Re: TIP50 for HT regulator

In article <4prc84lsgbk0dvoorirkcnrk888gemis2v@xxxxxxx>,
flipper <flipper@xxxxxxxx> wrote:

On Tue, 22 Jul 2008 23:34:17 +0100, Ian Thompson-Bell
<ruffrecords@xxxxxxxxxxx> wrote:

At a local ham fest I picked up 100 of 150V zeners so I thought I would
build myself a stabilised 300V HT supply - not big current, just enough
for my mic pre projects. So, I have been looking at high voltage
transistors and came across the TIP50 which are rated 400/500V. I picked
this oas it the only one whose number I vaguely recognise.

Watch out for SOA and turn on surge into downstream caps. They're good
for about 45mA DC at 300V.

Has anyone used these for HT supplies or what else do you use?

STP2NK60Z is my sort of 'all purpose' N-MOSFET. 600V with built in
gate zener protection and relatively inexpensive. A few pennies less
than a TIP50 but more current and no base drive.

For power supplies I tend to use them as cap multipliers (note that a
cap multiplier is not a reservoir) and screen regulators. I've also
used them as source (cathode) followers when short a triode.

I'm looking for a capacitance multiplier design to replace the inductors
in the power supply for a Single Ended amplifier, are you willing to
share your capacitance multiplier design?


Regards,

John Byrns

--
Regards,

John Byrns

Surf my web pages at, http://fmamradios.com/
.