R37, and the second end of the 37th resistor R37 serves as the inversion output end of the inversion instruction processing module; the anode of the 18th voltage stabilizing diode D18, the second end of the 25th resistor R25, the second end of the 27th resistor R27, the emitter of the 11th NPN transistor Q11, the anode of the 13th voltage stabilizing diode D13, the second end of the 35th resistor R35, the second end of the 36th resistor R36 and the emitter of the 16th NPN transistor Q16 are all connected to the negative power supply GND. ;

[0024] like Figure 2 As shown, the eleventh resistor R11 and the second capacitor C2 are connected in parallel between the cathode of the eleventh diode D11 and the negative power supply GND; the thirtieth resistor R30 and the fourth capacitor C4 are connected in parallel between the cathode of the fifteenth diode D15 and the negative power supply GND.

[0025] The forward command and the reverse command are processed by using a forward command processing module and a reverse command processing module respectively composed of four triodes to realize a dual threshold switch control function. When the voltage of the forward command or the reverse command is greater than the high-level threshold voltage, the command changes from invalid to valid. When the voltage of the forward command or the reverse command is less than the low-level threshold voltage, the command changes from valid to invalid. In this way, the stability of the control of the forward command and the reverse command can be ensured, and the circuit damage problem caused by the frequent start and stop of the DC motor M due to the fluctuation of the command voltage is avoided.

[0026] like Figure 2 As shown, taking the forward command processing module as an example, the dual threshold switch control principle is as follows:

[0027] When the dual threshold switch is in the off state, the ninth NPN transistor Q9 is turned off, the tenth NPN transistor Q10, the seventh PNP transistor Q7, and the eleventh NPN transistor Q11 are all turned on, and the positive output is 0.7V; because the tenth NPN transistor Q10 is turned on, the voltage at the first end of the twenty-fifth resistor R25 is recorded as U 25 (High) = (VCC-0.7)*R 25 / (R 17 +R 25 ), where R 25 and R 17 Respectively represent the resistance values ​​of the twenty-fifth resistor R25 and the seventeenth resistor R17. To make the double threshold switch become closed, the forward command voltage needs to be increased. When the forward command voltage>U 25 When (high) +0.7, the ninth NPN transistor Q9 is turned on, and the tenth NPN transistor Q10 is turned off, so that the seventh PNP transistor Q7 and the eleventh NPN transistor Q11 are both turned off, the double threshold switch becomes closed, and the positive output is the power supply voltage VCC;

[0028] When the double threshold switch is in the closed state, the ninth NPN transistor Q9 is turned on. 25 (Low) = (VCC-0.7)*R 25 / (R 16 +R 25 ), where R 25 and R 16 Represent the resistance values ​​of the twenty-fifth resistor R25 and the sixteenth resistor R16 respectively. To turn the double threshold switch into the off state, the forward command voltage needs to be reduced. 25 When (low) +0.7, the ninth NPN transistor Q9 is turned off, and the eleventh NPN transistor Q10 is turned on, so that the seventh PNP transistor Q7 and the eleventh NPN transistor Q11 are both turned on, the dual threshold switch becomes off, and the forward output is 0.7V.

[0029] Set the parameters of R16, R17, and R25 so that U 25 (High)>U 25 (Low). Set high threshold level = U 25 (High) +0.7, Low threshold level = U 25 (Low) +0.7, a double threshold switch can be realized.

[0030] By analogy, the dual threshold switch control of the reversal instruction processing module can be realized.​

