Some precautions for using high frequency microwave circuit boards?
Release time:
2022-08-18 10:32
Source:
high frequency microwave circuit boardIt refers to the special circuit board with high electromagnetic frequency. In fact, it is mainly used for high frequency (frequency greater300MHZor wavelength less1m) with microwave (frequency greater3GHZor wavelength less0.1m) in the fieldPCBHere are some precautions for using high-frequency microwave circuit boards?
high frequency microwave circuit boardWhen using, we need to know that if the power tube is not connected, it is only during the output test, then it must be connected to the collector and emitter of the power tube.(or drain and source)The two points are short-circuited. Because at this time, if his collector or drain is suspended, then the driver or driver board will think that the power tube is in a short-circuit state and start the internal protection mechanism. At this time, you will see the protection signal waveform output by the driver, and whether its waveform shape or period is the same as the inputPWMThe signal is completely different.IGBTThe main problem to be solved in the application is how to achieve perfect in the case of overcurrent, short circuit, overvoltage, etc.IGBTProtection. In addition, since the overcurrent fault of the high-frequency microwave circuit board generally takes a little longer to overheat the power supply, its protection is solved by the main control board. Therefore, when running, you will find that overvoltage usually occurs inIGBTWhen closed. LargerDI/DTA higher voltage is generated on the parasitic inductor, which requires clamping with a snubber circuit, or a lower turn-off rate. Then the short-circuit fault of the high-frequency microwave circuit board will generate a large current instantaneously after it occurs, and it will soon be damaged.IGBTOvercurrent protection of the main control board is too late and must be protected by the drive circuit or driver immediately.
When using high-frequency microwave circuit boards, it should be noted that when wiring, the middle inner plane is used as a power supply and ground layer, which can effectively reduce parasitic inductance, shorten the length of signal lines, and reduce cross interference between signals. Generally speaking, the noise of the four-layer board is lower than that of the two-layer board20dB. In addition, it should be noted that in high-frequency circuit boards (microwaveRFIn the design of the board), the smaller the number of through holes, the better. Or in the design of high-frequency circuit boards (microwave radio frequency boards), the shorter the total length of the wiring, the better, and the shorter the parallel spacing between the two wires. InPCBIn the design of (high-frequency circuit board), the interference between signals can be reduced by adding grounding copper foil. When wiring a high-frequency microwave circuit board, the decoupling capacitor is bridged at the power supply terminal of the integrated circuit. Its signal routing cannot generate loops and must be arranged in a daisy chain. Another important point is that during the wiring process, when connecting digital ground and analog ground, you need to connect a high-frequency choke device, usually a high-frequency ferrite bead through the center hole. In fact, during the formulation of high-frequency microwave circuit boards, the direction of interlayer wiring should be vertical, that is, the top layer is horizontal and the bottom layer is vertical to reduce the impact of signals.
The above article content is Xiaobian for everyone to introduce about the usehigh frequency microwave circuit boardIf you are curious, please come and have a look. I believe it will not disappoint you. That's all for today's content. I hope I can help you.
Recommend Articles
Lantern Festival, light up the heart of the lamp-with Jin Shengda circuit to spend the festival
The Lantern Festival, also known as "Shangyuan Festival" or "Lantern Festival", is one of the traditional festivals of the Chinese nation. On this day, people enjoy lanterns, guess lantern riddles, eat yuanxiao, and share reunion and joy. In this warm and peaceful festival, all the staff of Jinshengda circuit extend their most sincere wishes to you and wish you and your family a happy Lantern Festival and a happy family!
Jin Shengda Circuit gives you a New Year greeting!
As the New Year bell is about to ring, all employees of Jinshengda Circuit extend their most sincere New Year greetings to you!
Welcome New Year's Day | Jin Shengda Circuit
New Year's Day is a new beginning and a symbol of hope. In the past year, we have experienced countless challenges and opportunities together. It is these challenges and opportunities that have strengthened our pace and made us more aware of the importance of unity, cooperation and innovation.
Service Hotline (7*24 hours)
Customer Service:service@jsdpcb.cn
Business Sales:sales@jsdpcb.cn
Marketing:marketing@jsdpcb.cn
TikTok
WeChat Public Number
Copyright© Shenzhen JSD PCB Technology Co., Ltd., 2024
