Greetings,
Working on a project requiring both 5V and 3V3 power sources with a load of up to 3 amps; starting with a simple breadboard design but ultimately going to fab some PCBs. Anyone have ideas about the best type of power supply to use?
Our first idea was to start with an AC/DC power supply like this: https://www.jameco.com/webapp/wcs/stores/servlet/Product_10001_10001_210894_-1
But we weren't sure how best to take a 5V supply and convert it into 3V3. Had some 74HC4050 chips lying around and had success using those to do 5V into 3V3 control signals, but it doesn't seem like these chips were built to handle higher amperage load.
We've also seen kits on SparkFun and AdaFruit that offer 5V > 3V3 conversion, but they all seem to use a voltage regulator to dump excess energy as heat to get it down to 3V3, and don't seem built to accommodate a 3 amp load. We're also hoping not to have a dedicated cooling solution built into the product.
We also looked at power supplies which could output both voltages, at the amperages we need:
http://www.powdec.com/pdf/upe65.pdf
But the open chassis design presented some safety considerations (don't want to have folks shocking themselves by accidentally touching it).
What should we do? Get a big 5V supply and find a way to convert it down to 3V3? If so, how? Or go with a dedicated power supply? Any other options?
Thanks for any suggestions.
Christopher