[0031] like Figure 3As shown, the forward drive module includes a first resistor R1, a third resistor R3, a fifth resistor R5, a seventh resistor R7, a ninth resistor R9, a thirteenth resistor R13, a third NPN transistor Q3, a first photoelectric coupler O1, a first P-type field effect transistor Q1, a fifth N-type field effect transistor Q5, a first voltage regulator diode D1, a fifth voltage regulator diode D5, a third diode D3 and a sixth diode D6, and the reverse drive module includes a second resistor R2, a fourth resistor R4, a sixth resistor R6, an eighth resistor R8, a tenth resistor R10, a fourteenth resistor R14, a fourth NPN transistor Q4, a second photoelectric coupler O2, a second P-type field effect transistor Q2, a sixth N-type field effect transistor Q6, a second voltage regulator diode D1, a fifth voltage regulator diode D5, a third diode D3 and a sixth diode D6. The first end of the ninth resistor R9 is connected to the base of the third NPN transistor Q3, the collector of the third NPN transistor Q3 is connected to the negative electrode of the input end of the first photoelectric coupler O1, the positive electrode of the input end of the first photoelectric coupler O1 is connected to the first end of the third resistor R3, the positive electrode of the output end of the first photoelectric coupler O1 is connected to the first end of the fifth resistor R5, the second end of the fifth resistor R5 is respectively connected to the first end of the first resistor R1, the positive electrode of the first voltage stabilizing diode D1 and the gate of the first P-type field effect transistor Q1, and the output end of the first photoelectric coupler O1 is connected to the positive electrode of the output end of the first photoelectric coupler O1. The negative electrode of the tenth resistor R10 is connected to the first end of the seventh resistor R7, the second end of the seventh resistor R7 is respectively connected to the first end of the thirteenth resistor R13, the negative electrode of the fifth voltage-stabilizing diode D5 and the gate of the sixth N-type field effect transistor Q6, the drain of the first P-type field effect transistor Q1, the drain of the fifth N-type field effect transistor Q5, the positive electrode of the third diode D3 and the negative electrode of the sixth diode D6 are all connected to the first end of the DC motor M; the first end of the tenth resistor R10 serves as the input end of the inversion drive module, the second end of the tenth resistor R10 is connected to the base of the fourth NPN transistor Q4, the collector of the fourth NPN transistor Q4 is connected to the negative electrode of the input end of the second photoelectric coupler O2, the positive electrode of the input end of the second photoelectric coupler O2 is connected to the fourth The first end of the resistor R4 is connected, the positive electrode of the output end of the second photoelectric coupler O2 is connected to the first end of the sixth resistor R6, the second end of the sixth resistor R6 is respectively connected to the first end of the second resistor R2, the positive electrode of the second voltage-stabilizing diode D2 and the gate of the second P-type field effect transistor Q2, the negative electrode of the output end of the second photoelectric coupler O2 is connected to the first end of the eighth resistor R8, the second end of the eighth resistor R8 is respectively connected to the first end of the fourteenth resistor R14, the negative electrode of the eighth voltage-stabilizing diode D8 and the gate of the fifth N-type field effect transistor Q5, the drain of the second P-type field effect transistor Q2, the drain of the sixth N-type field effect transistor Q6, the positive electrode of the fourth diode D4 and the negative electrode of the seventh diode D7 are all connected to the second end of the DC motor M;The second end of the third resistor R3, the cathode of the first voltage-stabilizing diode D1, the second end of the first resistor R1, the source of the first P-type field effect transistor Q1, the cathode of the third diode D3, the cathode of the fourth diode D4, the source of the second P-type field effect transistor Q2, the second end of the second resistor R2, the cathode of the second voltage-stabilizing diode D2 and the second end of the fourth resistor R4 are all connected to the positive power supply electrode VCC, the emitter of the third NPN transistor Q3, the anode of the fifth voltage-stabilizing diode D5, the second end of the thirteenth resistor R13, the source of the fifth N-type field effect transistor Q5, the anode of the sixth diode D6, the anode of the seventh diode D7, the source of the sixth N-type field effect transistor Q6, the second end of the fourteenth resistor R14, the anode of the eighth voltage-stabilizing diode D8 and the emitter of the fourth NPN transistor Q4 are all connected to the negative power supply electrode GND. The gate, drain and source are represented by G, D and S respectively in the figure. ;

[0032] illustrate: Figure 1 S1-S4 in the figure represent four MOS tubes or power transistors, and in the present embodiment, S1-S4 respectively adopt the first P-type field effect tube Q1, the fifth N-type field effect tube Q5, the second P-type field effect tube Q2 and the sixth N-type field effect tube Q6.

[0033] The above embodiments are only preferred embodiments of the present invention and are not limitations of the technical solutions of the present invention. Any technical solution that can be implemented on the basis of the above embodiments without creative work should be deemed to fall within the scope of protection of the patent of the present invention.

Claims

1. A DC motor H-bridge mutually exclusive drive circuit, comprising a forward drive module receiving a forward command and a reverse drive module receiving a reverse command, characterized in that: The invention also includes a forward instruction processing module, a reverse instruction processing module and an instruction interlocking module, wherein the input end of the forward instruction processing module inputs the forward instruction, the forward output end of the forward instruction processing module is connected to the forward input end of the instruction interlocking module, the forward drive output end of the instruction interlocking module is connected to the input end of the forward drive module, the input end of the reverse instruction processing module inputs the reverse instruction, the reverse output end of the reverse instruction processing module is connected to the reverse input end of the instruction interlocking module, and the reverse drive output end of the instruction interlocking module is connected to the input end of the reverse drive module; the instruction interlocking module includes a twenty-second resistor, a twenty-third resistor, a thirty-eighth resistor, a thirty-ninth resistor, a ninth diode, a tenth diode, a twelfth diode, a fourteenth diode, a sixteenth diode, a seventeenth diode, an eighth NPN transistor and a fifteenth NPN transistor, the first end of the twenty-second resistor is connected to the positive electrode of the twelfth diode and serves as the forward input end of the instruction interlocking module, the second end of the twenty-second resistor is connected to the positive electrode of the ninth diode The cathode of the ninth diode is respectively connected to the base of the eighth NPN transistor and the first end of the twenty-third resistor, the collector of the eighth NPN transistor is connected to the cathode of the tenth diode, the cathode of the twelfth diode is connected to the anode of the fourteenth diode and serves as the forward drive output end of the instruction interlock module, the first end of the thirty-eighth resistor is connected to the anode of the seventeenth diode and serves as the reverse input end of the instruction interlock module, the second end of the thirty-eighth resistor is connected to the anode of the sixteenth diode, the cathode of the sixteenth diode is respectively connected to the base of the fifteenth NPN transistor and the first end of the thirty-ninth resistor, the collector of the fifteenth NPN transistor is connected to the cathode of the fourteenth diode, the cathode of the seventeenth diode is connected to the anode of the tenth diode and serves as the reverse drive output end of the instruction interlock module, and the second end of the twenty-third resistor, the emitter of the eighth NPN transistor, the second end of the thirty-ninth resistor and the emitter of the fifteenth NPN transistor are all connected to the negative electrode of the power supply.

