A PWM driving circuit, a substrate and a development board

Abstract

The application provides a PWM driving circuit, a substrate and a development board, relates to the technical field of PWM driving, and the circuit comprises a power supply access circuit, a voltage conversion circuit, a PWM output circuit, a signal input circuit and an output interface; the power supply access circuit is electrically connected with the voltage conversion circuit, the voltage conversion circuit is electrically connected with the output interface; the signal input circuit and the PWM output circuit are respectively electrically connected with the signal input circuit and the output interface. The power supply access circuit accesses a power supply voltage; the voltage conversion circuit converts the power supply voltage to obtain a working voltage; the signal input circuit accesses a logic power supply and a communication signal; the PWM output circuit outputs multiple PWM signals according to the logic power supply and the communication signal; the output interface outputs the multiple PWM signals and the working voltage corresponding to the multiple PWM signals. The signal input circuit and the output interface provide an interactive interface with a single-chip microcomputer and controlled equipment, reduce the complexity of circuit connection, and improve flexibility.

Description

Technical Field

[0001] This application relates to the field of PWM driving technology, and in particular to a PWM driving circuit, substrate and development board. Background Technology

[0002] A development board (demo board) is a circuit board used for embedded system development. It includes a series of hardware components such as a central processing unit (CPU), memory, input devices, output devices, data bus, and external resource interfaces. Development boards are generally customized by embedded system developers according to their development needs, or users can design and implement them themselves. Development boards are designed for beginners to understand and learn about the system's hardware and software. Some development boards also provide a basic integrated development environment (IDE), software source code, and hardware schematics. Common development boards include those for 51 microcontrollers, ARM (Advanced RISC Machine), FPGA (Field Programmable Gate Array), and DSP (Digital Signal Processor).

[0003] When beginners are learning microcontrollers, they often buy existing microcontroller development boards. These boards integrate various functional modules to meet different development needs, such as motor drive modules, PWM (Pulse Width Modulation) drive modules, display modules, button modules, tracking modules, and so on.

[0004] Taking a microcontroller development board with an integrated PWM driver module as an example, existing microcontroller development boards reduce the number of I / O (input / output) interfaces of the microcontroller or functional modules in order to simplify circuit design. This requires beginners to use I / O interface expansion boards to increase the number of I / O interfaces for easier debugging, increasing the complexity of circuit connections. In addition, integrating the microcontroller and PWM driver module on a single development board makes it difficult for beginners to understand the interaction process between the PWM driver module and the microcontroller, and it is also inconvenient to adjust the electrical connection between the PWM driver module and the microcontroller, resulting in low flexibility. Utility Model Content

[0005] This application provides a PWM drive circuit, a substrate, and a development board to reduce the complexity of circuit connections and improve the flexibility of connection between the PWM drive module and the microcontroller.

[0006] In a first aspect, this application provides a PWM driving circuit, which includes: a power supply input circuit, a voltage conversion circuit, a PWM output circuit, a signal input circuit, and an output interface;

[0007] The power input circuit is electrically connected to the voltage conversion circuit, and the voltage conversion circuit is electrically connected to the output interface; the signal input circuit is electrically connected to the PWM output circuit, and the PWM output circuit is electrically connected to the output interface.

[0008] The power supply circuit is configured to receive the power supply voltage.

[0009] The voltage conversion circuit is configured to convert the supply voltage to obtain the operating voltage, and transmit the operating voltage to the output interface;

[0010] The signal input circuit is configured to connect to logic power and communication signals;

[0011] The PWM output circuit is configured to output multiple PWM signals based on the received logic power and communication signals, and transmit the multiple PWM signals to the output interface.

[0012] The output interface is configured to output the multiple PWM signals and the operating voltage corresponding to the multiple PWM signals.

[0013] In one possible design, the power access circuit includes: a first power interface, a first diode, and a switch;

[0014] The first, third, and fourth terminals of the first power interface are all grounded. The second terminal of the first power interface is electrically connected to the positive terminal of the first diode for receiving the power supply voltage. The negative terminal of the first diode is electrically connected to the input terminal of the switch.

[0015] The output terminal of the switch serves as the output terminal of the power supply circuit, used to output the power supply voltage.

[0016] In one possible design, the voltage conversion circuit includes: a first capacitor, a second capacitor, a third capacitor, a fourth capacitor, a fifth capacitor, a sixth capacitor, a seventh capacitor, a first resistor, a second resistor, a second diode, an inductor, a fuse, and a voltage conversion chip;

[0017] The first terminal of the first capacitor is electrically connected to the first terminal of the second capacitor, the first terminal of the third capacitor, the first terminal of the fourth capacitor, and the seventh terminal of the voltage conversion chip, respectively, for receiving the power supply voltage;

[0018] The first terminal of the voltage conversion chip is electrically connected to the first terminal of the fifth capacitor, and the second terminal of the fifth capacitor is electrically connected to the eighth terminal of the voltage conversion chip, the negative terminal of the second diode, and the first terminal of the inductor, respectively.

[0019] The second end of the inductor is electrically connected to the first end of the sixth capacitor, the first end of the seventh capacitor, the first end of the first resistor, and the first end of the fuse, respectively.

