Datasheet

Power Management
Battery + USB Power
We wanted to make the Feather HUZZAH easy to power both when connected to a computer as well as via battery.
There's two ways to power a Feather. You can connect with a MicroUSB cable (just plug into the jack) and the Feather
will regulate the 5V USB down to 3.3V. You can also connect a 4.2/3.7V Lithium Polymer (Lipo/Lipoly) or Lithium Ion
(LiIon) battery to the JST jack. This will let the Feather run on a rechargable battery. When the USB power is powered,
it will automatically switch over to USB for power, as well as start charging the battery (if attached) at 100mA. This
happens 'hotswap' style so you can always keep the LiPoly connected as a 'backup' power that will only get used
when USB power is lost.
Don't power the Huzzah ESP8266 with a CanaKit 5V power supply, these power supplies have been
destroying the CP2104 chip.
The JST connector polarity is matched to Adafruit LiPoly batteries. Using wrong polarity batteries can destroy
your Feather
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