>I have an amp that I have put several 5.6Volt @ 5watt zeners
>in series for cathode bias. They get way too hot with
>about 800ma of current. Can I parallel zeners to divide the
>current without problems with balance between them?
>
Not without potential grief. A more rugged and less costly cathode bias
configuration is a series string of fwd-biased Si diodes. Each diode =
0.7v. // Also, the dissipation rating for zeners is @ 25ºC case temp.,
which is highly unlikely without water cooling. For use in the real
world, divide the diss. rating by 3. Thus, a "5w" /DO-5 case zener is ok
with c. 1.6w. A 5.6V, "5w" zener is good for c. 0.28A, but not 0.892A.
cheers, Doug, N4IJ
>
>
>
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>
- R. L. Measures, a.k.a. Rich..., 805.386.3734,AG6K,
www.vcnet.com/measures.
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