[0020] The second end of the first resistor is electrically connected to the fourth end of the voltage conversion chip and the first end of the second resistor, respectively.

[0021] The second end of the fuse serves as the output terminal of the voltage conversion circuit, used to output the operating voltage;

[0022] The second terminal of the first capacitor, the second terminal of the second capacitor, the second terminal of the third capacitor, the second terminal of the fourth capacitor, the positive terminal of the second diode, the second terminal of the sixth capacitor, the second terminal of the seventh capacitor, the second terminal of the second resistor, the sixth terminal of the voltage conversion chip, and the ninth terminal of the voltage conversion chip are all grounded.

[0023] In one possible design, the signal input circuit includes: a second power interface, a transistor, a third resistor, and an eighth capacitor; the communication signals include: a clock signal and a data signal.

[0024] The first terminal of the second power interface is grounded, and the second terminal of the second power interface is connected to the first voltage;

[0025] The second terminal of the transistor is electrically connected to the second terminal of the second power interface, the first terminal of the transistor is electrically connected to the first terminal of the eighth capacitor, and serves as the first output terminal of the signal input circuit for outputting the logic power supply; the control terminal of the transistor is electrically connected to the first terminal of the third resistor.

[0026] The third terminal of the second power interface is used to receive the clock signal, and the fourth terminal of the second power interface is used to receive the data signal.

[0027] The second terminal of the third resistor and the second terminal of the eighth capacitor are both grounded.

[0028] In one possible design, the PWM output circuit includes: a ninth capacitor, a fourth resistor, a fifth resistor, and a PWM generation chip;

[0029] The first, second, third, fourth, fifth, fourteenth, twenty-third, twenty-fourth, and twenty-fifth terminals of the PWM generation chip are all grounded.

[0030] The sixth terminal of the PWM generation chip outputs a first PWM signal, the seventh terminal of the PWM generation chip outputs a second PWM signal, the eighth terminal of the PWM generation chip outputs a third PWM signal, the ninth terminal of the PWM generation chip outputs a fourth PWM signal, the tenth terminal of the PWM generation chip outputs a fifth PWM signal, the eleventh terminal of the PWM generation chip outputs a sixth PWM signal, the twelfth terminal of the PWM generation chip outputs a seventh PWM signal, the thirteenth terminal of the PWM generation chip outputs an eighth PWM signal, the fifteenth terminal of the PWM generation chip outputs a ninth PWM signal, the sixteenth terminal of the PWM generation chip outputs a tenth PWM signal, the seventeenth terminal of the PWM generation chip outputs an eleventh PWM signal, the eighteenth terminal of the PWM generation chip outputs a twelfth PWM signal, the nineteenth terminal of the PWM generation chip outputs a thirteenth PWM signal, the twentieth terminal of the PWM generation chip outputs a fourteenth PWM signal, the twenty-first terminal of the PWM generation chip outputs a fifteenth PWM signal, and the twenty-second terminal of the PWM generation chip outputs a sixteenth PWM signal.

[0031] The 26th terminal of the PWM generation chip is electrically connected to the second terminal of the fifth resistor, and the 27th terminal of the PWM generation chip is electrically connected to the second terminal of the fourth resistor;

[0032] The 28th terminal of the PWM generation chip is electrically connected to the second terminal of the ninth capacitor, the first terminal of the fourth resistor, and the first terminal of the fifth resistor, respectively, for connecting to the logic power supply;

[0033] The first terminal of the ninth capacitor is grounded.

[0034] In one possible design, the output interface includes: a first output plug-in, a second output plug-in, a third output plug-in, a fourth output plug-in, a fifth output plug-in, and a sixth output plug-in;

[0035] The first terminal of the first output plug is connected to the first PWM signal, the second terminal of the first output plug is connected to the second PWM signal, the third terminal of the first output plug is connected to the third PWM signal, the fourth terminal of the first output plug is connected to the fourth PWM signal, the fifth terminal of the first output plug is connected to the fifth PWM signal, the sixth terminal of the first output plug is connected to the sixth PWM signal, the seventh terminal of the first output plug is connected to the seventh PWM signal, and the eighth terminal of the first output plug is connected to the eighth PWM signal.

[0036] The first, second, third, fourth, fifth, sixth, seventh, and eighth terminals of the second output plug are all connected to the operating voltage.

[0037] The first, second, third, fourth, fifth, sixth, seventh, and eighth terminals of the third output plug-in are all grounded.

[0038] The first terminal of the fourth output plug is connected to the ninth PWM signal, the second terminal of the fourth output plug is connected to the tenth PWM signal, the third terminal of the fourth output plug is connected to the eleventh PWM signal, the fourth terminal of the fourth output plug is connected to the twelfth PWM signal, the fifth terminal of the fourth output plug is connected to the thirteenth PWM signal, the sixth terminal of the fourth output plug is connected to the fourteenth PWM signal, the seventh terminal of the fourth output plug is connected to the fifteenth PWM signal, and the eighth terminal of the fourth output plug is connected to the sixteenth PWM signal.

[0039] The first, second, third, fourth, fifth, sixth, seventh, and eighth terminals of the fifth output plug are all connected to the operating voltage.

