On Sat, 10 Oct 2009 16:37:51 -0500, krw wrote:

On Sat, 10 Oct 2009 10:33:43 -0700, Archimedes' Lever
wrote:

On Fri, 9 Oct 2009 14:33:42 -0700 (PDT), "
wrote:


Filter capacitors and inductors too. It's not uncommon for switching
power supplies to be above 1MHz, also to keep the size of components
(and costs) small.

...and transformers get *very* big at DC.


I want a citation that switchers are commonly running at and above
1MHz.

AlwaysWrong strikes again.

One example, at random: LTC3555 three buck regulators, each 2.25MHz.

http://www.linear.com/pc/productDeta...C1773,P3 7856

NONE of ours did.

I'd be surprised if yours *worked*, DimBulb.

Our power supply company survived after 911, a time when several
hundred other companies failed.

Those supplies were and are in a lot of the things you use because we
were OEMers for hundreds of companies as well.

You're an idiot, KeithTard.

Also, regardless of what the max frequency a regulator *can* operate
at, that does not mean that they get designed to operate there.

Folks engineer a supply on the bench, and the final most efficient
frequency a design runs at my not be the original estimation.
I would not expect you to get it though.

No... NONE of our units ran that fast. Magnetics tends to get
inefficient at passing power at too high a frequency. Our HV supplies
may have had switcher front ends, but they typically had a transformer
driven final feeding the multiplier stage. Most all were 100kHz.