Intro: Using 2 Shift Registers(74HC595) to Drive 16 LEDs
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)
1 Arduino Uno
2 electrolytic capacitors ;10 Uf
2 long breadbaords
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 .