[0040] The first, second, third, fourth, fifth, sixth, seventh, and eighth terminals of the sixth output plug-in are all grounded.

[0041] In one possible design, the second diode is a Schottky diode.

[0042] In one possible design, the PWM generation chip is the PCA9685.

[0043] In a second aspect, this application provides a substrate comprising: a PWM drive circuit as described in the first aspect.

[0044] Thirdly, this application provides a development board, including: a substrate and a main control circuit as described in the second aspect.

[0045] The beneficial effects of the embodiments of this application are as follows:

[0046] In this embodiment, the PWM drive circuit includes a power input circuit and a voltage conversion circuit. It receives the supply voltage and performs level conversion to obtain the operating voltage, which is then transmitted to the output interface to power external controlled devices. The PWM output circuit outputs multiple PWM signals to provide PWM control signals to external controlled devices. Additionally, it includes a signal input circuit and an output interface, providing corresponding interfaces for interaction between the PWM drive circuit, the main control circuit (i.e., the microcontroller section), and the external controlled devices. This not only implements the PWM drive control function but also facilitates debugging, eliminating the need to increase the number of I / O interfaces through an I / O interface expansion board, thus reducing the complexity of circuit connections during debugging. Furthermore, the PWM drive circuit can be electrically connected to different models of microcontrollers as needed. This facilitates adjusting the electrical connection relationship between the PWM drive circuit and the microcontroller, and also allows for a better understanding of the interaction process between them, resulting in greater flexibility. Attached Figure Description

[0047] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other embodiments can be obtained based on these drawings.

[0048] Figure 1 This is a schematic diagram of the structure of a PWM drive circuit provided in an embodiment of this application;

[0049] Figure 2 This is a schematic diagram of a power supply access circuit provided in an embodiment of this application;

[0050] Figure 3 This is a schematic diagram of a voltage conversion circuit provided in an embodiment of this application;

[0051] Figure 4 This is a schematic diagram of a signal input circuit provided in an embodiment of this application;

[0052] Figure 5 This is a schematic diagram of the structure of a PWM output circuit provided in an embodiment of this application;

[0053] Figure 6 This is a schematic diagram of an output interface provided in an embodiment of this application. Detailed Implementation

[0054] In this application, "at least one" means one or more, and "more than one" means two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can mean: A alone, A and B simultaneously, or B alone, where A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one of a, b, or c alone can mean: a alone, b alone, c alone, a combination of a and b, a combination of a and c, a combination of b and c, or a, b, and c, where a, b, and c can be single or multiple. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0055] The terms “center,” “longitudinal,” “lateral,” “up,” “down,” “left,” “right,” “front,” and “rear,” etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0056] The terms "connected" and "connected" should be interpreted broadly. For example, in circuit structures, "connected" or "connected" can refer not only to physical connections but also to electrical or signal connections. This could be a direct connection (physical connection) or an indirect connection via at least one intermediate component, as long as the circuit is connected. It could also refer to the internal connection between two components. Similarly, a signal connection can refer to a connection via a circuit or a medium, such as radio waves. Those skilled in the art will understand the specific meaning of these terms in this application based on the specific circumstances.

[0057] To reduce the complexity of circuit connections during debugging and improve the flexibility of the connection between the PWM drive module and the microcontroller, this application divides the microcontroller development board, which integrates multiple functional modules, into blocks. Specifically, it separates the main control circuit (i.e., the microcontroller part) from the PWM drive module. A separate PWM drive circuit is set up, and the I / O interfaces of the chips required for debugging are set within the PWM drive circuit. This facilitates debugging without needing an I / O interface expansion board to increase the number of I / O interfaces, thus reducing the complexity of circuit connections during debugging. Furthermore, the separately set PWM drive circuit allows users to easily connect it to different models of main control circuits (i.e., the microcontroller part) as needed. This facilitates adjusting the electrical connection relationship between the PWM drive circuit and the microcontroller, while also allowing for a better understanding of the interaction process between the PWM drive circuit and the microcontroller, resulting in greater flexibility.

[0058] See Figure 1 , Figure 1 This is a schematic diagram of a PWM drive circuit provided in an embodiment of this application, as shown below. Figure 1 As shown, the PWM drive circuit 1000 may include: a power supply input circuit 100, a voltage conversion circuit 200, a PWM output circuit 300, a signal input circuit 400, and an output interface 500.

[0059] The power input circuit 100 is electrically connected to the voltage conversion circuit 200, and the voltage conversion circuit 200 is electrically connected to the output interface 500; the signal input circuit 300 is electrically connected to the PWM output circuit 400, and the PWM output circuit 400 is electrically connected to the output interface 500.

[0060] The power supply circuit 100 is set to receive the power supply voltage VIN.

[0061] The voltage conversion circuit 200 is configured to convert the supply voltage VIN to obtain the operating voltage VM, and transmit the operating voltage VM to the output interface 500.

[0062] The signal input circuit 400 is configured to connect to logic power and communication signals.

[0063] The PWM output circuit 300 is configured to output multiple PWM signals based on the received logic power supply and communication signals, and transmit the multiple PWM signals to the output interface 500.

[0064] Output interface 500 is configured to output multiple PWM signals and the corresponding operating voltage VM for each PWM signal.

