Originally Posted by
Road Fan
Fast switching is not new, so there's no "these days." I was designing switching power supplies in the 1980s and well after. Yes, you can do those things, but at a price. You can build one of anything electronic, but can you make a profitable manufactured product out of it?
true... but things have improved since the 80's.
I recall guys designing most switchers around the common Unitrode 3524(?) controller, and the circuit wouldn't be considered small or fast by today's standards. The mosfets have improved quite a bit, and it amazes me how nicely the manufacturers have integrated the mosfets into the controllers, resulting in very small synchronous switchers that are also rather efficient.
There's also the development of the small microcontrollers that can double as a switcher controller in bike lights.
Depending on what is considered to be "fast switching", circuits have been fast for quite a while, but have gotten much faster. What was typical for the 1980's? 50kHz to 100kHz? A lot of the new little switchers are switching at 1MHz and up.
Amazing stuff, and kept me rather busy when I was helping people fix their EMC problems at work.
Steve in Peoria