Research On Electromagnetic Compatibility Of Printed Circuit Board Of Circuit Breaker Control Circuit

With the rapid development of electronic devices,greater demands of printed circuit board are being placed on people,high speed in digital circuit and high sensitivity in analog circuit occur on the same printed circuit board,the scope of application of the hybrid circuit module is more and more widely.This kind of high speed,high integration trend has brought many new problems for the hardware design of electronic circuit,the electromagnetic compatibility problem is particularly significant,for this reason,the problem of electromagnetic compatibility has attracted more and more attention.The circuit breaker's control circuit has been designed in this thesis,and take this printed circuit board as an example,analysis of electromagnetic compatibility of the circuit board.Then by using Cadence software,modeling and simulate the printed circuit board,get the circuit board space near field intensity distribution and near field intensity distribution,through analyzing the field distribution map,sensitive frequency can be obtained by the circuit board,and the strength and coupling condition around the field circuit board can be visually seen.By applying the harassment for the circuit board,get the voltage of sensitive device pins,and after the inverse calculation,get the maximum tolerance voltage of field circuit board.Compare the circuit board of the space electric field strength and the maximum tolerance the field of surroundings,quickly determine the working state of the circuit board.According to the circuit board space near electromagnetic field intensity distribution,analyze the situation from the two aspects of capacitive interference and inductive interference,put forward the modification scheme of PCB layout and wiring,and by adding decoupling capacitors and voltage sensitive resistors,the circuit board is further improved.At the same time,according to adding the shield to the circuit board,the electromagnetic compatibility and anti-interference ability of the circuit board has been optimized.Finally,the effects of two different circuit boards on the immunity of the circuit board has been compared,and the effectiveness of the method is verified by simulation.