Bridge rectifier question

You could use a doubler on the secondary side -- but photoflash has been done with flyback converters for decades. Why not use what's tried and true?

--
www.wescottdesign.com

And I just wanted to throw this together using some stuff I had in the junk box. Makes for a fun exercise as well, I guess.

It's just a LM386 "power" amp feeding a surplus audio impedance matching transformer "backwards" through a capacitor. They seem to have a decent amount of bandwidth even up at 20kHz.

--


----Android NewsGroup Reader---- 
http://usenet.sinaapp.com/

Google "Cockcroft-Walton". I'm probably over-summarizing, but the C-W recognizes that there's no reason to stop at doubling if you have enough capacitors and diodes.

I've never built one, but a few people on the group deal with toobs (photomultiplier?) that need low-current HV supplies, and know about them.

--
www.wescottdesign.com

Indeed, I've seen the CW. I'm just wondering if there's a hack I can apply to push it up another factor of 2 with what I've already got without too many modifications to the toplogy, as...um...I did the math wrong when designing it and already have shit soldered to the board...

--


----Android NewsGroup Reader---- 
http://usenet.sinaapp.com/

Sorry, there is no simple way. At least, you need more capacitors and diodes, and it leads to the CW ladder.

--

-TV

C

ut

n

so show us the circuit, there may well be an easy fix but no sense suggesti ng until we know what you've got.

386s still work at 1MHz. Little interstage audio transformers are well out of their depth at 20kHz.

NT

Just a quick sketch:

--


----Android NewsGroup Reader---- 
http://usenet.sinaapp.com/

t DC

us

ng,

thout

been

and

esting until we know what you've got.

out of their depth at 20kHz.

I guess you'll need to go cockroft-walton.

NT

Just bear in mind their V_out is normally woefully short of the ideal.

NT

So if I use the bridge rectifier as part of a two stage CW, in addition to the center tap, that should give me 2x peak to peak, rather than 2x peak, right?

That should work...

--


----Android NewsGroup Reader---- 
http://usenet.sinaapp.com/

too vague. But as said, you'll not get close to the theoretical V_out with a C-W.

NT

Even if it's not continuously loaded?

--


----Android NewsGroup Reader---- 
http://usenet.sinaapp.com/

Offload V_out should climb to theoretical. But give it any load & it nosedives. I'm just saying that expecting more V_out is a common error.

NT

How about a bridge tied load to double the primary drive - you use another amplifier driving the other side of the transformer (that is at present grounded) with the anti-phase signal, or is that too radical?

piglet

Not too radical, I like it. I think I have room to squeeze another '386 on the board.

Not like I don't have enough of them. They're useful for stuff other than audio (like driving servos, and this thing here) have decent GBW, and cost pennies. Less than some electrolytic capacitors for a multi stage CW, even.

--


----Android NewsGroup Reader---- 
http://usenet.sinaapp.com/

Tayda Electronics has ~100k LM386Ls in DIP-8 for 23 cents each in singles.

--


----Android NewsGroup Reader---- 
http://usenet.sinaapp.com/