Pwm control circuit and method meeting aircraft electromagnetic compatibility requirements

Abstract

The application discloses a PWM control circuit and method meeting the electromagnetic compatibility requirement of an airplane. The PWM circuit comprises an input power supply, a potentiometer, a PWM conversion module, resistors R1, R2, R3 and R4. The output end of the input power supply is connected with the first non-common end of the potentiometer and the power supply end of the PWM conversion module, the second non-common end of the potentiometer is connected with the first end of the resistor R1, the second end of the resistor R1 is connected with the ground end, the common end of the potentiometer is connected with the first end of the resistor R2 and the first end of the resistor R3, the second end of the resistor R2 is connected with the ground end, the second end of the resistor R3 is connected with the first end of the resistor R4 and the input analog voltage end of the PWM conversion module, and the second end of the resistor R4 is connected with the ground end. The application has the beneficial effect that based on the simple structure of the pure hardware circuit, the analog voltage of the input power supply is converted into the PWM signal of the exponential type growth, and the frequency, precision and polarity of the PWM signal are controllable.

Description

Technical Field

[0001] This invention relates to PWM control of airborne equipment, and in particular, to a PWM control circuit and method that meets the electromagnetic compatibility requirements of aircraft. Background Technology

[0002] Many airborne devices require PWM control, such as LED-based lighting, display devices, and temperature control equipment. The advantages of PWM control are high output accuracy and minimal impact from chromatic aberration in LED light sources, making it widely used. The disadvantages of PWM control are that it often requires specialized software or complex programmable hardware to implement the PWM control signal output, resulting in high costs, complex hardware circuitry, and reduced reliability.

[0003] Currently, some manufacturers are replacing PWM control with analog voltage control for airborne equipment with simple operating principles. However, analog voltage control is prone to problems such as electromagnetic interference, and it is difficult to achieve exponentially adjustable output, which is detrimental to human-machine interface. Summary of the Invention

[0004] The purpose of this invention is to solve the technical problems in the prior art and to provide a novel PWM control circuit and method that meets the electromagnetic compatibility requirements of aircraft.

[0005] To achieve this objective, the technical solution of the present invention is as follows: a PWM control circuit that meets the electromagnetic compatibility requirements of aircraft, comprising: an input power supply, a potentiometer, a PWM conversion module, resistors R1, R2, R3, and R4; the output terminal of the input power supply is connected to the first non-common terminal of the potentiometer and the power supply terminal of the PWM conversion module, the second non-common terminal of the potentiometer is connected to the first terminal of resistor R1, the second terminal of resistor R1 is grounded, the common terminal of the potentiometer is connected to the first terminal of resistor R2 and the first terminal of resistor R3, the second terminal of resistor R2 is grounded, the second terminal of resistor R3 is connected to the first terminal of resistor R4 and the input analog voltage terminal of the PWM conversion module, the second terminal of resistor R4 is grounded, the GND terminal of the PWM conversion module is grounded, and the PWM output terminal of the PWM conversion module outputs PWM signals; wherein, the PWM conversion module is an analog signal to PWM chip.

[0006] As a preferred solution for a PWM control circuit that meets the electromagnetic compatibility requirements of aircraft, the PWM conversion module further includes: a PWM frequency adjustment terminal; the PWM frequency adjustment terminal is connected to an external VSET voltage signal, and the frequency of the PWM output is adjusted according to the VSET voltage signal.

[0007] As a preferred option for a PWM control circuit that meets the electromagnetic compatibility requirements of aircraft, the PWM conversion module further includes: a PWM accuracy polarity adjustment terminal, which is connected to an external VDIV voltage signal and adjusts the accuracy and / or polarity of the PWM output according to the VDIV voltage signal.

[0008] As a preferred embodiment of the PWM control circuit that meets the electromagnetic compatibility requirements of aircraft, it also includes: a protection and conversion unit, wherein the output terminal of the input power supply is connected to the input terminal of the protection and conversion unit, and the output terminal of the protection and conversion unit is connected to the first non-common terminal of the potentiometer and the power supply terminal of the PWM conversion module, respectively.

[0009] As a preferred solution for a PWM control circuit that meets the electromagnetic compatibility requirements of aircraft, it also includes: resistor R5 and TVS transistor TVS1. The PWM output terminal of the PWM conversion module is connected to the first terminal of resistor R5, the second terminal of resistor R5 is connected to the first terminal of TVS transistor TVS1, and the second terminal of TVS transistor TVS1 is grounded. The second terminal of resistor R5 is used for PWM output.

[0010] This invention also provides a PWM control method that meets aircraft electromagnetic compatibility requirements, including: Provides the aforementioned PWM control circuit that meets aircraft electromagnetic compatibility requirements; and, The duty cycle of the PWM signal is adjusted by changing the output voltage of the potentiometer's common terminal.

