I am building an ESP8266 device that uses RFID but need to conserve battery power.
The ESP is a Wemos D1 Mini and the RFID module is a RC522 (still waiting for it to arrive), which needs 3.3 V. I'm powering the ESP with a battery shield and 3.3 V.
But I don't want to connect the RFID module directly to the battery shield because it will be sucking voltage constantly. Instead, I want to be able to control its power using the ESP.
So I thought the easiest would be simply to connect the RC522's 3v3 line to one of the ESP's available GPIO pins, set it to output, and when I need RFID, set the GPIO pin high, to turn on the RFID module.
Is this an acceptable solution, or do I need to wire in a transistor and capacitor somewhere?
it will be sucking voltage constantly
.... not voltage ....current
orpower
– jsotola Jul 19 '18 at 1:16