Low-cost control signal level conversion circuit

Abstract

The utility model relates to the field of stepping motor driving circuits. The utility model discloses a low-cost control signal level conversion circuit, which comprises a power supply end, a first signal input end, a second signal input end, an MOS tube Q1, an MOS tube Q2, an MOS tube Q3, an MOS tube Q4, a positive electrode output end, a negative electrode output end and a grounding end, the grid electrode of the MOS tube Q1 is connected with the grid electrode of the MOS tube Q3, the grid electrode of the MOS tube Q2 is connected with the grid electrode of the MOS tube Q4, the input end of the MOS tube Q1 and the input end of the MOS tube Q2 are both connected with the power supply end, and the positive electrode output end is connected with the negative electrode output end. The first signal input end is connected between the grid electrode of the MOS tube Q1 and the grid electrode of the MOS tube Q3, the second signal input end is connected between the grid electrode of the MOS tube Q2 and the grid electrode of the MOS tube Q4, the positive electrode output end is connected between the output end of the MOS tube Q1 and the input end of the MOS tube Q3, and the negative electrode output end is connected between the output end of the MOS tube Q2 and the input end of the MOS tube Q4. Four separation devices are adopted to realize different low-cost level conversion schemes, and the level of two poles of the stepping motor is controlled to be converted between a high level and a low level.

Description

Technical Field

[0001] This utility model relates to the field of stepper motor drive circuits, and in particular to a low-cost control signal level conversion circuit. Background Technology

[0002] Stepper motors require control signals to switch between different voltage levels during operation to control the rotation direction of the motor shaft. Stepper motor drive circuits typically use conversion chips to control the voltage levels of the control signals, allowing for switching between different signal levels. Because a dedicated conversion chip is required, and a signal amplification circuit is needed between the conversion chip and the stepper motor, the cost remains high. Utility Model Content

[0003] The purpose of this invention is to provide a low-cost control signal level conversion circuit that uses discrete devices to achieve low-cost control signal conversion, enabling the level of the two poles of the stepper motor to switch between high and low levels.

[0004] To achieve the above objectives, this utility model adopts the following technical solution: a low-cost control signal level conversion circuit, comprising: a power supply terminal, a first signal input terminal, a second signal input terminal, MOSFETs Q1, Q2, Q3, and Q4, a positive output terminal, a negative output terminal, and a ground terminal. The gate of MOSFET Q1 is connected to the gate of MOSFET Q3, and the gate of MOSFET Q2 is connected to the gate of MOSFET Q4. The input terminals of MOSFETs Q1 and Q2 are both connected to the power supply terminal, and the output terminal of MOSFET Q1 is connected to the ground terminal. The input terminal of MOSFET Q3 is connected to the input terminal of MOSFET Q2. The output terminals of both MOSFET Q3 and MOSFET Q4 are connected to ground. The first signal input terminal is connected between the gates of MOSFET Q1 and MOSFET Q3. The second signal input terminal is connected between the gates of MOSFET Q2 and MOSFET Q4. The positive output terminal is connected between the output terminal of MOSFET Q1 and the input terminal of MOSFET Q3. The negative output terminal is connected between the output terminal of MOSFET Q2 and the input terminal of MOSFET Q4.

[0005] Preferably, both MOS transistors Q1 and Q2 are P-channel MOS transistors.

[0006] Preferably, both MOS transistors Q3 and Q4 are N-channel MOS transistors.

[0007] Preferably, the low-cost control signal level conversion circuit further includes a control chip U1, wherein the first signal input terminal is connected to the non-inverting output pin of the control chip U1, and the second signal input terminal is connected to the inverting output pin of the control chip U1.

[0008] Preferably, the low-cost control signal level conversion circuit further includes a pull-up resistor R1, the two ends of which are connected to the input terminal and the gate of the MOSFET Q1, respectively. The pull-up resistor R1 is the pull-up resistor for the P-channel MOSFET Q1, ensuring that the P-channel MOSFET Q1 is in the off state when there is no input signal.

[0009] Preferably, the low-cost control signal level conversion circuit further includes a pull-up resistor R2, the two ends of which are connected to the input terminal and the gate of the MOSFET Q2, respectively. The pull-up resistor R2 is the pull-up resistor for the P-channel MOSFET Q2, ensuring that the P-channel MOSFET Q2 is in the off state when there is no input signal.

