How to Use MH-MINI-360 VoltReg: Examples, Pinouts, and Specs

The MH-MINI-360 VoltReg is a compact, efficient, and reliable step-down voltage regulator designed to provide a stable output voltage. It is widely used in low-power applications to ensure consistent performance, even when the input voltage fluctuates. Its small size and high efficiency make it ideal for portable devices, battery-powered systems, and embedded electronics.

• Powering microcontrollers (e.g., Arduino, ESP32, Raspberry Pi Pico)
• Battery-powered devices
• LED drivers
• Robotics and IoT projects
• General-purpose voltage regulation in low-power circuits

The MH-MINI-360 VoltReg is a buck converter that steps down a higher input voltage to a lower, stable output voltage. Below are its key technical details:

The MH-MINI-360 has four pins for easy integration into circuits. Below is the pinout:

1. Connect the Input Voltage (VIN):

   • Supply a DC voltage between 4.75V and 23V to the VIN pin.
   • Ensure the input voltage is higher than the desired output voltage.

2. Connect the Ground (GND):

   • Connect the GND pin to the ground of your circuit.

3. Set the Output Voltage (VOUT):

   • Use the onboard potentiometer to adjust the output voltage.
   • Turn the potentiometer clockwise to increase the output voltage and counterclockwise to decrease it.
   • Use a multimeter to measure the output voltage while adjusting.

4. Connect the Load:

   • Attach the load to the VOUT pin and GND pin.
   • Ensure the load does not exceed the maximum current rating of 3A.

• Heat Dissipation: If the load current exceeds 1.5A, consider adding a heatsink to prevent overheating.
• Input Voltage Margin: Ensure the input voltage is at least 1.5V higher than the desired output voltage for proper regulation.
• Capacitors: Add input and output capacitors (e.g., 10 µF) close to the regulator to improve stability and reduce noise.
• Polarity Protection: Use a diode at the input to protect the regulator from reverse polarity connections.

The MH-MINI-360 can be used to power an Arduino UNO by stepping down a 12V input to 5V. Below is an example circuit and code:

• Connect a 12V DC power source to the VIN pin.
• Connect the GND pin to the ground of the power source and Arduino.
• Adjust the potentiometer to set the output voltage to 5V.
• Connect the VOUT pin to the Arduino's 5V pin.

// Example code to blink an LED using Arduino UNO powered by MH-MINI-360
// Ensure the MH-MINI-360 is set to output 5V before connecting to Arduino.

const int ledPin = 13; // Built-in LED pin on Arduino UNO

void setup() {
  pinMode(ledPin, OUTPUT); // Set LED pin as output
}

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

1. Output Voltage Not Stable:

   • Check the input voltage to ensure it is within the specified range.
   • Add input and output capacitors to improve stability.

2. Regulator Overheating:

   • Ensure the load current does not exceed 3A.
   • Add a heatsink or improve ventilation around the regulator.

3. No Output Voltage:

   • Verify all connections, especially VIN and GND.
   • Check the potentiometer setting and adjust as needed.
   • Ensure the input voltage is at least 1.5V higher than the desired output voltage.

4. Load Not Powering On:

   • Measure the output voltage with a multimeter to confirm proper regulation.
   • Ensure the load's power requirements are within the regulator's capacity.

Q: Can the MH-MINI-360 be used with AC input?
A: No, the MH-MINI-360 requires a DC input voltage. Use a rectifier and filter circuit to convert AC to DC before connecting.

Q: How do I adjust the output voltage precisely?
A: Use a multimeter to measure the output voltage while turning the potentiometer slowly. Fine-tune until the desired voltage is achieved.

Q: Is the MH-MINI-360 suitable for powering sensitive devices?
A: Yes, but add input and output capacitors to reduce noise and improve stability for sensitive devices.

Q: Can I use the MH-MINI-360 to charge batteries?
A: It is not recommended for direct battery charging unless additional circuitry is used to manage charging profiles.

By following this documentation, you can effectively integrate the MH-MINI-360 VoltReg into your projects and ensure reliable performance.