2. The DC motor H-bridge mutually exclusive driving circuit according to claim 1, characterized in that: A first capacitor is connected between the first end of the twenty-second resistor and the second end of the twenty-third resistor, and a third capacitor is connected between the first end of the thirty-eighth resistor and the second end of the thirty-ninth resistor.

3. The DC motor H-bridge mutually exclusive drive circuit according to claim 1 or 2, characterized in that: The forward drive module includes a first resistor, a third resistor, a fifth resistor, a seventh resistor, a ninth resistor, a thirteenth resistor, a third NPN transistor, a first photoelectric coupler, a first P-type field effect transistor, a fifth N-type field effect transistor, a first voltage regulator diode, a fifth voltage regulator diode, a third diode and a sixth diode, and the reverse drive module includes a second resistor, a fourth resistor, a sixth resistor, an eighth resistor, a tenth resistor, a fourteenth resistor, a fourth NPN transistor, a second photoelectric coupler, a second P-type field effect transistor, a sixth N-type field effect transistor, a second voltage regulator diode, an eighth voltage regulator diode, a fourth diode and a seventh diode, and the first end of the ninth resistor is used as the The input end of the forward drive module, the second end of the ninth resistor is connected to the base of the third NPN transistor, the collector of the third NPN transistor is connected to the negative electrode of the input end of the first photoelectric coupler, the positive electrode of the input end of the first photoelectric coupler is connected to the first end of the third resistor, the positive electrode of the output end of the first photoelectric coupler is connected to the first end of the fifth resistor, the second end of the fifth resistor is respectively connected to the first end of the first resistor, the positive electrode of the first voltage regulator diode and the gate of the first P-type field effect transistor, the negative electrode of the output end of the first photoelectric coupler is connected to the first end of the seventh resistor, and the second end of the seventh resistor is respectively connected to The first end of the thirteenth resistor, the cathode of the fifth voltage-stabilizing diode and the gate of the sixth N-type field effect transistor are connected, and the drain of the first P-type field effect transistor, the drain of the fifth N-type field effect transistor, the anode of the third diode and the cathode of the sixth diode are all connected to the first end of the DC motor; the first end of the tenth resistor serves as the input end of the inversion drive module, the second end of the tenth resistor is connected to the base of the fourth NPN transistor, the collector of the fourth NPN transistor is connected to the cathode of the input end of the second photocoupler, the anode of the input end of the second photocoupler is connected to the first end of the fourth resistor, and the cathode of the second photocoupler is connected to the cathode of the input end of the fourth resistor. The positive electrode of the output end of the electric coupler is connected to the first end of the sixth resistor, the second end of the sixth resistor is respectively connected to the first end of the second resistor, the positive electrode of the second voltage-stabilizing diode and the gate of the second P-type field effect transistor, the negative electrode of the output end of the second photoelectric coupler is connected to the first end of the eighth resistor, the second end of the eighth resistor is respectively connected to the first end of the fourteenth resistor, the negative electrode of the eighth voltage-stabilizing diode and the gate of the fifth N-type field effect transistor, the drain of the second P-type field effect transistor, the drain of the sixth N-type field effect transistor, the positive electrode of the fourth diode and the negative electrode of the seventh diode are all connected to the second end of the DC motor;The second end of the third resistor, the cathode of the first voltage-stabilizing diode, the second end of the first resistor, the source of the first P-type field effect transistor, the cathode of the third diode, the cathode of the fourth diode, the source of the second P-type field effect transistor, the second end of the second resistor, the cathode of the second voltage-stabilizing diode and the second end of the fourth resistor are all connected to the positive electrode of the power supply, and the emitter of the third NPN transistor, the anode of the fifth voltage-stabilizing diode, the second end of the thirteenth resistor, the source of the fifth N-type field effect transistor, the anode of the sixth diode, the anode of the seventh diode, the source of the sixth N-type field effect transistor, the second end of the fourteenth resistor, the anode of the eighth voltage-stabilizing diode and the emitter of the fourth NPN transistor are all connected to the negative electrode of the power supply. ;

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