INTRODUCTION:

Today here I am going to make a pretty Arduino project using RGB LEDs. Here I am using Common cathode type RGB LEDs and controlling these LEDs with 74HC595(Serial input Parallel output) ShiftRegister and Arduino nano microcontroller development board. So let's get started

LIST OF COMPONENTS AND MODULES:

• Arduino nano (1)

• 74HC595 ShiftRegister (4)

• RGB LEDs (Common Cathode type) (10)

• Bread Board (3)

• Jumper wires

• 100 Ohm Resistors (30)

• Mini B USB Cable (1)

RGB LED

RGB LED is a special type of LED that can emits basically any color of visible light. By mixing three primary colors (Red, Green and Blue). RGB LED Basically a combination of these three color LEDs connected either in common anode or common cathode configuration as shown in the given Fig-1.

Actual view of RGB LED

here I am using Common cathode type RGB LEDs and I am also using 100 ohm resistor to limit the value of flowing current.

74HC595 ShiftRegister:

74HC595 is a 8 bit Serial input Parallel output (SIPO) shift register with three output states. 74HC595 shift register also contains a 8 bit latch to hold the binary data. The pin diagram of 74HC595 Shift register has given below.

PIN DIAGRAM OF 74HC595

PICTURES OF MY WORK:

EXPANDED TECHNICAL DETAILS

Pin Resource Optimization

This project demonstrates how to control multiple RGB LEDs using only 3 data pins from the Arduino.

• 74HC595 Shift Register: This IC acts as a Serial-to-Parallel converter. The Arduino sends a 24-bit stream (8 bits for Red, 8 for Green, 8 for Blue) which the shift register "latches" into permanent outputs.
• Scaling Potential: Multiple 74HC595s can be daisy-chained together, allowing you to control dozens of RGB LEDs without using up all the Arduino's GPIO pins.

Logic Animation

• ShiftOut Operation: The firmware uses the shiftOut() command. This allows for the creation of complex color-shifting patterns and scrolling animations that would normally be impossible on a low-pin-count microcontroller.