On Wed, 28 Jul 1999 12:03:21 -0400 "Tom Rauch" <w8ji@contesting.com>
writes:
>How do you or the others measure recovery time?
Hi Tom,
WIth a bipolar pulse generator (or something equivalent*) that can
drive the diode with low duty cycle pulses at 3X (if I recall the JEDEC
standard correctly) the diodes average rated current in the forward
direction.
You can observe the recovery time on an oscilloscope equipped with a
current probe or alternatively by measuring the voltage across a small
resistor connected in series with the diode..
Incidently, I don't believe that recovery time is an issue in any 60
Hz supply.
73,
Marv WC6W
P.S. --The *
A quick & simple test setup may consist of: a couple of complementary
power FET's (Motorola MTP2955V and MTP3055V) connected as a complementary
follower with their gates connected together and driven, with a small
resistor in series, from almost any old pulse generator. The drains of
the FET's are powered from a bipolar power supply.
The diode under test is connected between the sources of the FET's
(diode anode) and ground (diode cathode). Maximum forward diode current
can be easily set with a resistor in the drain of the FET (3055) which is
connected to the positive supply.
If the duty cycle is kept low (2%), then nothing needs to be heatsinked
and even the power supply can be rather small as long as it has good
hi-frequency bypassing.
*
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