[0010] Preferably, the low-cost control signal level conversion circuit further includes a pull-down resistor R3, the two ends of which are connected to the gate and output terminal of the MOSFET Q3, respectively. The pull-down resistor R3 is a pull-down resistor for the N-channel MOSFET Q3, ensuring that the N-channel MOSFET Q3 is in the off state when there is no input signal.

[0011] Preferably, the low-cost control signal level conversion circuit further includes a pull-down resistor R4, the two ends of which are connected to the gate and output terminal of the MOSFET Q4, respectively. The pull-down resistor R4 is a pull-down resistor for the N-channel MOSFET Q4, ensuring that the N-channel MOSFET Q4 is in the off state when there is no input signal.

[0012] Preferably, the grounding terminal is connected to the AGND pin of the control chip U1.

[0013] Preferably, the low-cost control signal level conversion circuit further includes a stepper motor, wherein the positive terminal of the stepper motor is connected to the positive output terminal and the negative terminal of the stepper motor is connected to the negative output terminal.

[0014] The beneficial effects of this invention are as follows: The first and second signal input terminals receive high and low levels respectively as needed, controlling the on / off state of four MOSFETs. When the first and second signal input terminals are supplied with low and high levels respectively, the positive and negative output terminals output high and low levels respectively; when the first and second signal input terminals are supplied with high and low levels respectively, the positive and negative output terminals output low and high levels respectively. The PWM signal is amplified and driven by an amplifier circuit composed of four MOSFETs, and low-cost high / low level switching is achieved using four discrete devices, enabling the control of the stepper motor's two poles to switch between high and low levels. Attached Figure Description

[0015] The accompanying drawings further illustrate the present invention, but the embodiments in the drawings do not constitute any limitation on the present invention.

[0016] Figure 1 A circuit diagram provided for one embodiment of this utility model;

[0017] Figure 2 A PWM signal diagram of a control chip provided in an embodiment of this utility model. Detailed Implementation

[0018] The specific embodiments of this utility model will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the scope of this utility model.

[0019] It should be noted that, in this utility model, unless otherwise stated, when an element is referred to as being "connected to" another element, it can be directly connected to the other element or there may be an intervening element present at the same time.

[0020] like Figure 1 As shown in the figure, a low-cost control signal level conversion circuit provided by an embodiment of the present invention includes: a power supply terminal, a first signal input terminal, a second signal input terminal, MOSFETs Q1, Q2, Q3, and Q4, a positive output terminal (+), a negative output terminal (-), and a ground terminal. The gate of MOSFET Q1 is connected to the gate of MOSFET Q3, and the gate of MOSFET Q2 is connected to the gate of MOSFET Q4. The input terminals of MOSFETs Q1 and Q2 are both connected to the power supply terminal, and the output terminal of MOSFET Q1 is connected to the ground terminal. The input terminal of Q3 is connected to the input terminal of MOSFET Q2. The output terminals of both MOSFET Q3 and Q4 are connected to ground. The first signal input terminal is connected between the gates of MOSFET Q1 and Q3. The second signal input terminal is connected between the gates of MOSFET Q2 and Q4. The positive output terminal + is connected between the output terminal of MOSFET Q1 and the input terminal of MOSFET Q3. The negative output terminal - is connected between the output terminal of MOSFET Q2 and the input terminal of MOSFET Q4. The power supply terminal is connected to a 5V DC power supply.

[0021] Both MOSFETs Q1 and Q2 are P-channel MOSFETs. The input terminal of MOSFETs Q1 and Q2 is the source, and the output terminal of MOSFETs Q1 and Q2 is the drain.

[0022] Both MOSFETs Q3 and Q4 are N-channel MOSFETs. The input terminal of MOSFETs Q3 and Q4 is the drain, and the output terminal of MOSFETs Q3 and Q4 is the source.

[0023] The low-cost control signal level conversion circuit also includes a control chip U1, which is a chip with PWM drive function. The first signal input terminal is connected to the non-inverting output pin of the control chip U1, and the second signal input terminal is connected to the inverting output pin of the control chip U1. The ground terminal is connected to the AGND analog ground pin of the control chip U1.

[0024] The low-cost control signal level conversion circuit also includes a pull-up resistor R1, the two ends of which are connected to the input terminal and the gate of the MOS transistor Q1, respectively.

[0025] The low-cost control signal level conversion circuit also includes a pull-up resistor R2, the two ends of which are connected to the input terminal and the gate of the MOS transistor Q2, respectively.

[0026] The low-cost control signal level conversion circuit also includes a pull-down resistor R3, the two ends of which are connected to the gate and the output terminal of the MOS transistor Q3, respectively.

