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Diode recovery time question?

Hello,


I have a little question about regular diodes.

I know that when we connect a high frequency signal to a diode (in series with a resistor), that diode won't fully cut off the current as soon as the voltage becomes negative. (see picture)

But what happens if we're not working on high frequencies, but we do create the same negative flank like in the picture?
(so just the same as half the cycle of that high frequency signal, but we only do it once?)

will the diode still have that same recovery time if the signal goes from positive to negative Very quickly?

if that is so, that means that every regular diode fails at blocking a negative voltage pulse?


Greetings,

Electorials

Picture of Diode recovery time question?
iceng3 years ago
That inverse current peak is largely dependent on how fast the voltage reverses.

A diode can be considered as a capacitor for the recovery of PN junction charge carriers.

So, as the frequency goes down, even though the reverse voltage is the same magnitude the IRR (PEAK)  is less because the transition time is
slower.

A
Electorials (author)  iceng3 years ago
Oh yes, thanks!
Yes but its completely negligible at low rates of change of current.
Electorials (author)  steveastrouk3 years ago
ok, and is the negative induction voltage of a coil a low or a fast current change?
Depends on the size of the coil ! Typically, for the sort of circuits you're likely to build, low.
Electorials (author)  steveastrouk3 years ago
Ok, thank you!