Equalizing resistors needed for HV diode string?
I guess I should have done a bit more research before I posted my question.
According to the 2005 ARRL Handbook (page 17.9) "shunting resistors are
generally not needed across diodes in series rectifier strings. In fact,
shunt resistors can actually create problems because they can produce a
low-impedance source of damaging current to any diode that may have reached
avalanche potential."
It appears as if the Handbook agrees with you.
John, N9JG
"Chuck Harris" wrote in message
...
[stuff]
The equalization resistors were used with the thought that they would
swamp the leakage current of the diodes in the reverse biased condition,
and make sure that each diode saw only its equal share of voltage.
The truth of the matter is the reverse leakage current will start to
rise rapidly when the diode starts entering its avalanche region, and
the next leakiest diode in the string will start to take over when the
leakiest one starts thinking about avalanching. The string balances,
and protects, itself.
-Chuck
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