[0065] The PWM drive circuit in this application is used to output multiple PWM signals. It also obtains the operating voltage through a voltage conversion circuit, using the PWM signals and an independent power supply to provide PWM control signals and power to external servo motors or LED (Light-Emitting Diode) light strips. It is commonly used in multi-servo arm or track differential control in intelligent vehicles and robots; it can also be used for zoned dimming and gradient effects control in light shows and LED light strips; additionally, it is used for proportional control of valves, fans, pumps, etc., in automated equipment, for example, adjusting fan speed.

[0066] The power supply circuit 100 can draw power from a DC power source or a battery to supply voltage VIN to the voltage conversion circuit 200. In one example, the supply voltage VIN can be 3.3V.

[0067] The voltage conversion circuit 200 converts the supply voltage VIN to obtain the operating voltage VM. In one example, the voltage conversion circuit 200 boosts the supply voltage VIN to obtain an operating voltage VM of 5V. The operating voltage VM is then transmitted to the output interface 500 to power an external servo motor or LED strip.

[0068] The PWM output circuit outputs multiple PWM signals based on the received logic power and communication signals, and transmits these multiple PWM signals to the output interface. This allows external servos or LED strips to connect to the corresponding PWM signals through the output interface, and also allows users to detect the waveform of the PWM signals based on the output interface.

[0069] The signal input circuit and output interface are reserved by the PWM drive circuit for interaction with the main control circuit (i.e., the microcontroller section) or external controlled devices. The signal input circuit receives signals from the main control circuit (i.e., the microcontroller section), while the output interface receives signals from the PWM drive circuit, which need to be transmitted to external controlled devices, such as external servos or LED strips. It should be noted that, in addition to providing multiple PWM signals to external controlled devices, the output interface also provides independent power to external controlled devices through the operating voltage VM, facilitating the control of multiple external controlled devices.

[0070] The input interface 400 is configured to receive logic power and communication signals, and transmit them to the PWM output circuit. The output interface 500 is configured to output multiple PWM signals and their corresponding operating voltages, and transmit them to external controlled devices to provide PWM control signals and power supply to the external controlled devices.

[0071] In this embodiment, the PWM drive circuit includes a power input circuit and a voltage conversion circuit. It receives the supply voltage and performs level conversion to obtain the operating voltage, which is then transmitted to the output interface to power external controlled devices. The PWM output circuit outputs multiple PWM signals to provide PWM control signals to external controlled devices. Additionally, it includes a signal input circuit and an output interface, providing corresponding interfaces for interaction between the PWM drive circuit, the main control circuit (i.e., the microcontroller section), and the external controlled devices. This not only implements the PWM drive control function but also facilitates debugging, eliminating the need to increase the number of I / O interfaces through an I / O interface expansion board, thus reducing the complexity of circuit connections during debugging. Furthermore, the PWM drive circuit can be electrically connected to different models of microcontrollers as needed. This facilitates adjusting the electrical connection relationship between the PWM drive circuit and the microcontroller, and also allows for a better understanding of the interaction process between them, resulting in greater flexibility.

[0072] In one possible embodiment, see Figure 2 , Figure 2 This is a schematic diagram of a power supply access circuit provided in an embodiment of this application, as shown below. Figure 2 As shown, the power supply circuit 100 may include: a first power interface H1, a first diode D1, and a switch SW.

[0073] The first, third, and fourth terminals of the first power interface H1 are all grounded. The second terminal of the first power interface H1 is electrically connected to the positive terminal of the first diode D1 for connecting to the power supply voltage. The negative terminal of the first diode D1 is electrically connected to the input terminal of the switch SW.

[0074] The output terminal of switch SW serves as the output terminal of power supply circuit 100, used to output the power supply voltage VIN.

[0075] The first power interface H1 is a reserved power interface in this application. A power supply voltage can be connected through this interface, and the power supply voltage is output as VIN after passing through diode D1. The first power interface H1 can be connected to a DC power source or a battery, providing the corresponding power supply voltage VIN. After the power supply voltage is connected to the first power interface H1, the power supply can be controlled by the switch SW to provide power to the subsequent circuits. In one example, the switch SW can be a DIP switch. When the switch is switched to one side, the power supply is turned on to provide the power supply voltage VIN to the subsequent circuits; when the switch is switched to the other side, the power supply is turned off, and the power supply voltage VIN is not provided to the subsequent circuits.

[0076] In one possible embodiment, see Figure 3 , Figure 3 This is a schematic diagram of a voltage conversion circuit provided in an embodiment of this application, as shown below. Figure 3As shown, the voltage conversion circuit 200 may include: a first capacitor C1, a second capacitor C2, a third capacitor C3, a fourth capacitor C4, a fifth capacitor C5, a sixth capacitor C6, a seventh capacitor C7, a first resistor R1, a second resistor R2, a second diode D2, an inductor L1, a fuse F1, and a voltage conversion chip U1.

[0077] The first terminal of the first capacitor C1 is electrically connected to the first terminals of the second capacitor C2, the third capacitor C3, the fourth capacitor C4, and the seventh terminal of the voltage conversion chip U1, respectively, for connecting to the power supply voltage VIN.

