- I have some home alarm peripherals (motion detectors, glass break sensors) which operate at 12V and draw a nominal current of 20mA when in alarm state.
- I have a Particle Photon (3.3V logic level) which will accept up to 5.6V on its VIN pin.
- I have a 12V @ 2A switching power supply.
Can someone describe to me an efficient circuit which would allow me to power all of the peripherals @ 12V and the Arduino (Particle Photon) at 3.3ishV?
I have on hand an LM7805 linear regulator, which I believe will work, but will be inefficient. I also have on hand a DC-DC step down converter (4.5V-28V IN, 0.8V-20V OUT @ 2A) but I am a novice and don't know how to use it for the scenario described here.