Synchronous Switchers

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If you're referring to the synchronous switcher power supply (the topic of this thread) I posted the related schematic page for James.

If you're interested in photodiode bootstraps, buy Phil's book.

I doubt that you actually care about either. You're just here to cluck about personalities.

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What in the world is wrong with you? I've posted many schematics of stuff that's in production, including one today.

Senile old fool.

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diode.

Electronic design consists of buying parts and connecting them to one another. Superficially, anybody can do that, and there are a countable number of ways to interconnect N parts having M pins. You can call that paint by numbers, but the numbers are very, very large and the canvass starts out blank. Fact is, some people are very good at this and most people are pretty bad at this, so it's not trivial.

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Not true that the inductor body can capacively couple noise to nearby traces? That's lunatic.

The noise that I'm seeing is mostly below 10 MHz. The wavelength at 10 MHz is 30 meters. The metal box here is about 5x4x1". A 10 MHz EM wave couldn't propagate inside that box.

Sure, but that's not anywhere big enough to cause the spikes I'm seeing. And the spectrum is all wrong to support that as the cause of the noise.

If you can't separate the things that matter from the things that don't, you're in the word salad business.

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Rephrased from is cliche' textbook.

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Sorry, but you're lying... as usual.

I keep my fabulously wonderful circuit design information confidential, but if you'd like a customer name to contact to ask satisfaction with my switcher designs, I'll be more than happy to oblige.

I've been designing switchers since the early '70's, initially for GenRad portable testers, back when you had to understand the whys and hows... way before there was a specialized chip for you to insert in your board and PbN (paint by numbers... on the appnote :-)

Larkin, I've taunted you with a few schematics... asking you to explain how they work. Somehow you always evade such displays of your IGNORANCE.

Did you really graduate from Tulane? I think I'll inquire... I think you lie about everything... a classic narcissistic manic-depressive lying POS >:-}

As for synchronous switchers... I'm presently debugging a Hong Kong customer's problems with an LTC3853. Appears it may be an LTC chip design issue... just promoted from FAE up to corporate!!

What have you pursued lately where you actually knew your ass from a hole in the ground ?:-)

If that's not clear, the answer is zero. ...Jim Thompson

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With a spectrum unit you should be able to connect a sniffer loop on the end of some coax and probe around for the strongest signal..

I have an old service monitor that works well doing this.

Jamie

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I find that an elevated donut coil works well.

Jamie

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Is that one of your own quotes?

Jamie

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Oh, no, we'll take you word for how wonderful you are.

I said here, a while back, that I might go into the picosecond laser driver business. And I did.

Well, 95 picoseconds FWHM.

But make up you mind, you old fool: are you killfiling me or not?

Check one box:

_ / / YES _ / / NO

Here's a switcher I designed in the early 70's, or maybe it was late 60's.

(pic is missing the main inductor, a permalloy powder core toroid.)

It's hysteretic, using an uncompensated uA709 as the comparator, driving a PNP-NPN switch pair. The power NPN runs in emitter follower mode, so it doesn't saturate, so switches fast. This one also charge-pumps a negative supply off the switcher. It's similar to an earlier military design I did for the LHA ships control systems, while I was still a student at Tulane. All my switchers used to run at 22 KHz, because I could hear 20K in those days.

This one doesn't use a tapped inductor. On the MIL one, I put the catch diode on a tap, to reduce the PIV it saw... I couldn't buy a 30 volt power schottky at the time I did that one. There were some interesting consequences to that architecture; do you know what they were?

Wait, wait, let Jim answer.

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You pick your friends and your enemies. I hope you are very, very happy with the one friend that you have here. You are every bit as great a circuit designer as he is.

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Poor baby. I have lots of friends.

And, yes, Fields is excellent at Digital, and I am excellent at Analog.

If you think you're so excellent, why haven't you signed on to my YouTube offer?

Why not? You're an incompetent yellow-bellied lying POS, that's why

Is the manic-depressive cork about to pop ?:-} ...Jim Thompson

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Seems perfectly reasonable.

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I just designed a 75 ohm video driver from discretes because that was as simple and cheaper than a commercial part. But, the requirements kept coming, I kept adding parts, and eventually it made sense to just buy another IC.

(Cool: the part selected was SiGe, clean as a whistle, sings like a bird, three drivers in an so-8, drives 3.1v into 75ohms off a 3.3v supply, and all for under a buck. Who woulda thunkit?)

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It worked better in practice than I expected it to, but then John Devereux discovered it first. So, I credit him ;-).

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Toroids are great. Too bad they're so expensive. This supply's designer chose one of those square units with a ferrite bobbin in a ferrite box, all sealed up with (apparently) ferrite cement.

They're decent, but not perfect.

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Oh, funny, funny! In so many ways. I suppose your analog stuff is buggy hairballs like his async digital atrocities.