[0078] The first terminal BOOT of the voltage conversion chip U1 is electrically connected to the first terminal of the fifth capacitor C5. The second terminal of the fifth capacitor C5 is electrically connected to the eighth terminal PH of the voltage conversion chip U1, the negative terminal of the second diode D2, and the first terminal of the inductor L1.

[0079] The second end of inductor L1 is electrically connected to the first end of the sixth capacitor C6, the first end of the seventh capacitor C7, the first end of the first resistor R1, and the first end of fuse F1.

[0080] The second terminal of the first resistor R1 is electrically connected to the fourth terminal VSENSE of the voltage conversion chip U1 and the first terminal of the second resistor R2, respectively.

[0081] The second terminal of fuse F1 serves as the output terminal of voltage conversion circuit 200, used to output operating voltage VM.

[0082] The second terminals of the first capacitor C1, the second terminals of the second capacitor C2, the second terminals of the third capacitor C3, the second terminals of the fourth capacitor C3, the positive terminal of the second diode D2, the second terminals of the sixth capacitor C6, the second terminals of the seventh capacitor C7, the second terminals of the second resistor R2, the sixth terminal of the voltage conversion chip U1, and the ninth terminal of the voltage conversion chip U1 are all grounded.

[0083] The voltage conversion circuit 200 is used to convert the supply voltage VIN to the operating voltage VM, that is, to convert the 3.3V supply voltage VIN to the 5V operating voltage VM. The voltage conversion chip U1 is a boost converter and can be used as a BOOST circuit.

[0084] The fourth terminal VSENSE of the voltage conversion chip U1 is used to detect current and realize overcurrent protection. The first resistor R1 and the second resistor R2 form a voltage divider feedback network. By adjusting the resistance values ​​of the first resistor R1 and the second resistor R2, the operating voltage VM can be stabilized at 5V.

[0085] The first capacitor C1, the second capacitor C2, the third capacitor C3, the fourth capacitor C4, the sixth capacitor C6, and the seventh capacitor C7 are filter capacitors, which can filter out ripple and provide a more stable operating voltage VM.

[0086] In one possible embodiment, the second diode D2 is a Schottky diode, which has the functions of rectification, freewheeling, and voltage regulation, and can conduct the stored energy current to the output terminal.

[0087] In one possible embodiment, see Figure 4 , Figure 4 This is a schematic diagram of a signal input circuit provided in an embodiment of this application, as shown below. Figure 4 As shown, the signal input circuit 400 includes: a second power interface H2, a transistor Q1, a third resistor R3, and an eighth capacitor C8; the communication signals include: a clock signal SCL and a data signal SDA.

[0088] The first terminal of the second power interface H2 is grounded, and the second terminal of the second power interface H2 is connected to the first voltage VI.

[0089] The second terminal of transistor Q1 is electrically connected to the second terminal of the second power interface H2, and the first terminal of transistor Q1 is electrically connected to the first terminal of the eighth capacitor C8, and serves as the first output terminal of the signal input circuit 400 for outputting logic power supply VIO.

[0090] The control terminal of transistor Q1 is electrically connected to the first terminal of the third resistor R3.

[0091] The third terminal of the second power interface H2 is used to connect the clock signal SCL, and the fourth terminal of the second power interface H2 is used to connect the data signal SDA.

[0092] The second terminal of the third resistor R3 and the second terminal of the eighth capacitor C8 are both grounded.

[0093] The second power interface H2 can receive a first voltage VI from the microcontroller. The first voltage VI can be 3.3V. After passing through the first transistor Q1, the first voltage VI yields a second voltage VIO. The second voltage VIO is also 3.3V, providing logic power to the PWM output circuit.

[0094] In this application, the first transistor Q1 can be a bipolar transistor or a field-effect transistor (FET). For example, when the first transistor Q1 is a bipolar transistor, its control terminal refers to the base of the bipolar transistor, and the first terminal can be the collector or emitter of the bipolar transistor, while the corresponding second terminal can be the emitter or collector of the bipolar transistor. When the first transistor Q1 is a field-effect transistor, its control terminal refers to the gate of the field-effect transistor, and the first terminal can be the drain or source of the field-effect transistor, while the corresponding second terminal can be the source or drain of the field-effect transistor.

[0095] When the first transistor Q1 is a P-type MOS transistor (Metal-Oxide-Semiconductor Field-Effect Transistor), the control terminal of the first transistor Q1 refers to the gate of the P-type MOS transistor, the first terminal of the first transistor Q1 is the source of the P-type MOS transistor, and the corresponding second terminal of the first transistor Q1 is the drain of the P-type MOS transistor.

[0096] The communication signals include clock signal SCL and data signal SDA. The communication signals are introduced from the main control circuit (i.e., the microcontroller part). The PWM drive circuit communicates with the main control circuit (i.e., the microcontroller part) through the I2C (Inter-Integrated Circuit) bus protocol.

[0097] In one possible embodiment, see Figure 5 , Figure 5 This is a schematic diagram of a PWM output circuit provided in an embodiment of this application, as shown below. Figure 5 As shown, the PWM output circuit 300 may include: a ninth capacitor C9, a fourth resistor R4, a fifth resistor R5, and a PWM generation chip U2.

