A stepper motor drive circuit

Abstract

This utility model relates to the field of motor drive circuit technology, and more particularly to a drive circuit for a stepper motor. The stepper motor drive circuit includes a signal preprocessing module and a signal conversion module. The signal preprocessing module includes a transistor, and the signal conversion module includes a field-effect transistor (FET). The transistor amplifies the phase control signal into a boost control signal for the motor, and the FET converts the boost control signal into the drive signal for the stepper motor. This design ensures the drive circuit is simple, versatile, and adaptable to various stepper motors.

Description

Technical Field

[0001] This utility model belongs to the field of motor drive circuit technology, and particularly relates to a drive circuit for a stepper motor. Background Technology

[0002] Currently, stepper motors are typically driven using motor driver chips. While these chips offer high integration, their control voltage and current are limited. When different stepper motor models are used, there is a risk of overcurrent and overload damage to the driver chip or circuit board. Therefore, motor driver chips lack versatility and are not suitable for various stepper motors. Thus, achieving a simple, versatile driver circuit that adapts to multiple stepper motors has become a pressing issue. Utility Model Content

[0003] In view of this, the present invention aims to provide a stepper motor drive circuit that ensures the simplicity and versatility of the drive circuit and adaptability to various stepper motors.

[0004] To achieve the above objectives, the technical solution of this utility model is implemented as follows:

[0005] This utility model provides a driving circuit for a stepper motor, including a signal preprocessing module and a signal conversion module. The signal preprocessing module includes a transistor, and the signal conversion module includes a field-effect transistor. The transistor boosts and amplifies the phase control signal into a motor boost control signal, and the field-effect transistor converts the motor boost control signal into the driving signal for the stepper motor.

[0006] Furthermore, the signal preprocessing module includes a transistor, and the signal conversion module includes a field-effect transistor. The transistor boosts and amplifies the phase control signal into the motor boost control signal, and the field-effect transistor converts the motor boost control signal into the drive signal of the stepper motor.

[0007] Furthermore, the transistor is an NPN transistor (A1), and the signal preprocessing module also includes two resistors (R1, R2). The phase control signal is input to the base of the transistor (A1), the operating voltage of the transistor (A1) is connected to the collector of the transistor (A1) via resistor (R1), the emitter of the transistor (A1) is grounded, one end of resistor (R2) is connected between resistor (R1) and the collector of the transistor (A1), and the other end of resistor (R2) is grounded. The electrode boost control signal is output from the collector of the transistor (A1) to the signal conversion module.

[0008] Furthermore, the signal preprocessing module also includes a resistor (R3) connected to the base of the transistor (A1), and the phase control signal is input to the base of the transistor (A1) via the resistor (R3).

[0009] Furthermore, when the stepper motor is working, the operating voltage of the stepper motor provides a power supply voltage to the drive circuit.

[0010] Furthermore, the driving circuit also includes a transistor voltage divider circuit, through which the operating voltage of the stepper motor is divided to produce the operating voltage of the transistor (A1).

[0011] Furthermore, the transistor voltage divider circuit includes two resistors (R4, R5). The operating voltage of the stepper motor is connected to one end of the series connection of resistors (R4 and R5), and the other end of the series connection of resistors (R4 and R5) is grounded. The operating voltage of the transistor is output from between resistors (R4 and R5).

[0012] Furthermore, the field-effect transistor is an N-type field-effect transistor (A2). The motor boost control signal is input to the gate of the N-type field-effect transistor (A2). The source of the N-type field-effect transistor (A2) is connected to the gate, and the drain of the N-type field-effect transistor (A2) is connected to the start coil of the stepper motor. The drive signal drives the stepper motor from the drain of the N-type field-effect transistor (A2).

[0013] Furthermore, the drive circuit also includes a voltage regulator module, which is disposed between the operating voltage of the stepper motor and the start coil of the stepper motor.

