3 ms·
I'm not sure you need to measure voltage on one of these power banks; they're made to charge phones over micro USB, so they will have a DC-DC transformer giving
by semi-extrinsic 10y ago
I'm not sure you need to measure voltage on one of these power banks; they're made to charge phones over micro USB, so they will have a DC-DC transformer giving 5V all the way down to empty, I believe.
Edit: also, I think the ESP8266 draws about 0.2W on average when it's on. If you have a 10 Wh battery, you can run it for 50 hours in theory. Would you then need deep sleep?