>Hi Rich,
>
>Re: Power zener surge current ratings....
>
>You normally won't find the surge rating for a zener on a data sheet, since
>a single-die zener isn't normally tested under surge conditions, it's
>characterized for DC; e.g., the 1N3306B is rated 6.9Adc zener current at
>stud temperatures up to 75 degrees C. However, the real surge rating is
>found when the same die is rated as a transient voltage suppressor, such as
>the Microsemi 15KE7.5A, which uses the same silicon zener die as the 1N3306B
>but is characterized not for DC use, but as a TVS. That part is rated 15kWp
>based on an 8/20uS pulse waveform, which translates per the curve to a
>1,500Apk rating. Same die, same device, just tested differently.
Thanks, Steve. However the zeners used by amp mfgs reportedly have a
high failure rate and none of them have adjustable Vz. A string of fwd
biased Si diodes does the job for this application.
>
- R. L. Measures, a.k.a. Rich..., 805.386.3734,AG6K,
www.vcnet.com/measures.
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