[0027] The low-cost control signal level conversion circuit also includes a pull-down resistor R4, the two ends of which are connected to the gate and the output terminal of the MOS transistor Q4, respectively.

[0028] The low-cost control signal level conversion circuit also includes a stepper motor, with the positive terminal of the stepper motor connected to the positive output terminal + and the negative terminal of the stepper motor connected to the negative output terminal -.

[0029] The working principle of this utility model is as follows: For the driving circuit provided in this embodiment, please refer to... Figure 2 The first signal input terminal is the positive output signal of the PWM Sample inside the motor control chip, and the second signal input terminal is the inverted output signal of the PWM Sample inside the motor control chip. When the level of the first signal input terminal is low, the level of the second signal input terminal is simultaneously high, that is, P-channel MOSFET Q1 and N-channel MOSFET Q4 are turned on, P-channel MOSFET Q2 and N-channel MOSFET Q3 are turned off, the positive output terminal is high, and the negative output terminal is low.

[0030] If the level of the first input signal terminal is high, the level of the second input signal terminal is simultaneously low. That is, P-channel MOSFET Q1 and N-channel MOSFET Q4 are cut off, while P-channel MOSFET Q2 and N-channel MOSFET Q3 are turned on. The positive output terminal is low, and the negative output terminal is high. The PWM signal is amplified and driven by an H-bridge amplifier circuit composed of four MOSFETs, thereby controlling the direction of rotation of the stepper motor shaft.

[0031] The technical features of the embodiments described above can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. It should be noted that those skilled in the art can make several modifications and improvements without departing from the concept of this utility model, and these should all be considered to be within the scope of this specification.

Claims

1. A low cost control signal level shifting circuit, characterized by: include: The system includes a power supply terminal, a first signal input terminal, a second signal input terminal, MOSFETs Q1, Q2, Q3, and Q4, a positive output terminal, a negative output terminal, and a ground terminal. The gate of MOSFET Q1 is connected to the gate of MOSFET Q3, and the gate of MOSFET Q2 is connected to the gate of MOSFET Q4. The input terminals of MOSFETs Q1 and Q2 are both connected to the power supply terminal. The output terminal of MOSFET Q1 is connected to the input terminal of MOSFET Q3, and the output terminal of MOSFET Q2 is connected to the input terminal of MOSFET Q4. The output terminals of MOSFETs Q3 and Q4 are both connected to the ground terminal. The first signal input terminal is connected between the gates of MOSFETs Q1 and Q3, the second signal input terminal is connected between the gates of MOSFETs Q2 and Q4, the positive output terminal is connected between the output terminal of MOSFET Q1 and the input terminal of MOSFET Q3, and the negative output terminal is connected between the output terminal of MOSFET Q2 and the input terminal of MOSFET Q4.

2. The low cost control signal level shifting circuit of claim 1, wherein: Both MOSFETs Q1 and Q2 are P-channel MOSFETs.

3. The low cost control signal level shifting circuit according to claim 1 or 2, characterized in that: Both MOSFETs Q3 and Q4 are N-channel MOSFETs.

4. The low cost control signal level shifting circuit of claim 1, wherein: It also includes a control chip U1, with the first signal input terminal connected to the non-inverting output pin of the control chip U1 and the second signal input terminal connected to the inverting output pin of the control chip U1.

5. The low cost control signal level shifting circuit of claim 1, wherein: It also includes a pull-up resistor R1, the two ends of which are connected to the input terminal and the gate of the MOS transistor Q1, respectively.

6. The low cost control signal level shifting circuit of claim 1, wherein: It also includes a pull-up resistor R2, the two ends of which are connected to the input terminal and the gate of the MOS transistor Q2, respectively.

7. The low cost control signal level shifting circuit of claim 1, wherein: It also includes a pull-down resistor R3, the two ends of which are connected to the gate and the output terminal of the MOSFET Q3, respectively.

8. The low cost control signal level shifting circuit of claim 1, wherein: It also includes a pull-down resistor R4, the two ends of which are connected to the gate and the output terminal of the MOSFET Q4, respectively.

9. The low-cost control signal level conversion circuit according to claim 4, characterized in that: The grounding terminal is connected to the AGND pin of the control chip U1.

10. The low cost control signal level shifting circuit of claim 1, wherein: It also includes a stepper motor, wherein the positive terminal of the stepper motor is connected to the positive output terminal and the negative terminal of the stepper motor is connected to the negative output terminal.

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