[0014] Furthermore, the voltage regulator module includes a capacitor (C1), the operating voltage of the stepper motor is connected to one end of the capacitor, and the other end of the capacitor is connected to both the start coil of the stepper motor and the drain of the N-type field-effect transistor (A2).

[0015] Furthermore, the voltage regulator module also includes a diode (V1), which is connected in parallel with the capacitor (C1) between the operating voltage of the stepper motor and the starting coil of the stepper motor. The negative terminal of the diode (V1) is connected to the operating voltage of the stepper motor, and the positive terminal of the diode (V1) is connected to both the starting coil of the stepper motor and the drain of the N-type field-effect transistor (A2).

[0016] Compared with existing technologies, this invention achieves the following beneficial effects: The stepper motor drive circuit provided by this invention includes a signal preprocessing module and a signal conversion module. The signal preprocessing module includes a transistor, and the signal conversion module includes a field-effect transistor (FET). The transistor boosts and amplifies the phase control signal into a motor boost control signal, and the FET converts the motor boost control signal into a stepper motor drive signal. After being amplified by the transistor, the stepper motor's phase control signal drives the FET to output a pulse signal that the stepper motor can recognize, i.e., the stepper motor drive signal. This stepper motor drive circuit has a simple structure, requiring only one transistor and one FET, and is highly versatile, applicable to the drive control of various stepper motors. Attached Figure Description

[0017] The accompanying drawings, which form part of this utility model, are used to provide a further understanding of the utility model. The illustrative embodiments of the utility model and their descriptions are used to explain the utility model and do not constitute an undue limitation of the utility model. In the drawings:

[0018] Figure 1 A schematic diagram of a driving circuit according to an embodiment of this utility model is provided;

[0019] Figure 2 A schematic diagram of a driving circuit for another embodiment of this utility model is provided;

[0020] Figure 3 A schematic diagram of a transistor voltage divider circuit in a driving circuit according to another embodiment of this utility model.

[0021] Explanation of reference numerals in the attached figures:

[0022] 10. Drive circuit; 100. Signal preprocessing module; 110. Signal conversion module. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only for explaining the present utility model and do not constitute a limitation thereof. Similar elements in different embodiments are referred to by associated similar element reference numerals. In the following embodiments, many details are described to enable a better understanding of the present utility model. However, those skilled in the art will readily recognize that some features may be omitted in different situations, or may be replaced by other elements, materials, or methods. In some cases, some operations related to the present utility model are not shown or described in the specification. This is to avoid obscuring the core parts of the present utility model with excessive description. For those skilled in the art, detailed description of these related operations is not necessary; they can fully understand the related operations based on the description in the specification and general technical knowledge in the art.

[0024] It should be noted that, unless otherwise specified, the embodiments and features described in this utility model can be combined to form various implementation methods. Furthermore, the order of the steps or actions in the method description can be changed or adjusted in a manner readily apparent to those skilled in the art. Therefore, the various orders in the specification and drawings are merely for the clear description of a particular embodiment and do not imply a mandatory order, unless otherwise stated that a particular order must be followed.

[0025] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0026] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0027] like Figure 1As shown, the stepper motor drive circuit 10 provided in this embodiment includes a signal preprocessing module 100 and a signal conversion module 110. The signal preprocessing module 100 includes a transistor, and the signal conversion module 110 includes a field-effect transistor. The transistor boosts and amplifies the phase control signal into a motor boost control signal, and the field-effect transistor converts the motor boost control signal into a stepper motor drive signal. The signal preprocessing module 100 in this drive circuit 10 includes only one transistor, and the signal conversion module 110 includes only one field-effect transistor. The drive circuit has a simple structure and low cost.

[0028] The driver circuit 10 converts the stepper motor's phase control signal into a stepper motor drive signal. For different stepper motors, the corresponding stepper motor's phase control signal can be input to the driver circuit to drive the stepper motor, achieving strong versatility and adaptability to various stepper motors. The stepper motor's phase control signal, after being output by the MCU, is boosted and amplified by a transistor to drive an N-type field-effect transistor (MOSFET) to output the stepper motor drive signal, thus providing a responsive drive signal for the stepper motor.

