How to Use HLK-PM12: Examples, Pinouts, and Specs

The HLK-PM12 is a compact and efficient AC-DC power module manufactured by Shenzhen Hi-Link Electronic Co., Ltd. It is designed to convert a wide range of AC input voltages (85-265V AC) into a stable 12V DC output. This module is widely used in applications requiring a reliable and space-saving power supply solution, such as IoT devices, home automation systems, industrial control circuits, and embedded systems.

• Powering microcontrollers and sensors in IoT projects
• Home automation devices
• Industrial control systems
• LED lighting systems
• Small appliances and consumer electronics

The HLK-PM12 is designed to provide a stable and efficient power supply with the following key specifications:

The HLK-PM12 module has six pins, as described in the table below:

1. Input Connection: Connect the AC(L) and AC(N) pins to the live and neutral wires of the AC mains supply, respectively. Ensure proper insulation and safety precautions when handling high-voltage AC connections.
2. Output Connection: Connect the +VOUT and -VOUT pins to the load or circuit requiring a 12V DC power supply. Ensure the load does not exceed the maximum output current of 250mA.
3. Mounting: Secure the module on a PCB or enclosure using appropriate mounting techniques. Ensure adequate spacing and insulation to prevent short circuits or accidental contact with high-voltage pins.
4. Filtering: For improved performance and reduced noise, consider adding external capacitors (e.g., 10µF electrolytic and 0.1µF ceramic) across the output terminals.

• Safety: Always handle the module with care, as it involves high-voltage AC input. Ensure proper insulation and avoid touching the module while it is powered.
• Load Requirements: Do not exceed the maximum output current of 250mA to prevent overheating or damage to the module.
• Ventilation: Ensure adequate ventilation around the module to prevent overheating, especially in high-temperature environments.
• Testing: Before connecting the module to your final circuit, test it with a dummy load to verify proper operation.

The HLK-PM12 can be used to power an Arduino UNO by providing a stable 12V DC supply. Below is an example circuit and code to blink an LED using the Arduino UNO powered by the HLK-PM12.

1. Connect the AC(L) and AC(N) pins of the HLK-PM12 to the AC mains supply.
2. Connect the +VOUT pin of the HLK-PM12 to the VIN pin of the Arduino UNO.
3. Connect the -VOUT pin of the HLK-PM12 to the GND pin of the Arduino UNO.
4. Connect an LED and a 220-ohm resistor to pin 13 of the Arduino UNO.

// Blink an LED connected to pin 13 of the Arduino UNO
// Ensure the HLK-PM12 is providing a stable 12V DC to the Arduino's VIN pin

void setup() {
  pinMode(13, OUTPUT); // Set pin 13 as an output pin
}

void loop() {
  digitalWrite(13, HIGH); // Turn the LED on
  delay(1000);            // Wait for 1 second
  digitalWrite(13, LOW);  // Turn the LED off
  delay(1000);            // Wait for 1 second
}

1. No Output Voltage

   • Cause: Incorrect AC input connection or insufficient input voltage.
   • Solution: Verify that the AC(L) and AC(N) pins are connected to the live and neutral wires of the AC mains supply. Ensure the input voltage is within the specified range (85-265V AC).

2. Overheating

   • Cause: Exceeding the maximum output current or poor ventilation.
   • Solution: Ensure the load does not exceed 250mA. Provide adequate ventilation around the module.

3. Noise or Ripple in Output

   • Cause: Insufficient filtering or high-frequency noise.
   • Solution: Add external capacitors (e.g., 10µF electrolytic and 0.1µF ceramic) across the output terminals to reduce noise.

4. Module Not Working After Power Surge

   • Cause: Damage due to a power surge or overvoltage.
   • Solution: Use a surge protector or fuse on the AC input to protect the module from power surges.

Q: Can the HLK-PM12 power a Raspberry Pi?
A: No, the HLK-PM12 cannot power a Raspberry Pi directly, as the Raspberry Pi typically requires higher current (e.g., 2.5A for Raspberry Pi 4) than the HLK-PM12 can provide (250mA maximum).

Q: Is the HLK-PM12 suitable for outdoor use?
A: The HLK-PM12 is not designed for outdoor use unless it is enclosed in a weatherproof and insulated housing.

Q: Can I use the HLK-PM12 with a 24V DC input?
A: No, the HLK-PM12 is designed for AC input only (85-265V AC). It cannot operate with a DC input.

Q: Does the HLK-PM12 require a heatsink?
A: No, the HLK-PM12 does not require a heatsink under normal operating conditions, as long as the load does not exceed 250mA and there is adequate ventilation.