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What is High Frequency Circuit PCB?
2020-09-01
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Author:Holia      Share

What is High Frequency Circuit?


In a digital circuit, whether it is a high-frequency circuit depends on the rising and falling edges of the signal, rather than the frequency of the signal.


Formula: F2 = 1 / (TR × π), TR is the rising / falling delay time of signal.


If F2 > 100MHz, it should be considered according to the high-frequency circuit, and the following conditions must be designed according to the high-frequency rules:

  1. The system clock frequency exceeds 50MHz

  2. The device with rise / fall time less than 5 ns is used

  3. Digital / analog hybrid circuit


The rise / fall time and wiring length of logic devices limit the rise / fall time tr component F2 = 1 / Fmax = 10 * distance (microstrip) line distance (microstrip line)πTr   F2  



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