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From: Bill Sloman <bill.sloman@ieee.org>
Newsgroups: sci.electronics.design
Subject: Re: 1KV buck converter
Date: Tue, 27 May 2025 14:16:04 +1000
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On 27/05/2025 10:39 am, Hul Tytus wrote:
> Bill - there was some talk here about a power supply I was working on. It used a pnp transistor
> driven by 2 capacitors and a diode to switch a solenoid style inductor. Efficiency was about 80%. This
> was two or three years ago. Initial starting powrer can be a puzzler.

Hi Hul - getting Baxandall style inverters to start-up cleanly can be a 
problem. The amplitude can overshoot. The 1959 original would "squeg" is 
the feed inductor was too big, and you used bipolar transistor switches, 
which is something I've never been able to simulate. MOSFET switches 
apparently aren't susceptible to this problem.

-- 
Bill Sloman, Sydney