How a Switchmode Power Supply Works

[c_hegge]

revised again.

[LongRunner]

Decided to use my recently granted power to do some polishing of this article.

I'll also be inspecting other existing articles and reviews (it's probably as good a thing to do with my spare time as any).

[LongRunner]

I was about to add information on X capacitor discharge ICs and linear regulators used for low-current outputs, but when I went to submit it:

Are you sure you want to do this?

So now I have to start over. WordPress

[LongRunner]

After over another year, I've rewritten what I intended to add last time.

I've also very briefly noted the 'bridge-less' designs but frankly, I have somewhat mixed feelings about the proposition. Moving to synchronous rectification on the secondary side represented a worthwhile gain of 5%+, but doing away with the bridge rectifier saves maybe 1% of the overall power drain at 230V (2% or so at 120V). I don't know exactly how they implement it, but it surely means more complexity - which, by extension, can be said to reduce reliability (if but slightly). I think it's fair to say we're reaching the point of diminishing returns for PSU efficiency improvements; sure, even a 0.5% saving is nice to have, but not if the process of attaining it causes problems elsewhere.

Granted, the other key components grow in complexity too (albeit much of it within large-scale integrated circuits), but at least that's with the prospect of more computing capabilities. (Even if they're wasted on Joe Average…)