Just got my first one of these installed. Stupid holidays always getting in the way of the fun stuff!
Wired it into the USB adapter for a HEMv1, stuck it in the battery compartment of the Iris keypad, and it works great so far!
Setting the potentiometer is a pain, very very sensitive but got it to 3.1xx volts, as close as I could come to the nominal 3.26v I get from my batteries. Haven’t soldered it all together yet, but it’s running fine and not heating up at all. Input voltage from the USB adapter is actually higher than I thought, a bit over 6.2v vs the roughly 5v I expected.
Not sure if I mentioned this above, but anyone that wants to do this, remember to put the voltage regulator as close to the device it’s going to power as possible. Since you are dropping voltage, you want the strongest signal you can get from the power source, and losses at lower voltages like this can happen quick, so the 1.2v or 3.2v most battery operated devices use, will loose FAR quicker if you voltage drop at the power supply vs the device.
I used a single pair from a solid core CAT6 for the wires, couldn’t find my stash of garage door opener wire…but it worked great!