The Cyber-Spy.Com Usenet Archive Feeds Directly
From The Open And Publicly Available Newsgroup
This Group And Thousands Of Others Are Available
On Most IS NNTP News Servers On Port 119.
Cyber-Spy.Com Is NOT Responsible For Any Topic,
Opinions Or Content Posted To This Or Any Other
Newsgroup. This Web Archive Of The Newsgroup And
Posts Are For Informational Purposes Only.
Subject: Re: Problems with MOSFET drivers
Date: Mon, 18 Nov 2002 01:08:05 -0000
NNTP-Posting-Host: modem-228-19-60-62.vip.uk.com (126.96.36.199)
X-Newsreader: Microsoft Outlook Express 5.50.4522.1200
"Mike Poulton" wrote in message
> On 16 Nov 2002, "markp" said:
> > Have you seen this?
> > http://www.richieburnett.co.uk/sstate.html
> Yes. His power switching circuit looks nice, but he doesn't actually
> have the schematic for it up there. The schematic on the site does not
> correspond to the circuit he is using in the final version. He doesn't
> have any sort of active tuning, either. There is some degree of
> frequency adjustment based on the input voltage, but that is open-loop.
> I'd really like to provide some type of closed-loop frequency control.
You could use a microcontroller to form a closed loop. Get it resonating at
roughly the right frequency by stimulating from the CPU using one of its
high speed timers. Use a comparitor to create a digital zero-crossing
detector on the feedback winding, and detect the phase difference between
that and what you're driving it with (all you need is a too slow or too fast
comparison). Fine adjust the output frequency, and repeat. Bingo! This does
Go Back To The Cyber-Spy.Com
Usenet Web Archive Index Of
The sci.electronics.design Newsgroup