ESP8266 Community Forum

I have a box of old mobile phone chargers that I held onto for future projects. I was wondering if ESP-based projects would work. Without listing specifics of each unit, they are generally 5v mini usb but a couple are different connectors (1 is 5.9v). Most are fairly low current (50mA-750mA).

ESP is supposed to be ideal for low power battery use, so I was figuring unless a component added to the project was picky, these would work.

The average current is low. But use a 3.3 volt regulator that is rated for 500 mA. If you are using a board that has a regulator then you of course you don't need to worry about that. The ESP8266 can draw 400 mA for a short period on startup when it is going through a calibration.

I am planning on using D1 mini's which have micro usb inputs. I could also connect to Vin instead since the connector on my power supplies generally won't match. If the ESP needs 400mA 3.3v, how would I know what 5 current would suffice?

That board uses a linear regulator from 5V to 3.3V so the current requirement from 5V is just about the same e as needed for 3.3V.

There is a little extra current needed for the on-board USN/serial interface but 500mA should be fine. As mentioned the average current draw will be significantly less.