[0029] Furthermore, such as Figure 2 As shown, in the stepper motor drive circuit 10 provided in this embodiment of the present invention, the transistor is an NPN transistor A1. The signal preprocessing module 100 also includes two resistors R1 and R2. The phase control signal is input to the base of transistor A1. The operating voltage of transistor A1 is connected to the collector of transistor A1 via resistor R1. The emitter of transistor A1 is grounded. One end of resistor R2 is connected between resistor R1 and the collector of transistor A1, and the other end of resistor R2 is grounded. The motor boost control signal Motor_Control_Plus is output from the collector of transistor A1 to the signal conversion module 110. The phase control signal Motor_Control is divided by resistors R1 and R2 in series to generate the motor boost control signal Motor_Control_Plus.

[0030] like Figure 2 The diagram shown is a schematic of one embodiment of the stepper motor drive circuit provided by this utility model. Motor_Control is the phase control signal of the stepper motor output by an MCU. The MCU includes, but is not limited to, microcontrollers such as single-chip microcomputers, DSPs, and FPGAs. Depending on the selection of the microcontroller, the operating voltage range of Motor_Control is generally between 1.2V and 5.5V.

[0031] Furthermore, such as Figure 2In the schematic diagram of the stepper motor drive circuit embodiment shown, the signal preprocessing module 100 further includes a resistor R3, which is connected to the base of transistor A1. The phase control signal is input to the base of transistor A1 via resistor R3. The phase control signal Motor_Control is connected to the base (BASE) pin of NPN transistor A1 via resistor R3. The operating voltage VControl of transistor A1 is connected to the collector (Collector) pin of NPN transistor A1 via resistor R1. The power ground GND is connected to the emitter (Emitter) pin of NPN transistor A1. Furthermore, in the stepper motor drive circuit provided by this embodiment, when the stepper motor is working, the operating voltage of the stepper motor provides the power supply voltage to the drive circuit. This drive circuit only starts working when the stepper motor is working, which can significantly reduce the additional power consumption of the drive circuit.

[0032] Furthermore, in the stepper motor drive circuit provided in this embodiment of the invention, the drive circuit also includes a transistor voltage divider circuit, and the operating voltage of the stepper motor is divided by the transistor voltage divider circuit to obtain the operating voltage of transistor A1. For example... Figure 3 The diagram shows a transistor voltage divider circuit, VControl, which divides the stepper motor's operating voltage VMotor via resistors R4 and R5. Resistors R4 and R5 are connected in series to divide the voltage, generating the operating voltage VControl of transistor A1. It can be seen that the operating voltage of transistor A1 is lower than the stepper motor's operating voltage VMotor. In practical applications of the stepper motor drive circuit provided by this invention, when multiple input power supplies are available, an external power supply can be used directly without the need for the transistor voltage divider circuit provided in this embodiment.

[0033] Furthermore, in the stepper motor drive circuit provided in this embodiment of the present invention, the transistor voltage divider circuit includes two resistors R4 and R5. The stepper motor operating voltage VMotor is connected to one end of the series connection of resistors R4 and R5, and the other end of the series connection of resistors R4 and R5 is grounded. The transistor operating voltage VControl is output from between resistors R4 and R5.

[0034] Furthermore, such as Figure 2As shown in the embodiment of this utility model, in the stepper motor drive circuit, the field-effect transistor is an N-type field-effect transistor A2. The motor boost control signal is input to the gate of the N-type field-effect transistor A2. The source of the N-type field-effect transistor A2 is connected to the gate, and the drain of the N-type field-effect transistor A2 is connected to the start coil of the stepper motor. The drive signal is output from the drain of the N-type field-effect transistor A2 to drive the stepper motor. The motor boost control signal Motor_Ctrol_Plus is connected to the gate (G) pin of the N-type field-effect transistor V2, and the power ground GND is connected to the source (S) pin of the N-type field-effect transistor V2.

