diode testing

Thread Starter


Joined Nov 24, 2011
hii i basic confused

suppose i applied 230v to single si diode

what diode will be damage?

if yes then what is min voltage supply to diode

what is max voltage of diode


Joined Apr 5, 2008

What is the supposed schematic?
You can NOT give the 230 Volts AC accross the diode directly.
There must be a load in the circuit.



Joined Feb 19, 2009
If you have a diode rated for 500V reverse breakdown.

If you put 250VDC across it reverse biased, no (or very, very low) current will flow (check datasheet for how much).

If you put it forward biased, it would act like a short circuit, and depending on the current rating of the diode, either the diode will explode from sudden heating, or the wire will catch on fire from too much current.

Without more info, those are the two basic outcomes. Reverse biased (with a high enough reverse breakdown voltage), no current flows. Forward biased, once past around 0.6V, diode acts like a short circuit (not exactly, but close enough for this discussion).

If you apply 230VAC across it, the breaker will blow, as well as the diode, it will be alternating between short circuit and blocking.


Joined Feb 19, 2009
i know that so what is max and min value of input voltage on which si diode work safely
Depends on the diode. There are hundreds of thousands to choose from, each has a part number.

Get the datasheet for the part number of the diode you have, and all the info you are looking for will be in there, including reverse breakdown and over current conditions, showing the SOA (Safe Operating Area), without trying to figure all of that out for yourself.

I usually use DataSheets