Re: switched mode power supply

To: tesla-at-poodle.pupman-dot-com
Subject: Re: switched mode power supply
From: Tesla List <tesla-at-stic-dot-net>
Date: Wed, 26 Mar 1997 08:44:50 -0600
Approved: tesla-at-stic-dot-net

Subject: 
        Re: switched mode power supply
  Date: 
        Wed, 26 Mar 1997 14:08:24 +0200 (EET)
  From: 
        Harri Suomalainen <haba-at-cc.hut.fi>
    To: 
        Tesla List <tesla-at-pupman-dot-com>


On Sun, 23 Mar 1997, Tesla List wrote:
> >PWM chip ----- FET ---OOOprimaryOOO---- +ive
> >I found that while say 1A was being fed into the circuit, 4A say
> >(average) was
> >being switched by the FET and 3A was fed back onto the +ve rail via the
> >protection diodes. (with out these diodes overvoltage killed the FET)

You should use eg. clamp winding. Brute force clamping by a diode
backwords in parallel with the primary is not a good idea!

> >I now use Duane Bylands magnifier arrangement:
> >ground----OOOSMPS secondaryOOOOO------OOmagnifier coilOOO-----toriodal

I've found that setup very satisfactory too.

> it's still an idea. if it works it should be sreat, no tonnes of iron
> and
> copper like traditional xfrms.

There are lots of nice things that do work. However, do not expect
wonders with a cw driven coil. My latest prototype was nothing
compared to conventional ones. It definately needed around 500-1000W
to be any fun.. ;)
--
"99% of the pain in the world is due to misunderstanding" -M.
Jarvelainen

Harri.Suomalainen-at-hut.fi - PGP key available by fingering
haba-at-alpha.hut.fi