[0011] As a preferred solution for PWM control methods that meet aircraft electromagnetic compatibility requirements, the magnitude of the VSET voltage signal is changed to adjust the frequency of the PWM output.

[0012] As a preferred PWM control method that meets the electromagnetic compatibility requirements of aircraft, the magnitude of the VDIV voltage signal is changed to adjust the accuracy and / or polarity of the PWM output.

[0013] As a preferred solution for PWM control methods that meet the electromagnetic compatibility requirements of aircraft, resistors R1 and R2 cause the output PWM to change in a quasi-exponential manner. Adjusting the value of resistor R1 can generate different output change curves.

[0014] As a preferred solution for PWM control methods that meet the electromagnetic compatibility requirements of aircraft, the protection and conversion unit, TVS tube TVS1 and resistor R5 prevent instantaneous high voltage or high current from entering the circuit and damaging it, and prevent high frequency signals from entering the circuit and causing interference.

[0015] Compared with the prior art, the beneficial effects of the present invention are at least as follows: 1. Based on a simple pure hardware circuit, the analog voltage of the input power supply is converted into a quasi-exponentially growing PWM signal, and the frequency, accuracy, and polarity of the PWM signal are controllable, which can be used for the control of airborne equipment such as aircraft lighting; 2. Through the protection and conversion unit, TVS tube, resistor R5, etc., the circuit is protected from damage caused by instantaneous large voltages or large currents generated by static electricity, lightning, etc., thus meeting the electromagnetic compatibility requirements of aircraft; 3. Resistors R1 and R2 make the output PWM signal quasi-exponential (y=a x This invention adapts to meet ergonomic requirements. While ensuring all functional performances, it reduces product design complexity, size, weight, and cost, while improving reliability.

[0016] In addition to the technical problems solved by the present invention, the technical features constituting the technical solutions, and the beneficial effects brought about by the technical features of these technical solutions as described above, other technical problems that the present invention can solve, other technical features contained in the technical solutions, and the beneficial effects brought about by these technical features will be further explained in detail with reference to the accompanying drawings. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of a structure according to an embodiment of the present invention. Detailed Implementation

[0018] The present invention will now be described in further detail with reference to specific embodiments and accompanying drawings. It should be noted that these descriptions of embodiments are intended to aid in understanding the invention and do not constitute a limitation thereof. Furthermore, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0019] Please see Figure 1 The figure shows a PWM control circuit that meets the electromagnetic compatibility requirements of aircraft. It consists of an input power supply, a potentiometer, a PWM conversion module, and resistors R1, R2, R3, and R4.

[0020] The output terminal of the input power supply is connected to the first non-common terminal of the potentiometer and the power supply terminal of the PWM conversion module. The second non-common terminal of the potentiometer is connected to the first terminal of resistor R1. The second terminal of resistor R1 is grounded. The common terminal of the potentiometer is connected to the first terminals of resistors R2 and R3. The second terminal of resistor R2 is grounded. The second terminal of resistor R3 is connected to the first terminal of resistor R4 and the input analog voltage terminal of the PWM conversion module. The second terminal of resistor R4 is grounded. The GND terminal of the PWM conversion module is grounded. The PWM output terminal of the PWM conversion module provides PWM output. The PWM conversion module is an analog signal to PWM chip used to convert the analog signal from the input analog voltage terminal into the corresponding PWM output. GP9303, GP9306, etc., can be used as the PWM conversion module.

[0021] Preferably, the PWM conversion module further includes a PWM frequency adjustment terminal. The PWM frequency adjustment terminal is connected to an external VSET voltage signal. The frequency of the PWM output is adjusted according to the VSET voltage signal.

[0022] Preferably, the PWM conversion module further includes: a PWM accuracy and polarity adjustment terminal. The PWM accuracy and polarity adjustment terminal is connected to an external VDIV voltage signal. The accuracy and / or polarity of the PWM output are adjusted according to the VDIV voltage signal.

[0023] Preferably, it also includes a protection and conversion unit. The output terminal of the input power supply is connected to the input terminal of the protection and conversion unit. The output terminal of the protection and conversion unit is connected to the first non-common terminal of the potentiometer and the power supply terminal of the PWM conversion module, respectively. The protection and conversion unit is used to eliminate damage that may be caused by instantaneous high voltage and high current from static electricity, lightning, etc., and to eliminate interference that may be generated by external high-frequency signals.

[0024] Preferably, it also includes: resistor R5 and TVS transistor TVS1. The PWM output terminal of the PWM conversion module is connected to the first terminal of resistor R5. The second terminal of resistor R5 is connected to the first terminal of TVS transistor TVS1. The second terminal of TVS transistor TVS1 is grounded. The second terminal of resistor R5 serves as the PWM output.

