Cheap Varistors or Expensive TVS-diodes?

Vladimir Gurevich


Varistors and suppressors (TVS-diodes) are well-known and widely-used in electronic equipment as components providing voltage surge protection. For very powerful but very short-lasting pulses of the nanosecond range, with steep raising edge (such as HEMP pulses), the suitability of varistors and TVS-diodes is questionable. Since the technical community did not reach any shared vision regarding this point, the author performed its own tests described below.  


varistort; TVS-diode; supressor; HEMP; EMP

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