Help with circuit for microcontroller based power supply

[irshad9in]

Hey guys, I would like to buid an IOT type of power supply controlled by a microcontroller, that could output :

1. 3.3V (Current Controllable)
2. 5V (Current controllable)
3. A boost converter to achieve voltages upto 12V

The circuit should run off from a a standard wall wart USB adapter that may supply 5V at 2A. It has been hard to find any suitable reference power supply design for this use-case. Please update this post with the ideas you may have and any exisiting reference designs, if possible. Thanks in advance.
The first idea I had is to use the boost converter to produce 12 V from the wall wart 5V and then use this to create the necessary 5V and 3.3V. The most useful resource till date I looked into is from tuxgraphics. If you have further ideas of improvements or reference dsigns..please share here.

 

[KlausST]

Hi,

If you want to use three times the same circuit, then look for SEPIC.

Many smps controller IC manufacturers have interactive selection guides at their internet pages.
Datasheets with schematics and application notes.

Klaus