LED Heart PWM Fading

Project Info
Author: Chris
Difficulty: Medium
Time Invested: 7 Hours

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           With my Grandma's birthday fast approaching I wanted to put something together that was not too complicated but still sweet enough to make for a cool widget gift. Since fading LEDs never seem to go out of style and grandmas always love to see a heart, putting two and two together here was a no-brainer.
           The concept for this small birthday present was to create a small heart shape with red LEDs and then to draw a heart shape underneath it on the PCB as a backdrop. Then a microcontroller was added to control the LEDs for both fade and pattern control. Controlling LEDs via PWM allows us to save precious battery life and control the exact brightness of each specific LED.

LED Heart PWM Fading - Demonstration

LED Heart PWM Fading - Project Setup

Purpose & Overview Of This Project
           The goal of this project is to create a PCB with some LEDs connected to a microcontroller. The LEDs should be individually controlled by the microcontroller so much so that each LED can be set to a different brightness level individually. With this control in place 6 modes of operation should be programmed:
  • LEDs 'around the heart'
  • A total heart fade-in-out
  • A wave-like fade bottom to top
  • A wave-like fade right to left
  • A single row fade in and out
  • A single column fade in and out.
To achieve this goal, we will use 16 5mm Red LEDs for the heart and a PIC 18F252 microcontroller for the processing. Some other components will be needed as well, so please continue on to see the parts list.