The TP4056 Lithium Ion Battery Charger with Battery Protection – Mini USB is a compact and efficient module for charging a single-cell (1S) 3.7V lithium-ion or lithium-polymer battery from a 5V USB power source. The “with Battery Protection” variant incorporates additional circuitry, typically the DW01A integrated circuit, which provides protection against over-discharge, over-current, and short-circuit events.Features:Charging method: The module uses a constant-current/constant-voltage (CC/CV) linear charging algorithm to safely and effectively charge a single lithium cell.Charge current: The default charge current is set to 1 Amp (1A) but can be adjusted to a lower rate by replacing a resistor on the board, making it suitable for batteries of different capacities.Input power: You can supply 5V DC power via the mini USB port or directly to the “IN ” and “IN-” solder pads on the module.LED indicators: Two onboard LEDs indicate the charging status. A red LED illuminates while the battery is charging, and a green or blue LED indicates a full charge.Protection features: On models with battery protection, the module includes a DW01A chip and a dual MOSFET to monitor and protect the battery.Over-discharge protection: Shuts off the output when the battery voltage drops below a specified threshold, typically around 2.5V, to prevent damage.Over-current protection: Prevents the battery from being discharged at an unsafe rate by cutting the current if it exceeds a certain limit (e.g., 3A).Short-circuit protection: The output is shut off if a short-circuit is detected.How to use the module:Connect the input power: Plug a mini USB cable into the module or supply 5V DC power to the “IN ” and “IN-” pads.Connect the battery: Solder the positive wire from your single lithium battery to the “B ” pad and the negative wire to the “B-” pad on the module. Ensure correct polarity to avoid damaging the module.Connect a load (optional): To power a project or load, connect it to the “OUT ” and “OUT-” pads. For models without the DW01A protection circuit, you would connect the load directly to the B /B- terminals.Important: Avoid running a load while the battery is charging. Power should be taken from the output only after the 5V input has been disconnected.Monitor charging status: The red LED will turn on when charging begins. When the battery is full, the charging cycle will terminate automatically, and the green/blue LED will turn on.Safety considerations:Reverse polarity: The TP4056 IC itself does not have reverse polarity protection. Connecting the battery incorrectly will likely destroy the module. Always double-check your connections.Battery capacity: Match the charging current to your battery’s capacity. While the module is set to 1A by default, you may need to reduce this for lower-capacity batteries to prevent overheating.Load sharing: Do not attempt to run a load and charge the battery simultaneously, as the module cannot accurately determine the charge termination and could overcharge the battery.