[0035] Furthermore, in the stepper motor drive circuit provided in this embodiment of the invention, the drive circuit also includes a voltage regulator module, which is disposed between the operating voltage of the stepper motor and the starting coil of the stepper motor. The purpose of the voltage regulator module is to improve the stability of the drive signal and improve the control accuracy of the drive signal.

[0036] Furthermore, such as Figure 2 As shown in the embodiment of this utility model, the stepper motor drive circuit includes a voltage regulator module comprising a capacitor C1. The stepper motor's operating voltage is connected to one end of the capacitor, and the other end of the capacitor is simultaneously connected to the stepper motor's start-up coil and the drain of the N-type field-effect transistor A2. The stepper motor's operating voltage VMotor is connected to the drain (D) pin of the N-type field-effect transistor V2 via capacitor C1 and diode V1. One end of capacitor C1 is connected to the stepper motor's operating voltage VMotor, and the other end of capacitor C1 is simultaneously connected to the stepper motor's drive signal Motor_Phase, with the Motor_Phase terminal connected to the drain (D) pin of the N-type field-effect transistor V2. The main function of capacitor C1 is energy storage and filtering. When the stepper motor starts, capacitor C1 can provide additional current to help the stepper motor quickly reach its rated speed. Simultaneously, capacitor C1 can absorb ripple in the circuit, reduce voltage fluctuations, and ensure the smooth operation of the stepper motor, thereby improving the control accuracy of the stepper motor's rotation.

[0037] Furthermore, such as Figure 2As shown in the embodiment of this utility model, the stepper motor drive circuit includes a voltage regulator module further comprising a diode V1. Diode V1 and capacitor C1 are connected in parallel between the stepper motor's operating voltage and its starting coil. The negative terminal of diode V1 is connected to the stepper motor's operating voltage, and the positive terminal of diode V1 is connected to both the stepper motor's starting coil and the drain of the N-type field-effect transistor A2. The positive terminal of diode V1 is connected to the stepper motor's drive signal Motor_Phase, and the Motor_Phase terminal is connected to the drain (D) pin of the N-type field-effect transistor V2. The negative terminal of diode V1 is connected to the stepper motor's operating voltage VMotor. After each stepper motor stops working, capacitor C1 and diode V1 will quickly charge the stepper motor's starting coil within a short time to prevent a momentary surge in the stepper motor when it is started again.

[0038] Diode V1 is added because the starting coil in the stepper motor has winding inductance, which generates an induced electromotive force in the starting circuit, affecting the stepper motor's operating efficiency, motion accuracy, dynamic response, and stability characteristics. The main purpose of diode V1 is to quickly release this electromotive force, ensuring the stepper motor can operate stably for a long time. Diode V1 and capacitor C1 form a charging and discharging loop with the stepper motor's starting coil, providing control accuracy for the stepper motor.

[0039] When the stepper motor drive circuit provided in this embodiment of the utility model is working, the stepper motor's working voltage VMotor is first powered on, and the starting coil where the stepper motor's drive signal Motor_Phase is located is charged through capacitor C1. After charging is completed, the stepper motor's working voltage VMotor and the stepper motor's drive signal Motor_Phase form an open circuit. When the motor phase control signal Motor_Control is high, the collector and emitter of the NPN transistor A1 are disconnected, and the motor boost control signal Motor_Control_Plus is divided into the transistor's working voltage VControl through resistors R1 and R2 in series. At this time, the transistor's working voltage VControl is high, and the source and drain of the N-type field-effect transistor V2 are turned on, and the stepper motor's drive signal Motor_Phase is low. When the phase control signal Motor_Control is low, the collector and emitter of transistor A1 are connected, and Motor_Control_Plus is low. At this time, the source and drain of the motor boost control signal V2 are open-circuited, and the stepper motor drive signal Motor_Phase is high. When the stepper motor stops working, an induced current is generated due to the inductance of the stepper motor's starting coil. The residual current can flow through the positive terminal of V1 into the stepper motor's operating voltage VMotor, thereby achieving the purpose of current release.

