How to Use 3in1DC: Examples, Pinouts, and Specs

The 3in1DC module, manufactured by DigiKey (Part ID: 123some), is a versatile 3-in-1 DC module that integrates a DC-DC converter, a voltage regulator, and a power management system. This compact and efficient component is designed to simplify power management in electronic circuits, making it ideal for a wide range of applications.

• Embedded Systems: Provides stable power for microcontrollers and sensors.
• IoT Devices: Ensures efficient power conversion for battery-powered devices.
• Robotics: Supplies regulated power to motors and control systems.
• Prototyping: Simplifies power management in breadboard and PCB designs.
• Portable Electronics: Extends battery life by optimizing power usage.

The following table outlines the key technical details of the 3in1DC module:

The 3in1DC module has a simple pinout for easy integration into circuits:

1. Connect Input Voltage:
   • Connect the VIN pin to a DC power source within the range of 4.5V to 24V.
   • Connect the GND pin to the ground of your circuit.
2. Select Output Voltage:
   • Use the SEL1 and SEL2 pins to configure the desired output voltage:
     • SEL1 = 0, SEL2 = 0 → 1.8V
     • SEL1 = 1, SEL2 = 0 → 3.3V
     • SEL1 = 0, SEL2 = 1 → 5V
   • Leave SEL1 and SEL2 unconnected if the default output voltage (3.3V) is sufficient.
3. Enable the Module:
   • Connect the EN pin to VIN to enable the module.
   • Leave the EN pin unconnected or pull it to GND to disable the module.
4. Connect the Load:
   • Connect your load to the VOUT pin and GND.

• Input Voltage: Ensure the input voltage is within the specified range to avoid damage.
• Heat Dissipation: If operating at high currents, consider adding a heatsink or improving airflow.
• Capacitors: Add decoupling capacitors (e.g., 10µF and 0.1µF) near the VIN and VOUT pins for improved stability.
• Voltage Selection: Avoid changing SEL1 and SEL2 configurations while the module is powered.

The following example demonstrates how to power an Arduino UNO using the 3in1DC module:

• Connect the VIN pin of the 3in1DC to a 12V DC power source.
• Set SEL1 = 0 and SEL2 = 1 to configure the output voltage to 5V.
• Connect the VOUT pin of the 3in1DC to the 5V pin of the Arduino UNO.
• Connect the GND pin of the 3in1DC to the GND pin of the Arduino UNO.

// Example code to blink an LED connected to pin 13 of the Arduino UNO
// Ensure the 3in1DC module is providing a stable 5V to the Arduino UNO

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

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:

   • Ensure the EN pin is connected to VIN to enable the module.
   • Verify that the input voltage is within the specified range (4.5V to 24V).
   • Check for loose or incorrect connections.

2. Overheating:

   • Ensure the load does not exceed the maximum output current (2A).
   • Improve heat dissipation by adding a heatsink or increasing airflow.

3. Unstable Output Voltage:

   • Add decoupling capacitors (e.g., 10µF and 0.1µF) near the VIN and VOUT pins.
   • Verify that the input power source is stable and not fluctuating.

4. Incorrect Output Voltage:

   • Double-check the SEL1 and SEL2 pin configurations.
   • Ensure the pins are not left floating if a specific voltage is required.

Q: Can the 3in1DC module be used with a battery?
A: Yes, the module can be powered by a battery as long as the input voltage is within the range of 4.5V to 24V.

Q: What happens if the input voltage exceeds 24V?
A: The module may be damaged. Always ensure the input voltage stays within the specified range.

Q: Can I use the 3in1DC to power multiple devices?
A: Yes, as long as the total current draw does not exceed 2A.

Q: Is the module protected against reverse polarity?
A: No, the module does not have reverse polarity protection. Ensure correct polarity when connecting the input voltage.