Olin Lathrop wrote:
> Bob Blick wrote:
>> Anode to positive supply. It points away from the positive supply
>> toward the base of the transistor.
>> Resistor is chosen for a milliamp or so, if you can afford that much
>> wasted current. So figure 4k3 in a five volt circuit.
>> The amount of current you can absorb is the current through the
>> resistor multiplied by the gain of the transistor, or about 100
>> milliamps with
>> your typical PN2907.
>> If you share one diode and resistor among several clamp transistors
>> then one pin or the total of all can clamp 100 milliamps.
>=20
> Also add a capacitor to ground at the transistor base.  This will let it
> clamp short transients to higher currents.

Cool. I'll add this to my bag of electronic tricks.

Vitaliy
--=20
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