ac/dc converter

If you are using several different DC voltages inside a unit, (say 5v, 12v, 48v) ignoring efficiency, would it be better to use separate AC/DC power supplies for each voltage or use 1 AC/DC power supply for the highest DC voltage and step down the voltage with DC/DC converters from there?

Hey folks. I’ve been working on a home project involving a low power AC/DC converter based on the power integrations ref (https://www.mouser.com/datasheet/2/328/rdr623-1487555.pdf). There were some minor changes, I added a current limiter to keep to spec, and in addition the circuitry has a...

Hello everyone Please can someone tell me if this IC ( TOP209P ) is the same AS this one ( TYNY275PN) Is it doing the same functions? Can I replace the TOP209P with TYNY275PN ? THANK YOU SO MUCH