App-Notes » Power Electronics » TP4056 Lithium Battery Charger IC: Features and Applications

TP4056 Lithium Battery Charger IC: Features and Applications

battery charger lithium ion tp4056 power electronics circuit design

The TP4056 is a widely used lithium-ion (Li-ion) battery charger IC, offering a straightforward and efficient way to charge single-cell lithium-ion batteries. Its ease of use and integrated safety features make it a popular choice for portable electronics and DIY projects.

Features of the TP4056

  • Constant Current / Constant Voltage (CC/CV) Charging: The TP4056 uses a two-step charging algorithm, ensuring efficient battery charging while preventing overcharging.

  • Input Voltage Range: It supports a wide input voltage range of 4.5V to 5.5V, making it compatible with various power sources, including USB chargers.

  • Programmable Charge Current: The charge current can be adjusted using an external resistor, providing flexibility to match specific battery requirements.

  • Integrated Thermal Regulation: This feature prevents overheating during charging by reducing the charge current if the IC’s internal temperature exceeds a set limit.

  • Low Quiescent Current: The TP4056 consumes very little current in sleep mode, extending battery life in low-power applications.

  • Battery Status Indication: A dedicated LED output (CHRG) indicates the charging status, keeping users informed.

  • Short Circuit Protection: Built-in protection prevents damage to both the IC and the battery in the event of a short circuit.

  • Compact Size: Available in a small SOT-23 package, making it suitable for applications where space is limited.

TP4056 Pinout Diagram

The TP4056 typically comes in an 8-pin package. The pin configuration is detailed below.

TP4056 Lithium Battery Charger IC

Figure 1: TP4056 Lithium Battery Charger IC Pin Diagram

Pin NumberNameDescription
1TEMPBattery temperature detection input. If the TEMP pin voltage is less than 45% or greater than 80% of the input voltage, it indicates the battery temperature is too low or too high, and charging is suspended.
2PROGCharge Current Program, Charge Current Monitor, and Shutdown Pin.
3GNDGround.
4VCCPositive Input Supply Voltage. Supplies power to the charger. VCC can range from 4.25V to 6.5V and should be bypassed with at least a 10uF capacitor.
5BATCharge Current Output. Provides charge current to the battery and regulates the final float voltage to 4.2V.
6STDBY’The completion of battery charging instructions side. When the battery charge is complete, STDBY pulled low by internal switches, indicating the completion of charging. In addition, STDBY pin will be in a high-impedance state.
7CHRG’Open-Drain Charge Status Output. When the battery is charging, the CHRG pin is pulled low by an internal N-channel MOSFET. When the charge cycle is completed, CHRG pin will be in a high-impedance state.
8CEChip enable input. A high input level allows normal operation; a low input level disables charging, putting the TP4056 into a prohibited charging status.

Working Principle

The TP4056 operates in two main phases:

  1. Constant Current Phase (CC): Initially, the IC supplies a constant current to the battery until its voltage reaches approximately 4.2V (the full charge voltage for Li-ion batteries).

  2. Constant Voltage Phase (CV): Once the battery voltage reaches 4.2V, the charger switches to constant voltage mode, gradually reducing the charging current until it approaches zero.

TP4056 Lithium Battery Charger circuit

Figure 2: TP4056 Lithium Battery Charger Circuit

Benefits

  • Simplicity: The TP4056 requires very few external components, making it easy to design into circuits and implement.

  • Safety: Built-in safety features protect against overcharging, overheating, and short circuits, improving user safety.

  • Versatility: It can be used in a variety of applications, from DIY projects to commercial electronic devices.

Applications

  • Power Banks: Used in portable power bank circuits for efficient battery charging.

  • Wireless Devices: Ideal for charging batteries in wireless sensors and devices.

  • IoT Projects: Commonly used in Internet of Things (IoT) devices that require rechargeable batteries.

Conclusion

The TP4056 battery charger IC is a versatile and efficient solution for charging single-cell lithium-ion batteries, making it a popular choice for both hobbyists and professional engineers. Its robust features and ease of integration allow for safe and reliable battery management in a wide range of applications.