Reply-To: "Fred Bartoli"
From: "Fred Bartoli"
Subject: Re: Simple adjustable 0 - 400V regulator, with flaw
Date: Sat, 18 Jan 2003 16:15:12 +0100
X-Newsreader: Microsoft Outlook Express 5.00.2919.5600
Organization: Guest of ProXad - France
NNTP-Posting-Date: 18 Jan 2003 16:14:10 MET
"Fred Bartoli" a
écrit dans le message news: email@example.com...
> "Winfield Hill" a écrit dans le message news:
> > The Intersil HIP5600 is an adjustable three-terminal regulator
> > that can be thought of as a 500V version of the LM317. I've
> > used it in many of my lab instrument designs and found it to
> > be reliable and, like the LM317, an elegant design simplifier.
> > For example, here's a simple adjustable 0 to 400V regulator,
> > with a fixed-voltage feature.
> > . +480V ___ HIP5600
> > . ---| |---+---+-----------(O) HV out
> > . |___| | |
> > . | | 1.5k
> > . | | | adjust, 0 - 400V
> > . '---- | --+----o->o--------,
> > . | o--, |
> > . 10uF === 300V | 500k
> > . 450V | fixed | pot
> > . | 380k |
> > . ______|______________|_____|____
> > . gnd
> > The switch allows one to select a fixed 300V output, or to
> > adjust the voltage to any value between 1.2 and 400 volts.
> > But this circuit has one potential problem that can cause
> > a component failure. As a design quiz, tell us what the
> > problem is, and find a solution that doesn't significantly
> > affect any of the circuit's functionality. Hint, the '5600
> > isn't the vulnerable part.
> > Thanks,
> > - Win
> Add some Al and mylar to have enough time :-)
Or 2x200V zener diodes in case the pot fails.