How to Use TP4056: Examples, Pinouts, and Specs

The TP4056, manufactured by Makers (Part ID: TP4036), 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 TP4056 is widely used in portable electronics, power banks, and DIY battery-powered projects due to its simplicity, reliability, and built-in safety features.

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

The TP4056 is a versatile and compact IC with the following key specifications:

The TP4056 IC has 8 pins, each serving a specific function. Below is the pin configuration:

1. Power Supply: Connect a DC power source (e.g., USB 5V) to the VCC pin. Ensure the input voltage is within the range of 4.0V to 8.0V.
2. Battery Connection: Connect the positive terminal of the lithium-ion battery to the BAT pin and the negative terminal to GND.
3. Programming Charging Current: Use an external 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, using a 1.2kΩ resistor sets the charging current to 1A.
4. Status Indicators: Connect LEDs to the CHRG and STDBY pins for visual charging status. CHRG indicates charging in progress, while STDBY indicates charging completion.
5. Thermal Regulation: Ensure proper heat dissipation by placing the IC on a PCB with adequate thermal pads.

• Battery Safety: Always use the TP4056 with a single-cell lithium-ion battery. Do not connect multiple cells in series or parallel.
• Thermal Management: Avoid overheating by ensuring proper ventilation or using a heat sink if necessary.
• Input Voltage: Ensure the input voltage does not exceed 8.0V to prevent damage to the IC.
• NTC Thermistor: For enhanced safety, connect an NTC thermistor to the TEMP pin to monitor battery temperature during charging.

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 in progress)
#define STDBY_PIN 3 // Pin connected to STDBY (charging complete)

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. Problem: The battery is not charging.

   • Solution: Check the input voltage at the VCC pin. Ensure it is within the range of 4.0V to 8.0V. Verify the battery connection and ensure the polarity is correct.

2. Problem: The IC overheats during operation.

   • Solution: Reduce the charging current by increasing the value of the RPROG resistor. Ensure proper heat dissipation by using a PCB with thermal pads.

3. Problem: Status LEDs are not functioning.

   • Solution: Verify the connections to the CHRG and STDBY pins. Ensure the LEDs are connected with appropriate current-limiting resistors.

4. Problem: Charging current is too high or too low.

   • Solution: Recalculate and adjust the RPROG resistor value using the formula ( I_{CHG} = \frac{1200}{R_{PROG}} ).

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

   • No, the TP4056 is designed for single-cell lithium-ion batteries only. Charging multiple cells in series can lead to overcharging and damage.

2. What happens if the input voltage exceeds 8.0V?

   • The TP4056 may be damaged if the input voltage exceeds its maximum rating. Always ensure the input voltage is within the specified range.

3. Is it necessary to use an NTC thermistor?

   • While not mandatory, using an NTC thermistor connected to the TEMP pin enhances safety by monitoring the battery temperature during charging.

4. Can I adjust the charging voltage?

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

By following this documentation, users can safely and effectively integrate the TP4056 into their projects for reliable lithium-ion battery charging.