Adafruit LC709203F LiPoly / LiIon Fuel Gauge and Battery Monitor - STEMMA JST PH & QT / Qwiic

Product ID: 4712
Qty Discount
1-9 $6.95
10-99 $6.26
100+ $5.56


Low cost Lithium Polymer batteries have revolutionized electronics - they're thin, they're light, they can be regulated down to 3.3V and they're easy to charge. On your phone, there's a little image of a battery cell that tells you the percentage of charge - so you know when you absolutely need to plug it in and when you can stay untethered. The Adafruit LC709203F LiPoly / LiIon Fuel Gauge and Battery Monitor does the same thing. Connect it to your Lipoly or LiIon battery and it will let you know the voltage of the cell, it does the annoying math of decoding the non-linear voltage to get you a valid percentage as well!

Since this nice chip is I2C, it works with any and all microcontroller or microcomputer boards, from the Arduino UNO up to the Raspberry Pi. And you don't have to worry about logic level, as the gauge runs with 3.3V or 5.0V power and logic equally fine. Please note this chip uses I2C clock stretching, on Raspberry Pi Zero/1/2/3 you will need to slow down the I2C port.

To use, connect the 3.7-4.2V Lithium Ion or Polymer battery to one of the JST 2 PH ports (either one). Then use the included JST PH jumper cable to connect to your boost converter, Feather, whatever! Use the I2C interface and our Arduino or CircuitPython/Python library code to set the pack size (this helps tune the calculation) and read the voltage and percentage whenever you like. If you connect a 10K thermistor to the THERM pin you can also use it to read the battery pack temperature - our packs do not come with a built in thermistor but many do.

To get you going fast, we spun up a custom made PCB in the STEMMA QT form factor, making it easy to interface with. The STEMMA QT connectors on either side are compatible with the SparkFun Qwiic I2C connectors. This allows you to make solderless connections between your development board and the LC709203 or to chain it with a wide range of other sensors and accessories using a compatible cableQT Cable is not included, but we have a variety in the shop

Check out our learn guide when schematics, code, diagrams and more!

Play video: New Products 10/6/21 feat. Adafruit VL53L1X Time of Flight Distance Sensor- ~30 to 4000mm-STEMMA QT!

Play video: What is Stemma QT? #adafruit #stemma

Play video: JP’s Product Pick of the Week 11/3/20 LC709203 Battery Gauge @adafruit @johnedgarpark

Play video: New Products 9/2/20 featuring LC709203F LiPoly / LiIon Fuel Gauge and Battery Monitor -STEMMA JST!

Technical Details

Check out our learn guide when schematics, code, diagrams and more!

Revision History:

  • As of March 25, 2024 - We updated this PCB with Adafruit Pinguin to make a lovely and legible silkscreen - you may get the new PCB or the older version with vector fonts - both are identical other than the fancy silkscreen. Additionally, this breakout may come with black or tan STEMMA connectors. They work the same!
  • As of October 6, 2021, this board now has a BGA chip instead of a DFN package. It's the same exact chip, but the DFN version is no longer available. You may get DFN or BGA chip depending on which package we can source during the silicon shortage!

Product Dimensions: 25.4mm x 20.3mm x 7.1mm / 1.0" x 0.8" x 0.3"

Product Weight: 2.4g / 0.1oz

RoHS 2 2011 65 EU Compliant
RoHS 2 2015 863 EU Compliant


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