The TP4056 1A Lithium Battery Charger is the absolute industry standard for safely charging single-cell 3.7V Lithium-Ion and Lithium-Polymer (LiPo) batteries. Utilizing a highly precise constant-current/constant-voltage (CC/CV) charging profile, this tiny board ensures your cells are charged quickly and safely to their maximum capacity of 4.2V without the risk of dangerous overcharging.

This specific variant is the “Unprotected” model. It is designed purely as a charging circuit and does not include the secondary DW01 battery protection IC found on larger boards. This makes it exceptionally small and cost-effective, but it means that the battery you are charging must have its own internal protection circuit (PCM/BMS), or you must monitor the battery manually to prevent it from deep-discharging below 3.0V when connected to a load.

Key Features & Functional Advantages:

• Micro USB Input: Conveniently power the charger using any standard micro USB smartphone cable and a 5V wall adapter, or solder directly to the IN+ and IN- pads if using a custom 5V power supply.

• 1A Fast Charging: Delivers up to 1000mA of charging current by default, capable of replenishing a standard 18650 battery in just a few hours.

• Programmable Charge Rate: The default 1A charge rate can be easily lowered to safely charge smaller capacity batteries (like 200mAh or 500mAh LiPos) by replacing the onboard Rprog (R3) surface-mount resistor.

• CC/CV Charging Profile: Safely ramps up current when the battery is low, and seamlessly switches to a constant voltage trickle-charge as the cell approaches 4.2V, maximizing battery health.

• Visual Status Indicators: Features two onboard surface-mount LEDs. A Red LED indicates active charging, while a Green (or Blue, depending on the manufacturer) LED illuminates the moment the battery reaches full capacity.

Perfect For:

• Retrofitting Rechargeability: An excellent, tiny module for upgrading vintage electronics, toys, or flashlights to run on modern, rechargeable protected 18650 or LiPo batteries.

• Workbench Charging Stations: Easily wire several of these modules in parallel (each with their own battery) to create a multi-bay custom charging station for your drone or RC batteries.

• Replacing Broken USB Ports: A cheap and easy permanent fix for Bluetooth speakers or headphones where the original charging port has been ripped off the main circuit board.

• Prototyping: A staple for any electronics hobbyist needing a quick, reliable way to top off batteries during the design phase of a project.

Technical Specifications:

• Charging IC: TP4056

• Input Voltage: 4.5V to 5.5V DC

• Full Charge Voltage: 4.2V ( 1.5% accuracy)

• Maximum Charging Current: 1000mA (1A)

• Input Interface: Micro USB (Female)

• Over-Discharge Protection: None (Requires a battery with an internal protection circuit)

• Operating Temperature: -10C to +85C

• Dimensions: Approximately 22 mm x 17 mm

• Connection Pads: BAT+ (Battery Positive) and BAT- (Battery Negative)