How to Use Adafruit USB DC Solar LiPo Charger: Examples, Pinouts, and Specs

The Adafruit USB DC Solar LiPo Charger is a versatile and portable charging module designed for lithium polymer (LiPo) batteries. It allows for charging via solar panels or a USB power source, making it an ideal component for eco-friendly projects, portable electronics, and outdoor applications where conventional power sources are unavailable.

• Solar-powered projects
• Portable battery chargers
• Remote sensing equipment
• DIY power banks
• Outdoor electronics

• Input Voltage (Solar/USB): 6V (minimum)
• Charge Current: 500mA (default), adjustable up to 1A
• Battery Voltage: 3.7V LiPo batteries
• Maximum Output Load: 1A
• Indicator LEDs:
  • CHRG: Charging status
  • DONE: Charge complete

1. Connecting the Battery:

   • Connect the positive terminal of the LiPo battery to the BAT pin.
   • Connect the negative terminal of the LiPo battery to the GND pin.

2. Powering the Charger:

   • To charge via solar power, connect a 6V solar panel to the CNCT pin.
   • To charge via USB, connect a USB power source to the USB pin.

3. Connecting the Load:

   • Connect the load circuit to the LOAD pin and GND.

• Ensure the LiPo battery voltage and capacity are compatible with the charger.
• Do not exceed the recommended solar panel voltage.
• Adjust the charge current according to the battery's specifications.
• Avoid placing the solar panel under direct sunlight without a battery connected.
• Monitor the charging process to prevent overcharging.

• LEDs not lighting up:

  • Check connections to the battery and power source.
  • Ensure the solar panel is receiving sufficient light or the USB source is active.

• Battery not charging:

  • Verify the battery's health and connections.
  • Ensure the charge current is set correctly for the battery.

• Overheating:

  • Reduce the charge current if the charger or battery becomes too hot.
  • Provide adequate ventilation.

Q: Can I charge multiple batteries at once? A: No, the charger is designed for a single LiPo battery.

Q: What size solar panel should I use? A: A 6V solar panel with sufficient wattage to provide the desired charge current (up to 1A).

Q: How do I know when the battery is fully charged? A: The DONE LED will light up when the battery is fully charged.

Q: Can I use this charger with other types of batteries? A: This charger is specifically designed for 3.7V LiPo batteries and may not be suitable for other types.

Q: Is it safe to leave the charger unattended? A: While the charger has built-in protection, it's always best to monitor the charging process, especially when adjusting the charge current.

// This example assumes you are using the Adafruit USB DC Solar LiPo Charger
// to charge a battery and power an Arduino UNO indirectly via the battery.

void setup() {
  pinMode(LED_BUILTIN, OUTPUT); // Set the built-in LED as an output
}

void loop() {
  digitalWrite(LED_BUILTIN, HIGH); // Turn on the LED
  delay(1000);                     // Wait for a second
  digitalWrite(LED_BUILTIN, LOW);  // Turn off the LED
  delay(1000);                     // Wait for a second
}

// Note: This code does not interact directly with the charger.
// It's a simple blink example to demonstrate a load on the battery.

Remember, the Adafruit USB DC Solar LiPo Charger does not require any code to operate as it is a standalone charging module. The example provided is to illustrate how a charged battery might power an Arduino UNO, which in turn runs a simple blink program.