LED Heart Box




Introduction: LED Heart Box

About: I do engineering design for machines and electronics but do love science, art and history.

This is a simple LED accessory for you to decorate your Valentine's day.

Step 1: Preparation

You need the following materials.

  1. Red LED diode (dia. 3mm) , 2 pcs
  2. 50 Ohms resistor, 1 pcs
  3. HDX contactless sensor, 1 pcs
  4. CR2032 coin battery, 1 pcs
  5. CR2032 coin battery holder, 1 pcs
  6. 3d printed Heart-Box component, 2 pcs (in the attachments)
  7. 30 AWG solid wire
  8. Lead-free solder wire
  9. Hot glue
  10. Masking Tape (Optional)
  11. Small fasteners, 3 pcs (Optional)

You may need the following tools.

  1. Soldering iron
  2. 30 AWG wrapping tool
  3. Hot glue gun

Step 2: Circuit Diagram

The LEDs are powered by the 3V coin battery. I added a contactless HDX sensor to control the ON/OFF of the circuit. The 50 Ohms is added to limit the current.

Step 3: Solder the LEDs

To connect the LEDs, I did not use any extra wire. I bent the leads of LED to form the circuit's track. Firstly, I soldered the cathode's leads. Then, I soldered the leads.

Step 4: Solder the Resistor

The leads of resistor were shortened. Firstly, I soldered the resistor to the negative lead of the battery holder. Then, I soldered the other lead of resistor to the anode of LEDs. In addition, I put a masking tape to protect the battery case.

Step 5: Connect the HDX Contactless Sensor

Firstly, I wrapped 30 AWG wires to the sensor's leads. Then, the connection is secured by soldering. Next, the wires were connected to the LEDs and the battery holder.

Step 6: Test the Circuit

The LEDs will be switched on when the sensor is turned upward.

Step 7: Combine the Components and Adjust the Position of LEDs

I used hot glue to cover the solder joints and secure the position of each components. In addition, I adjusted the orientation and the location of the LEDs.

Step 8: Optional

You can install reflective tape to enhance the visual effect of the LEDs. Furthermore, you can close the lid by hot glue or screws.

Step 9: Final Test

Hope you enjoy it! Happy Valentine's Day!

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    Reply 5 years ago

    Thank you~


    5 years ago

    great project! I did something similar a few years ago but made the case out of sheets of plastic I dremeled out and a added a 555 timer to the circuit to make the heart blink(beat).


    Reply 5 years ago

    Yes, I would like to add this feature too. It would be more interesting if the LEDs blink~ I want to make it small but this item has already been larger than I expected. Space is not enough for me to add the 555 timer unless I made the PCB.