3.1A powerbank, 2 x BC1.2 ports, Arduino IDE configurable, 4 RGB LEDS

A small configurable 3.1A lithium battery powerbank, 2 x BC1.2 power ports, 4 RGB status LEDs double as a powerful torch. Arduino ISP programmable. Actually handles amperage without dropping below 5V output!

  • BQ25895 charge / boost IC
  • 3.1A combined output current
  • 2 x USB type-A
  • Quickcharge 2.0 micro USB input, max 3.25A
  • Atmega328P-MU microcontroller
  • Arduino IDE programmable (ISP pins broken out)
  • MAX17043 state-of-charge IC
  • Deepsleep mode
  • 4 x RGB WS2812b leds
  • Thermistor pins
  • 6A fuse protection
  • ESD protection
  • Tactile switch power (on/off or function)
  • Serial out (debug)

A small powerbank which uses bq25895’s On The Go 5.3V 3.1A output to power two USB ports + Quickcharge 2.0 high voltage charging. I added an ATMEGA328P-MU to handle all bq’s I2c communications and control 4 WS2812b RGB leds. Program the LEDs using the ISP pins to display animations based on input current, cell voltage, state of charge, program a torch etc. A MAX17043G is placed in parallel with the battery to measure state of charge, also configurable by I2c.

A few caveats: The microcontroller is powered by OTG so, when bq25895 is in sleep mode, all power is lost. You can only wake the device using the QON pin (connected to the button). A new version of this board is in the making, which will add an extra boost converter (simultaneous charging and boosting with powerpath management), a usb type C  port (replaces one type A) and always on LDO (ability to wake system on usb attach, detach).

Preliminary powerbank code