Method for improving capacity resistant to strong interference of radar transmitter for MAX 7219

Abstract

The invention relates to a method for improving capacity resistant to strong interference of a radar transmitter for MAX 7219, which is jointly achieved by software time-sequence processing, power supplying source filtering processing, drive current control processing, signal filtering processing, signal impedance processing and the like. A software time sequence processing needle adjusts the time sequence of an input signal of the MAX 7219 and enables the signal to provide the reliable signal time sequence, the power supplying source filtering processing provides a reliable and stable power source to supply power to the MAX 7219, the drive current control processing adjusts output current of the MAX 7219 to reduce the current change rate of drive current, and the signal filtering processing and the signal impedance processing are used for improving the stability of an output series signal. By the adoption of the method, the interference-resistant capacity of the MAX 7219 is improved under the environment of the strong interference of the radar transmitter, and an effective technological approach is provided for achieving a display function with low cost and high reliability under the environment of the radar emitter.

Description

technical field [0001] The invention belongs to improving the anti-interference ability of MAX7219 radar transmitter by using multiple software and hardware processing methods, so that when the radar transmitter works normally, a plurality of digital tubes are stably controlled by the MAX7219 chip to display relevant digital state information of the transmitter. Background technique [0002] When the transmitter is working, a lot of status information needs to be displayed in a certain way so that the operator can understand the real-time working status of the transmitter. Early transmitters generally use analog display, which is not intuitive enough on the one hand, and is subject to observation on the other. The reading error has a great influence, and now more transmitters use digital information display. Since the MAX7219 is a serial input / output common cathode display driver, it can directly drive an 8-bit 7-segment digital display or 64 independent LEDs. , and can be d...

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Problems solved by technology

[0002] When the transmitter is working, a lot of status information needs to be displayed in a certain way so that the operator can understand the real-time working status of the transmitter. Early transmitters generally use analog display, which is not intuitive enough on the one hand, and is subject to observation on the other. The reading error has a great influence, and now more transmitters use digital information display. Since the MAX7219 is a serial input / output common cathode display driver, it can directly drive an 8-bit 7-segment digital display or 64 independent LEDs. , and can be directly connected to the microprocessor, so using MAX7219 to drive multiple digital tubes or multiple LED indicators is a circuit design method that not only saves product cost but also improves design efficiency in radar transmitter status display, but due to The radar transmitter is a high-voltage, high-current device. When it works normally, the output voltage of the high-voltage power supply can reach tens of kilovolts, and the pulse output current can reach several amperes or even a dozen amperes. It is particularly serious for small signal electromagnetic interference. However, the MAX7219 has high EMI requirements because its logic control terminal adopts a non-Schmitt input structure, and its driving current changes greatly instantaneously during operation, which is easy to generate spike interference to the power supply, which in turn affects its own working stability. , because these reasons limit the application of the MAX7219 in radar transmitters

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