The HLK-PM12 is a compact, highly efficient AC-DC power supply module designed to convert alternating current (AC) from the mains to a stable 12 Volt direct current (DC). This module is widely used in low power applications such as smart home devices, control systems, and IoT projects due to its small form factor and ease of integration into existing circuits.
This circuit is designed to monitor and control a 120V AC outlet using an ESP32 microcontroller. It includes a PZEM004t module for measuring voltage, current, and power, and a 12V relay to switch the outlet on and off. An OLED display is used to show real-time data, and the HLK-PM12 module provides the necessary 5V and 3.3V power to the components.
Open Project in Cirkit Designer
This circuit is a control system using an ESP32 microcontroller to manage a 4-channel relay module, which in turn controls various loads. The relays are activated by rocker switches and provide visual feedback through LEDs, while power is supplied and regulated by an HLK-PM12 module and protected by a fuse and circuit breaker.
Open Project in Cirkit Designer
This is a smart control system featuring an ESP32C3 Supermini microcontroller for interfacing with various sensors and actuators. It includes temperature and humidity sensing, RGB LED strip control, user input via a pushbutton and rotary encoder, and AC power control through a two-channel relay. The system is powered by an AC source converted to DC by the HLK-PM12 module.
Open Project in Cirkit Designer
This circuit features a LilyGo-SIM7000G module for cellular communication and GPS functionality, interfaced with an RTC DS3231 for real-time clock capabilities. It includes voltage sensing through two voltage sensor modules, and uses an 8-channel opto-coupler for isolating different parts of the circuit. Power management is handled by a buck converter connected to a DC power source and batteries, with a fuse for protection and a rocker switch for on/off control. Additionally, there's an LED for indication purposes.
Open Project in Cirkit DesignerThe HLK-PM12 module boasts the following technical specifications:
| Parameter | Specification |
|---|---|
| Input Voltage | 100 - 240V AC |
| Output Voltage | 12V DC |
| Output Current | Up to 3A |
| Power Rating | 36W |
| Efficiency | >87% |
| Operating Temp. | -20°C to +60°C |
| Humidity | 5% to 95% Non-condensing |
| Isolation Voltage | 3000V AC |
| Dimensions | 34 x 20 x 15mm |
| Pin Number | Name | Description |
|---|---|---|
| 1 | L | AC Live Input |
| 2 | N | AC Neutral Input |
| 3 | -V | DC Output Negative (Ground) |
| 4 | +V | DC Output Positive |
AC Input Connection: Connect the AC live wire to pin 1 (L) and the neutral wire to pin 2 (N). Ensure that the connections are secure and insulated to prevent electrical hazards.
DC Output Connection: Connect the positive lead of your device or circuit to pin 4 (+V) and the negative lead to pin 3 (-V).
Mounting: Secure the HLK-PM12 module onto a PCB or within an enclosure, ensuring adequate ventilation for heat dissipation.
Q: Can I use the HLK-PM12 outdoors? A: The HLK-PM12 is not waterproof and should be housed in a suitable enclosure if used outdoors.
Q: Is it necessary to use a fuse with the HLK-PM12? A: Yes, it is recommended to use a fuse on the AC input for safety purposes.
Q: Can I adjust the output voltage of the HLK-PM12? A: No, the output voltage is fixed at 12V DC.
// No specific code is required for the HLK-PM12 as it is a power supply module.
// However, below is an example of how to power an Arduino UNO using the HLK-PM12.
// Connect the HLK-PM12 module to the Arduino UNO as follows:
// HLK-PM12 +V pin to Arduino UNO Vin pin
// HLK-PM12 -V pin to Arduino UNO GND pin
void setup() {
// Initialize digital pin LED_BUILTIN as an output.
pinMode(LED_BUILTIN, OUTPUT);
}
void loop() {
// Turn the LED on (HIGH is the voltage level)
digitalWrite(LED_BUILTIN, HIGH);
// Wait for a second
delay(1000);
// Turn the LED off by making the voltage LOW
digitalWrite(LED_BUILTIN, LOW);
// Wait for a second
delay(1000);
}
Note: When using the HLK-PM12 to power an Arduino UNO, ensure that the input voltage does not exceed the recommended Vin range for the Arduino UNO (6-20V). The HLK-PM12's 12V output is within this range and is suitable for powering the board.