[0098] The first terminal A0, the second terminal A1, the third terminal A2, the fourth terminal A3, the fifth terminal A4, the fourteenth terminal VSS, the twenty-third terminal OE#, the twenty-fourth terminal A5, and the twenty-fifth terminal EXTCLK of the PWM generator chip U2 are all grounded.

[0099] The sixth terminal (LED0) of PWM generator chip U2 outputs the first PWM signal SG-1; the seventh terminal (LED1) outputs the second PWM signal SG-2; the eighth terminal (LED2) outputs the third PWM signal SG-3; the ninth terminal (LED3) outputs the fourth PWM signal SG-4; the tenth terminal (LED4) outputs the fifth PWM signal SG-5; the eleventh terminal (LED5) outputs the sixth PWM signal SG-6; the twelfth terminal (LED6) outputs the seventh PWM signal SG-7; the thirteenth terminal (LED7) outputs the eighth PWM signal SG-8; and the fifteenth terminal (LED5) outputs the... LED8 outputs the ninth PWM signal SG-9; LED9, the sixteenth terminal of PWM generator chip U2, outputs the tenth PWM signal SG-10; LED10, the seventeenth terminal of PWM generator chip U2, outputs the eleventh PWM signal SG-11; LED11, the eighteenth terminal of PWM generator chip U2, outputs the twelfth PWM signal SG-12; LED12, the nineteenth terminal of PWM generator chip U2, outputs the thirteenth PWM signal SG-13; LED13, the twentieth terminal of PWM generator chip U2, outputs the fourteenth PWM signal SG-14; LED14, the twenty-first terminal of PWM generator chip U2, outputs the fifteenth PWM signal SG-15; and LED15, the twenty-second terminal of PWM generator chip U2, outputs the sixteenth PWM signal SG-16.

[0100] The 26th terminal of the PWM generator chip U2 is electrically connected to the second terminal of the fifth resistor R5, and the 27th terminal of the PWM generator chip U2 is electrically connected to the second terminal of the fourth resistor R4.

[0101] The 28th terminal VDD of the PWM generator chip U2 is electrically connected to the second terminal of the ninth capacitor C9, the first terminal of the fourth resistor R4, and the first terminal of the fifth resistor R5, respectively, for connecting to the logic power supply VIO.

[0102] The first terminal of the ninth capacitor C9 is grounded.

[0103] The PWM generator chip U2 is used to generate multiple PWM signals to drive external servos or LED light strips.

[0104] In one possible embodiment, the PWM generation chip U2 is a PCA9685.

[0105] The PCA9685 can output 16 PWM signals, namely the first PWM signal SG-1, the second PWM signal SG-2, ..., the sixteenth PWM signal SG-16, with each PWM signal capable of outputting a maximum current of 25mA. The PCA9685 communicates with the microcontroller via the I2C bus protocol, and the microcontroller controls the PCA9685 to output 16 different PWM signals based on the I2C bus.

[0106] The first pin (A0), second pin (A1), third pin (A2), fourth pin (A3), fifth pin (A4), and twenty-fourth pin (A5) of the PCA9685 serve as address selection pins, allowing the I2C address to be set via pull-up or pull-down. The logic power supply (VIO) provides pull-up power to the PCA9685 pins. The twenty-eighth pin (VDD) of the PCA9685 is the power supply pin, used to connect to the logic power supply (VIO) for power supply.

[0107] In one possible embodiment, see Figure 6 , Figure 6 This is a schematic diagram of the structure of an output interface provided in an embodiment of this application, such as... Figure 6 As shown, the output interface 500 includes: a first output plug-in XH1, a second output plug-in XH2, a third output plug-in XH3, a fourth output plug-in XH4, a fifth output plug-in XH5, and a sixth output plug-in XH6.

[0108] The first terminal of the first output plug-in XH1 is connected to the first PWM signal SG-1, the second terminal of the first output plug-in XH1 is connected to the second PWM signal SG-2, the third terminal of the first output plug-in XH1 is connected to the third PWM signal SG-3, the fourth terminal of the first output plug-in XH1 is connected to the fourth PWM signal SG-4, the fifth terminal of the first output plug-in XH1 is connected to the fifth PWM signal SG-5, the sixth terminal of the first output plug-in XH1 is connected to the sixth PWM signal SG-6, the seventh terminal of the first output plug-in XH1 is connected to the seventh PWM signal SG-7, and the eighth terminal of the first output plug-in XH1 is connected to the eighth PWM signal SG-8.

[0109] The first, second, third, fourth, fifth, sixth, seventh, and eighth terminals of the second output plug-in XH2 are all connected to the operating voltage VM.

[0110] The first, second, third, fourth, fifth, sixth, seventh, and eighth terminals of the third output plug-in XH3 are all grounded.

[0111] The first terminal of the fourth output plug-in XH4 is connected to the ninth PWM signal SG-9, the second terminal of the fourth output plug-in XH4 is connected to the tenth PWM signal SG-10, the third terminal of the fourth output plug-in XH4 is connected to the eleventh PWM signal SG-11, the fourth terminal of the fourth output plug-in XH4 is connected to the twelfth PWM signal SG-12, the fifth terminal of the fourth output plug-in XH4 is connected to the thirteenth PWM signal SG-13, the sixth terminal of the fourth output plug-in XH4 is connected to the fourteenth PWM signal SG-14, the seventh terminal of the fourth output plug-in XH4 is connected to the fifteenth PWM signal SG-15, and the eighth terminal of the fourth output plug-in XH4 is connected to the sixteenth PWM signal SG-16.

