Yet another installment of the diode recovery saga

[Tim Williams]

Complete circuit:
http://webpages.charter.net/dawill/Images/Diode_Recovery_3.gif
http://webpages.charter.net/dawill/Images/DSRPG3_1.jpg
(Low level stuff is breadboarded, ampy stuff is soldered and tight.)

Bleh, two chips to make the double pulse waveform... oh well, a 555 is too
slow. (I didn't even bother trying to test one, so I don't honestly know if
it is. ) CMOS is also finicky with high Z and ESD crappiness, but the
circuit shown seems to work, so long as you don't get your parasites all
over it (a touch's parasitic R and C, that is). The two video transistors
do a reasonable job of amplifying the output for the ZTX dudes, which move
the MOSFET gate by 10V in under 50ns (longer with load).

Output waveform is complementary of the generated pulses, plus some ringing.
At the drain, the Lpulse rings as a result of flyback when the FET is off,
while "output" (sans coupling capacitor) rings when the FET is on.

Waveforms:
http://webpages.charter.net/dawill/Images/DSRPG3_1.jpg
http://webpages.charter.net/dawill/Images/DSRPG3_1.jpg

Tim

 

[Tim Williams]

Derrg, CTRL+V and ENTER to paste a line at a time isn't easy when your
fingers get slurred... I'm goin to sleep. ;o)

Waveforms:

Drain waveform:

http://webpages.charter.net/dawill/Images/DSRPG3_2.jpg
http://webpages.charter.net/dawill/Images/DSRPG3_3.jpg

Gate (*gate*, not before the 10 ohm):
http://webpages.charter.net/dawill/Images/DSRPG3_4.jpg
Dunno what the ~40MHz ringing on the plus peak is... Easy to see miller C
is more effective on turn-off, which it should be with such inductive
loading.

Tim