[0025] Among them, resistor R1 is used to adjust the initial angle at which the potentiometer takes effect.

[0026] Among them, resistor R2 is used to make the PWM output change in an exponential manner to meet the requirements of human-machine interaction.

[0027] By changing the output voltage at the common terminal of the potentiometer, the duty cycle of the PWM output can be adjusted.

[0028] Among them, resistors R3 and R4 are used to divide the output voltage of the potentiometer's common terminal.

[0029] Among them, changing V SET The magnitude of the voltage signal can adjust the frequency of the PWM output.

[0030] Among them, changing V DIV The magnitude of the voltage signal can adjust the accuracy and / or polarity of the PWM output.

[0031] Among them, resistor R5 and TVS transistor TVS1 are used to prevent damage to the circuit from instantaneous high voltage or high current such as static electricity and lightning.

[0032] The above description merely illustrates embodiments of the present invention and is quite specific and detailed; however, it should not be construed as limiting the scope of the invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the inventive concept, and these all fall within the scope of protection of the present invention. Therefore, the scope of protection of this invention should be determined by the appended claims.

Claims

1. A PWM control circuit that meets the electromagnetic compatibility requirements of aircraft, characterized in that, include: The system includes an input power supply, a potentiometer, a PWM conversion module, and resistors R1, R2, R3, and R4. The output terminal of the input power supply is connected to the first non-common terminal of the potentiometer and the power supply terminal of the PWM conversion module. The second non-common terminal of the potentiometer is connected to the first terminal of resistor R1, and the second terminal of resistor R1 is grounded. The common terminal of the potentiometer is connected to the first terminals of resistors R2 and R3, and the second terminal of resistor R2 is grounded. The second terminal of resistor R3 is connected to the first terminal of resistor R4 and the analog input voltage terminal of the PWM conversion module, and the second terminal of resistor R4 is grounded. The GND terminal of the PWM conversion module is grounded, and the PWM output terminal of the PWM conversion module provides PWM output. The PWM conversion module is an analog signal to PWM converter chip. It also includes: a protection and conversion unit, the output terminal of the input power supply is connected to the input terminal of the protection and conversion unit, and the output terminal of the protection and conversion unit is connected to the first non-common terminal of the potentiometer and the power supply terminal of the PWM conversion module respectively; It also includes: resistor R5, TVS transistor TVS1, the PWM output terminal of the PWM conversion module is connected to the first terminal of resistor R5, the second terminal of resistor R5 is connected to the first terminal of TVS transistor TVS1, and the second terminal of TVS transistor TVS1 is grounded; wherein, the second terminal of resistor R5 is used for PWM output. Among them, resistor R1 is used to adjust the initial angle at which the potentiometer operates; Among them, resistor R2 is used to make the PWM output change in a quasi-exponential manner to meet the requirements of human-machine interaction; By changing the output voltage at the common terminal of the potentiometer, the duty cycle of the PWM output can be adjusted. Among them, resistors R3 and R4 are used to divide the output voltage of the potentiometer's common terminal.

2. The PWM control circuit conforming to aircraft electromagnetic compatibility requirements according to claim 1, characterized in that, The PWM conversion module further includes: a PWM frequency adjustment terminal; the PWM frequency adjustment terminal is connected to an external V... SET Voltage signal, according to V SET The voltage signal adjusts the frequency of the PWM output.

3. The PWM control circuit conforming to aircraft electromagnetic compatibility requirements according to claim 1, characterized in that, The PWM conversion module further includes: a PWM accuracy polarity adjustment terminal, which is connected to an external V... DIV Voltage signal, according to V DIV The voltage signal adjusts the accuracy and / or polarity of the PWM output.

4. A PWM control method that meets the electromagnetic compatibility requirements of aircraft, characterized in that, include: Provides the PWM control circuit that meets the electromagnetic compatibility requirements of aircraft as described in claim 1; as well as, The duty cycle of the PWM signal is adjusted by changing the output voltage of the potentiometer's common terminal.

5. The PWM control method conforming to aircraft electromagnetic compatibility requirements according to claim 4, characterized in that, The PWM conversion module further includes: a PWM frequency adjustment terminal; the PWM frequency adjustment terminal is connected to an external V... SET Voltage signal, change V SET The magnitude of the voltage signal is used to adjust the frequency of the PWM output.

6. The PWM control method conforming to aircraft electromagnetic compatibility requirements according to claim 4, characterized in that, The PWM conversion module further includes: a PWM accuracy polarity adjustment terminal, which is connected to an external V... DIV Voltage signal, change V DIV The magnitude of the voltage signal is used to adjust the accuracy and / or polarity of the PWM output.

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