Features:

  • 3.2A switch mode single cell lithium battery charge IC
  • 3.5A switch mode USB boost IC, 2 USB ports [8A internal switch: 3.5A output over full lithium battery voltage range 3.0 - 4.2V!]
  • Dynamic power management: When input is connected a USB load is prioritized over charging. When input is sufficiently rated both the load and battery can be powered. When an input is insufficiently rated for USB load, the battery will go into load supplement mode.
  • Selectable 5.1V or 5.5V output
  • On-board programmable Atmega328p
  • On-board fuel gauge
  • Automatic USB adapter current rating detection
  • Adaptive fastcharge detection (9V or 12V)
  • BC1.2 USB controller IC on output
  • 3 addressable RGB leds
  • 1 tactile button
  • 3V Serial communication [Pi and Arduino compatible]
  • Fully featured library for Arduino IDE, a few lines of code will setup your powerbank

Program (using serial or ISP programmer or even an Arduino):

  • Max input current (500mA up to 3250mA)
  • Max charge current (500mA up to 5000mA! Anything over 3A will require active cooling)
  • USB boost output voltage: 5.1V or 5.5V
  • Independently enable/disable charger IC
  • Independently enable/disable USB boost output
  • Deepsleep shutdown (45uA sleep)
  • Interrupt wake on button, USB load or INT pin
  • 3 RGB WS2812b leds, individually addressable
  • Slide switch functionality, 3 positions
  • Tactile button functionality

Digitally monitor:

  • Input current
  • Charge current
  • Output current
  • Input voltage
  • Charging status (precharge, fastcharge, charging done, not charging)
  • USB Input type (SDP, CDP, DCP, or High voltage adaptive fastcharge @ 9 or 12V)
  • Battery percentage
  • Battery voltage
  • Battery temperature
  • Slide switch position
  • Button press

Safety:

  • Reverse polarity battery protection
  • Automatically detect current rating USB input
  • Undervoltage battery FET disconnect
  • Overvoltage battery FET disconnect
  • Boost IC under voltage lockout
  • Battery temperature monitor, battery will disconnect on NTC over- and undertemp
  • USB output overcurrent protection
  • Thermal shutdown protection for both charge and boost IC’s
  • Watchdog timer

Broken out I/O and power:

  • SDA/SCL, attach 3V logic compatible I2C devices (OLED 0.96 display succesfully tested!)
  • Hardware Serial pins
  • Interrupt pin internally connected to button and charger IC interrupts
  • 3V linear regulator pin
  • 5V output voltage pin
  • Two GND pins
  • ISP connector
  • Reset pin with timing capacitor (connect Serial programmer with auto reset, user will need to burn Arduino bootloader through ISP)