[0112] The first, second, third, fourth, fifth, sixth, seventh, and eighth terminals of the fifth output plug-in XH5 are all connected to the operating voltage VM.

[0113] The first, second, third, fourth, fifth, sixth, seventh, and eighth terminals of the sixth output plug-in XH6 are all grounded.

[0114] The PWM output circuit in this application outputs 16 PWM signals and transmits them to the first output plug-in XH1 and the fourth output plug-in XH4. Furthermore, for each PWM signal, this application provides an independent power supply. Specifically, the second output plug-in XH2 and the third output plug-in XH3 provide eight independent units corresponding to the eight PWM signals (first PWM signal SG-1, second PWM signal SG-2, ..., eighth PWM signal SG-8); the fifth output plug-in XH5 and the sixth output plug-in XH6 provide eight independent units corresponding to the remaining eight PWM signals (ninth PWM signal SG-9, tenth PWM signal SG-10, ..., sixteenth PWM signal SG-16). For example, the first PWM signal SG-1, the operating voltage VM connected to the first terminal of the second output plug-in XH2, and the ground connected to the first terminal of the third output plug-in XH3 provide PWM control signals and power to an external controlled device (e.g., an external servo motor or LED light strip). Therefore, through the first output plug-in XH1, the second output plug-in XH2, the third output plug-in XH3, the fourth output plug-in XH4, the fifth output plug-in XH5, and the sixth output plug-in XH6, 16 external controlled devices can be controlled simultaneously and independently. Of course, users can also select the number of output PWM signals as needed, and correspondingly select the number of external controlled devices. For example, the PWM output circuit can be controlled to output 8 PWM signals to control 8 external controlled devices.

[0115] This application also provides a substrate, including: the PWM drive circuit as described above.

[0116] This application also provides a development board, including: a substrate and a main control circuit as described above.

[0117] In this embodiment, the main control circuit can be a microcontroller or other microprocessors, such as a 51 microcontroller, ARM, FPGA, or DSP.

[0118] Finally, it should be noted that the above embodiments are merely specific implementations of this application, but the scope of protection of this application is not limited thereto. Any changes or substitutions within the technical scope disclosed in this application should be covered within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A PWM drive circuit, characterized in that, The PWM drive circuit includes: a power supply input circuit, a voltage conversion circuit, a PWM output circuit, a signal input circuit, and an output interface; The power input circuit is electrically connected to the voltage conversion circuit, and the voltage conversion circuit is electrically connected to the output interface; the signal input circuit is electrically connected to the PWM output circuit, and the PWM output circuit is electrically connected to the output interface. The power supply circuit is configured to receive the power supply voltage. The voltage conversion circuit is configured to convert the supply voltage to obtain the operating voltage, and transmit the operating voltage to the output interface; The signal input circuit is configured to connect to logic power and communication signals; The PWM output circuit is configured to output multiple PWM signals based on the received logic power and communication signals, and transmit the multiple PWM signals to the output interface. The output interface is configured to output the multiple PWM signals and the operating voltage corresponding to the multiple PWM signals.

2. The PWM drive circuit according to claim 1, characterized in that, The power access circuit includes: a first power interface, a first diode, and a switch; The first, third, and fourth terminals of the first power interface are all grounded. The second terminal of the first power interface is electrically connected to the positive terminal of the first diode for receiving the power supply voltage. The negative terminal of the first diode is electrically connected to the input terminal of the switch. The output terminal of the switch serves as the output terminal of the power supply circuit, used to output the power supply voltage.

3. The PWM drive circuit according to claim 1, characterized in that, The voltage conversion circuit includes: a first capacitor, a second capacitor, a third capacitor, a fourth capacitor, a fifth capacitor, a sixth capacitor, a seventh capacitor, a first resistor, a second resistor, a second diode, an inductor, a fuse, and a voltage conversion chip; The first terminal of the first capacitor is electrically connected to the first terminal of the second capacitor, the first terminal of the third capacitor, the first terminal of the fourth capacitor, and the seventh terminal of the voltage conversion chip, respectively, for receiving the power supply voltage; The first terminal of the voltage conversion chip is electrically connected to the first terminal of the fifth capacitor, and the second terminal of the fifth capacitor is electrically connected to the eighth terminal of the voltage conversion chip, the negative terminal of the second diode, and the first terminal of the inductor, respectively. The second end of the inductor is electrically connected to the first end of the sixth capacitor, the first end of the seventh capacitor, the first end of the first resistor, and the first end of the fuse, respectively. The second end of the first resistor is electrically connected to the fourth end of the voltage conversion chip and the first end of the second resistor, respectively. The second end of the fuse serves as the output terminal of the voltage conversion circuit, used to output the operating voltage; The second terminal of the first capacitor, the second terminal of the second capacitor, the second terminal of the third capacitor, the second terminal of the fourth capacitor, the positive terminal of the second diode, the second terminal of the sixth capacitor, the second terminal of the seventh capacitor, the second terminal of the second resistor, the sixth terminal of the voltage conversion chip, and the ninth terminal of the voltage conversion chip are all grounded.