[0040] As can be seen, the stepper motor drive circuit provided by this utility model consists of only five resistors, one capacitor, one diode, one NPN transistor, and one N-type field-effect transistor. The entire drive circuit has a simple structure and low cost. The entire drive circuit has a short working delay and low heat generation, making it suitable for high-speed, long-term operation of stepper motors.

[0041] The specific embodiments described above do not constitute a limitation on the scope of protection of this utility model. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the scope of protection of this utility model.

Claims

1. A drive circuit for a stepper motor, characterized in that: It includes a signal preprocessing module and a signal conversion module. The signal preprocessing module includes a transistor, and the signal conversion module includes a field-effect transistor. The transistor boosts and amplifies the phase control signal into a motor boost control signal, and the field-effect transistor converts the motor boost control signal into a stepper motor drive signal.

2. The driving circuit according to claim 1, characterized in that: The transistor is an NPN transistor (A1). The signal preprocessing module also includes two resistors (R1, R2). The phase control signal is input to the base of the transistor (A1). The operating voltage of the transistor (A1) is connected to the collector of the transistor (A1) via resistor (R1). The emitter of the transistor (A1) is grounded. One end of resistor (R2) is connected between resistor (R1) and the collector of the transistor (A1), and the other end of resistor (R2) is grounded. The motor boost control signal is output from the collector of the transistor (A1) to the signal conversion module.

3. The driving circuit according to claim 2, characterized in that: The signal preprocessing module also includes a resistor (R3) connected to the base of the transistor (A1), and the phase control signal is input to the base of the transistor (A1) via the resistor (R3).

4. The driving circuit according to claim 3, characterized in that: When the stepper motor is working, the operating voltage of the stepper motor provides power supply voltage to the drive circuit.

5. The driving circuit according to claim 4, characterized in that: The driving circuit also includes a transistor voltage divider circuit, through which the operating voltage of the stepper motor is divided to produce the operating voltage of the transistor (A1).

6. The driving circuit according to claim 5, characterized in that: The transistor voltage divider circuit includes two resistors (R4, R5). The operating voltage of the stepper motor is connected to one end of the series connection of resistors (R4 and R5), and the other end of the series connection of resistors (R4 and R5) is grounded. The operating voltage of the transistor is output from between resistors (R4 and R5).

7. The driving circuit according to any one of claims 2 to 6, characterized in that: The field-effect transistor is an N-type field-effect transistor (A2). The motor boost control signal is input to the gate of the N-type field-effect transistor (A2). The source of the N-type field-effect transistor (A2) is connected to the gate, and the drain of the N-type field-effect transistor (A2) is connected to the start coil of the stepper motor. The drive signal drives the stepper motor from the drain of the N-type field-effect transistor (A2).

8. The driving circuit according to claim 7, characterized in that: The drive circuit also includes a voltage regulator module, which is disposed between the operating voltage of the stepper motor and the starting coil of the stepper motor.

9. The driving circuit according to claim 8, characterized in that: The voltage regulator module includes a capacitor (C1), the operating voltage of the stepper motor is connected to one end of the capacitor, and the other end of the capacitor is connected to both the start coil of the stepper motor and the drain of the N-type field-effect transistor (A2).

10. The driving circuit according to claim 9, characterized in that: The voltage regulator module also includes a diode (V1), which is connected in parallel with the capacitor (C1) between the operating voltage of the stepper motor and the starting coil of the stepper motor. The negative terminal of the diode (V1) is connected to the operating voltage of the stepper motor, and the positive terminal of the diode (V1) is connected to both the starting coil of the stepper motor and the drain of the N-type field-effect transistor (A2).

Images