PCB EMC design 1）Analysis of signal spectrum A1 = 2τ / T A2 = 0.64 / T f A3 = 0.2 / T tr f2 The shorter the rise (or fall) time, the richer the high frequency components of the signal. （2）Analysis of interference sources ΔI Noise interference Common mode interference and differential mode interference (a)Differential mode radiation （b）common mode radiation Crosstalk When a high frequency current flows through a signal line, the interference voltage will be induced on the signal line adjacent to the PCB board. （3）Wiring design technology ◊ When wiring, make all signal loop areas (especially high-frequency signals and sensitive signal loop areas) as small as possible. ◊ High-speed signal lines should not be crossed over the partition area or over the unrelated reference plane. ◊ In analog circuit and RF circuit designs, as well as in dual panels without a power ground plane, the guard wires are often used to prot...
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