How to Use TP4056: Examples, Pinouts, and Specs

The TP4056 is a lithium-ion battery charger IC designed for single-cell lithium-ion or lithium-polymer batteries. It provides a constant current/constant voltage (CC/CV) charging profile, ensuring safe and efficient charging. The IC integrates several safety features, including thermal regulation, over-voltage protection, and automatic charge termination. Its compact design and ease of use make it a popular choice for portable electronics, DIY projects, and battery-powered devices.

• Charging single-cell lithium-ion or lithium-polymer batteries
• Power banks and portable chargers
• Wearable devices
• DIY electronics projects
• Battery management systems

The TP4056 is a versatile and reliable charging IC. Below are its key technical details:

The TP4056 is typically available in an 8-pin SOP package. Below is the pinout and description:

1. Power Supply: Connect a 5V DC power source (e.g., USB) to the VCC pin. Ensure the input voltage is within the 4.0V–8.0V range.
2. Battery Connection: Connect the positive terminal of the lithium-ion battery to the BAT pin and the negative terminal to GND.
3. Set Charging Current: Use a resistor (Rprog) between the PROG pin and GND to set the charging current. The charging current can be calculated using the formula: [ I_{CHG} = \frac{1000}{R_{PROG}} ] For example, a 1.2kΩ resistor sets the charging current to approximately 833mA.
4. Status Indicators: Connect LEDs to the CHRG and STDBY pins for visual charging status. Use a current-limiting resistor (e.g., 1kΩ) in series with each LED.
5. Thermal Protection: Optionally, connect an NTC thermistor to the TEMP pin for temperature monitoring. If unused, connect TEMP to GND.

• Battery Compatibility: Ensure the battery is a single-cell lithium-ion or lithium-polymer type with a nominal voltage of 3.7V.
• Heat Dissipation: The TP4056 may generate heat during operation. Use proper heat sinking or ensure adequate ventilation.
• Input Voltage: Avoid exceeding the maximum input voltage of 8.0V to prevent damage to the IC.
• Reverse Polarity: Ensure correct polarity when connecting the battery to avoid damage.

The TP4056 can be used in conjunction with an Arduino UNO to monitor battery voltage. Below is an example code snippet:

// Example: Monitor battery voltage using Arduino UNO
// Connect the BAT pin of TP4056 to an analog pin (e.g., A0) on Arduino

const int batteryPin = A0;  // Analog pin connected to TP4056 BAT pin
float voltageDividerRatio = 2.0; // Adjust if using a voltage divider
float referenceVoltage = 5.0;    // Arduino reference voltage (5V for UNO)

void setup() {
  Serial.begin(9600); // Initialize serial communication
}

void loop() {
  int rawValue = analogRead(batteryPin); // Read analog value from BAT pin
  float batteryVoltage = (rawValue / 1023.0) * referenceVoltage * voltageDividerRatio;

  // Print battery voltage to the Serial Monitor
  Serial.print("Battery Voltage: ");
  Serial.print(batteryVoltage);
  Serial.println(" V");

  delay(1000); // Wait for 1 second before next reading
}

Note: If the battery voltage exceeds the Arduino's analog input range, use a voltage divider to scale it down.

1. No Charging Current

   • Cause: Incorrect Rprog resistor value or damaged IC.
   • Solution: Verify the Rprog resistor value and ensure it is properly connected. Check the input voltage and replace the IC if necessary.

2. Overheating

   • Cause: High input voltage or insufficient heat dissipation.
   • Solution: Ensure the input voltage is within the 4.0V–8.0V range. Add a heatsink or improve ventilation.

3. LED Indicators Not Working

   • Cause: Incorrect LED connections or damaged LEDs.
   • Solution: Verify the LED polarity and current-limiting resistor values. Replace damaged LEDs.

4. Battery Not Charging

   • Cause: Faulty battery connection or incompatible battery type.
   • Solution: Check the battery connections and ensure the battery is a single-cell lithium-ion or lithium-polymer type.

• Can I use the TP4056 to charge multiple batteries in series?

  • No, the TP4056 is designed for single-cell batteries only. Charging multiple cells in series requires a dedicated battery management system.

• What happens if the input voltage exceeds 8.0V?

  • Exceeding 8.0V can damage the IC. Use a regulated power supply to prevent overvoltage.

• Can I adjust the charging voltage?

  • No, the charging voltage is fixed at 4.2V ± 1%. It cannot be adjusted.

• Is the TP4056 suitable for fast charging?

  • The TP4056 supports charging currents up to 1A, which is suitable for most single-cell batteries. For higher currents, consider alternative ICs.

By following this documentation, you can safely and effectively use the TP4056 in your projects.