How to Use TP4056: Examples, Pinouts, and Specs

The TP4056 is a lithium-ion battery charger IC designed for single-cell lithium-ion 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 and IoT gadgets
• DIY electronics projects
• Battery management systems

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

The TP4056 IC has 8 pins, each serving a specific function. Below is the pinout and description:

1. Power Supply: Connect a regulated DC power supply (4.0V to 8.0V) to the VCC pin. Ensure the supply can provide sufficient current for charging.
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{1200}{R_{PROG}} ] For example, a 1.2kΩ resistor sets the charging current to 1A.
4. Status Monitoring: Use the CHRG and STDBY pins to monitor the charging status. These pins are open-drain and require pull-up resistors.
5. Temperature Monitoring: Connect an NTC thermistor to the TEMP pin for battery temperature monitoring. If unused, connect the TEMP pin to GND.

• Thermal Management: Ensure proper heat dissipation, especially when charging at high currents. Use a heat sink or place the IC on a PCB with good thermal conductivity.
• Input Voltage: Avoid exceeding the maximum input voltage of 8.0V to prevent damage to the IC.
• Battery Protection: Use a protection circuit module (PCM) with the battery to prevent over-discharge and over-current conditions.

The TP4056 can be used with an Arduino UNO to monitor the charging status. Below is an example code:

// TP4056 Charging Status Monitoring with Arduino UNO
// Connect CHRG pin to Arduino pin 2 and STDBY pin to Arduino pin 3

#define CHRG_PIN 2  // Pin connected to CHRG (charging status)
#define STDBY_PIN 3 // Pin connected to STDBY (standby status)

void setup() {
  pinMode(CHRG_PIN, INPUT);  // Set CHRG pin as input
  pinMode(STDBY_PIN, INPUT); // Set STDBY pin as input
  Serial.begin(9600);        // Initialize serial communication
}

void loop() {
  int chrgStatus = digitalRead(CHRG_PIN);   // Read CHRG pin status
  int stdbyStatus = digitalRead(STDBY_PIN); // Read STDBY pin status

  if (chrgStatus == LOW) {
    Serial.println("Battery is charging...");
  } else if (stdbyStatus == LOW) {
    Serial.println("Charging complete.");
  } else {
    Serial.println("No battery connected or idle state.");
  }

  delay(1000); // Wait for 1 second before checking again
}

1. IC Overheating

   • Cause: High charging current or insufficient heat dissipation.
   • Solution: Reduce the charging current by increasing the Rprog resistor value. Ensure proper PCB design for heat dissipation.

2. Battery Not Charging

   • Cause: Incorrect wiring or insufficient input voltage.
   • Solution: Verify all connections and ensure the input voltage is within the 4.0V to 8.0V range.

3. CHRG and STDBY Pins Not Responding

   • Cause: Missing pull-up resistors on the status pins.
   • Solution: Add pull-up resistors (e.g., 10kΩ) to the CHRG and STDBY pins.

4. Charging Current Too Low

   • Cause: Incorrect Rprog resistor value.
   • Solution: Recalculate and replace the Rprog resistor to achieve the desired charging current.

Q: Can the TP4056 charge multiple batteries in series?
A: No, the TP4056 is designed for single-cell lithium-ion batteries only. Charging multiple cells in series requires a specialized multi-cell charger.

Q: What happens if the input voltage exceeds 8.0V?
A: Exceeding 8.0V can damage the IC. Always use a regulated power supply within the specified range.

Q: Can I use the TP4056 without the TEMP pin?
A: Yes, if temperature monitoring is not required, connect the TEMP pin directly to GND.

Q: How do I adjust the charging voltage?
A: The charging voltage is fixed at 4.2V and cannot be adjusted. For other voltages, consider using a different IC.

This concludes the TP4056 documentation.