Introduction: Using 2 Shift Registers(74HC595) to Drive 16 LEDs

About: I have an Associate degree in Electronics Technology from Joliet Junior College . I have worked as an electronic technician in telecommunications and at Commonwealth Edison .Presently ,I enjoy electronics as …

This circuit will use 2 shift registers(74HC595) .The shift registers will drive as outputs 16 LEDs. Each shift register will drive 8 LEDs .The shift registers are wired so that each shift register outputs will look like a duplicate of the other.

Step 1: What Is a Shift Register?

Shift registers are sequential logic circuits.They are capable of storage and transfer of data.

Shift registers consist of many flip flops and clocks which are connected together .The outputs of the shift the shift registers are shifted or changed according to the clocks (pulsed outputs).

Step 2: Uses of Shift Registers

Shift registers are digital memory circuits used in calculators and computers .Shift registers can be used to expand the number of outputs from a microcontroller like Arduino.

Step 3: Electronic Components Used in the Circuit.

2 74HC595 shift registers

16 ;1 k resistors(brown,black,red)

16 LEDs

1 Arduino Uno

2 electrolytic capacitors ;10 Uf

2 long breadbaords

wires .

Step 4: Setting Up the Circuit

The outputs are Qa to Qh .Wire Qa first and then go to each other output as shown is the diagram.

pin14 is SER is connected to Arduino digital pin 11 .the SER is the DATA input which will be shift in.

Pin12 is RCLK (LATCH) is connected to

Arduino digital pin 8

Pin11 is SRCLK(CLOCK) is connected to Arduino digital pin 12

every time this pin goes high(1) the values in the shift register will shift by 1 bit .

Vcc is pin 16 is connected to the red breadboard rail

pin 8 is connected to ground

Arduino 5 volts is connected to the red rail of the breadboard

Arduino grounsd is connected to the black rail

Connect grounds of the boards together as shown is the diagram.

Step 5: How the Circuit Works

The 3 different inputs(CLOCK,LATCH,DATA) will change the voltages of the outputs as seen on the LEDs.The CODE will program the sequence of the LEDs and the speed of the LEDs turning on and off.

Step 6: The Outputs Will Shift First Left to Right Quickly

The LEDS will move left to right quickly.

Step 7: Then the LEDS Wil Go From Right to Left Very Quickly

The LEDS change direction (right to left).

Step 8: Conclusion

I hope this project helps to understand shift registers and its uses. I enjoyed the project .It was tested on

Tinkercad and works .

There is a link, but you may need a Tinkercad account to see it .The link is posted above also with the CODE .

Thank you

Step 9: Video of Shift Registers

video of shift registers