Zener diode test with dvom

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Hola Y'all,

My question is there a quick test to check a zener diode to see if its good or bad?? I checked a new one and it measured open in one direction and several meg ohm in the other direction and the zener in question read ~75 ohm in both directions which I suspect is bad. Your comments are welcome.

Regards, Elwood
 
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Should read as a normal diode when forward biased... ie on the diode range on a DVM it will read 0.7 ish meaning 700 mv dropped. 'tother way about and it shouldn't read as general rule for anything over a couple of volts or more but that's useless for testing accurately.

All you need is a battery of higher voltage than the zener and a restor to limit the current. Choose resistor as follows (or even better use a FET as a constant current source)

R= (Vbatt-VZener)/0.010

and measure the voltage across the zener and see if it agrees with the device in question.

Oh yes :) 75 ohms each way... "Oh my" so it is faulty ;)
 
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