USB LiIon/LiPoly charger - v1.2

This Lithium Ion and Lithium Polymer Battery Charger is based on the MCP73833 chip, designed for charging single 3.7V/4.2V Li-ion or LiPo batteries via a USB mini-B connection. It provides an efficient three-stage charging process: a preconditioning charge, followed by a constant-current fast charge, and finishing with a constant-voltage trickle charge to keep your battery topped-up.

Key Features:

• Adjustable Fast-Charge Current:

  • The default fast-charge current is 500mA, but it can be easily adjusted from 100mA to 1000mA by soldering a through-hole resistor on-board.

• Three LED Indicators:

  • Power LED: Lights up when the charger is powered.
  • Charging LED: Indicates when charging is in progress.
  • Complete LED: Shows when charging is finished.

• Separate JST Connectors:

  • Keep the battery connected while passing power through the additional JST connector without removing the battery.

• Thermistor Support:

  • The chip supports a 10K NTC thermistor (included as a plain 10K resistor), which can be replaced with the thermistor for temperature monitoring when using high charge rates.

Specifications:

• Input: 5V via mini-B USB connector.
• For Charging: Single 3.7V/4.2V Lithium Ion/Lithium Polymer Batteries (not for older 3.6V/4.1V cells).
• Adjustable Current: 500mA (default), adjustable from 100mA to 1000mA.
• Breakouts: 0.1" (2.54mm) for battery, DC input, and status LEDs.

What's Included:

• Assembled and Tested Charger Board.
• Free 2-Pin JST Cable.
• Batteries and USB Cable not Included.

Perfect for your DIY electronics projects, this charger is designed for safe and efficient battery charging with easy-to-use functionality.