4. The PWM drive circuit according to claim 1, characterized in that, The signal input circuit includes: a second power interface, a transistor, a third resistor, and an eighth capacitor; the communication signals include: a clock signal and a data signal; The first terminal of the second power interface is grounded, and the second terminal of the second power interface is connected to the first voltage; The second terminal of the transistor is electrically connected to the second terminal of the second power interface, the first terminal of the transistor is electrically connected to the first terminal of the eighth capacitor, and serves as the first output terminal of the signal input circuit for outputting the logic power supply; the control terminal of the transistor is electrically connected to the first terminal of the third resistor. The third terminal of the second power interface is used to receive the clock signal, and the fourth terminal of the second power interface is used to receive the data signal. The second terminal of the third resistor and the second terminal of the eighth capacitor are both grounded.

5. The PWM drive circuit according to claim 4, characterized in that, The PWM output circuit includes: a ninth capacitor, a fourth resistor, a fifth resistor, and a PWM generation chip; The first, second, third, fourth, fifth, fourteenth, twenty-third, twenty-fourth, and twenty-fifth terminals of the PWM generation chip are all grounded. The sixth terminal of the PWM generation chip outputs a first PWM signal, the seventh terminal of the PWM generation chip outputs a second PWM signal, the eighth terminal of the PWM generation chip outputs a third PWM signal, the ninth terminal of the PWM generation chip outputs a fourth PWM signal, the tenth terminal of the PWM generation chip outputs a fifth PWM signal, the eleventh terminal of the PWM generation chip outputs a sixth PWM signal, the twelfth terminal of the PWM generation chip outputs a seventh PWM signal, the thirteenth terminal of the PWM generation chip outputs an eighth PWM signal, the fifteenth terminal of the PWM generation chip outputs a ninth PWM signal, the sixteenth terminal of the PWM generation chip outputs a tenth PWM signal, the seventeenth terminal of the PWM generation chip outputs an eleventh PWM signal, the eighteenth terminal of the PWM generation chip outputs a twelfth PWM signal, the nineteenth terminal of the PWM generation chip outputs a thirteenth PWM signal, the twentieth terminal of the PWM generation chip outputs a fourteenth PWM signal, the twenty-first terminal of the PWM generation chip outputs a fifteenth PWM signal, and the twenty-second terminal of the PWM generation chip outputs a sixteenth PWM signal. The 26th terminal of the PWM generation chip is electrically connected to the second terminal of the fifth resistor, and the 27th terminal of the PWM generation chip is electrically connected to the second terminal of the fourth resistor; The 28th terminal of the PWM generation chip is electrically connected to the second terminal of the ninth capacitor, the first terminal of the fourth resistor, and the first terminal of the fifth resistor, respectively, for connecting to the logic power supply; The first terminal of the ninth capacitor is grounded.

6. The PWM drive circuit according to claim 5, characterized in that, The output interface includes: a first output plug-in, a second output plug-in, a third output plug-in, a fourth output plug-in, a fifth output plug-in, and a sixth output plug-in; The first terminal of the first output plug is connected to the first PWM signal, the second terminal of the first output plug is connected to the second PWM signal, the third terminal of the first output plug is connected to the third PWM signal, the fourth terminal of the first output plug is connected to the fourth PWM signal, the fifth terminal of the first output plug is connected to the fifth PWM signal, the sixth terminal of the first output plug is connected to the sixth PWM signal, the seventh terminal of the first output plug is connected to the seventh PWM signal, and the eighth terminal of the first output plug is connected to the eighth PWM signal. The first, second, third, fourth, fifth, sixth, seventh, and eighth terminals of the second output plug are all connected to the operating voltage. The first, second, third, fourth, fifth, sixth, seventh, and eighth terminals of the third output plug-in are all grounded. The first terminal of the fourth output plug is connected to the ninth PWM signal, the second terminal of the fourth output plug is connected to the tenth PWM signal, the third terminal of the fourth output plug is connected to the eleventh PWM signal, the fourth terminal of the fourth output plug is connected to the twelfth PWM signal, the fifth terminal of the fourth output plug is connected to the thirteenth PWM signal, the sixth terminal of the fourth output plug is connected to the fourteenth PWM signal, the seventh terminal of the fourth output plug is connected to the fifteenth PWM signal, and the eighth terminal of the fourth output plug is connected to the sixteenth PWM signal. The first, second, third, fourth, fifth, sixth, seventh, and eighth terminals of the fifth output plug are all connected to the operating voltage. The first, second, third, fourth, fifth, sixth, seventh, and eighth terminals of the sixth output plug-in are all grounded.

7. The PWM drive circuit according to claim 3, characterized in that, The second diode is a Schottky diode.

8. The PWM drive circuit according to claim 5, characterized in that, The PWM generation chip is PCA9685.

9. A substrate, characterized in that, include: The PWM drive circuit as described in any one of claims 1-8.

10. A development board, characterized in that, include: The substrate and main control circuit as described in claim 9.

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