Datasheet

The above shows the Micro USB jack (left), Lipoly JST jack (top left), as well as the 3.3V

regulator and changeover diode (just to the right of the JST jack) and the Lipoly charging

circuitry (to the right of the Reset button). There's also a CHG LED, which will light up while

the battery is charging. This LED might also flicker if the battery is not connected.

Power supplies

You have a lot of power supply options here! We bring out the BAT pin, which is tied to the

lipoly JST connector, as well as USB which is the +5V from USB if connected. We also have

the 3V pin which has the output from the 3.3V regulator. We use a 500mA peak regulator.

While you can get 500mA from it, you can't do it continuously from 5V as it will overheat the

regulator. It's fine for, say, powering an ESP8266 WiFi chip or XBee radio though, since the

current draw is 'spikey' & sporadic.