Quote:
Originally Posted by Herald1360
Quote:
Originally Posted by Skywave
1. Past experience showed that the temp. coefficient of H.V. Zeners seriously degrades the stabilized voltage;
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To avoid that problem, use a longer string of lower voltage zeners. Distributes the dissipation as well so you can use lower power ones. |
Where is the dividing line between lower and higher voltage zeners where the tempco deteriorates?
Since my last post I recalled that one PSU I built for my HRO HT used 3 zeners (75V ?) to control a MOSFET, thereby reducing the power level and thermal load on the zeners.
B