From: "Jan Wagner"
Subject: Re: low loss transformer availability?
Date: Sun, 5 Jan 2003 18:38:31 +0200
Organization: Helsinki Television
NNTP-Posting-Date: 5 Jan 2003 16:33:23 GMT
X-Newsreader: Microsoft Outlook Express 6.00.2720.3000
"Smile, it can only get WORSE" wrote in message
> RL and others....
> OK, I read all the comments and thank you all.
> Here's a reply to all the comments posted previously, forgive me for
> not posting separate replies.
> I need a transformer that has a high impedance input-so that it
> doesn't draw much current from the driver source when there is only a
> small load current being extracted from the secondary. I was hoping to
> operate at 3 mhz because it's easier to make a high impedance primary
> when the frequency is higher and 3 mhz is fairly easy to work with.
> In reality, I might be able to go down to 100 kilohertz or as high as
> 5 mhz.
> I need 12 V AC RMS in..... and (about) 120 V AC RMS out.
And a charge pump, voltage multiplier, or high efficiency boost converter is
out of the question?
But the main question - what type of load is it?
Does it really have to be AC? "AC" meaning sine, square, sawtooth, ...?
Your load requirements seem to be really non-critical because you said it
works from 100 kHz to 5 MHz? A very small boost converter as in the second
www link given above could be your solution, but only if DC output is ok.
If 100kHz is ok and it _must_ be AC then you should consider targeting your
transformer for that 100kHz frequency - much easier than for 3 MHz or 5 MHz,
given your low power & low loss specs.