The 74HC595N is a simple 8-bit shift register IC. Simply put, this shift register is a device that allows additional inputs or outputs to be added to a microcontroller by converting data between parallel and serial formats. Your chosen microprocessor is able to communicate with The 74HC595N using serial information then gathers or outputs information in a parallel (multi-pin) format. Essentially it takes 8 bits from the serial input and then outputs them to 8 pins.
This small DIP packaged IC contains an 8-bit, serial-in-parallel-out shift register that feeds an 8-bit D-type storage register with parallel 3-state outputs.
Output Pins (Q1 to Q7)
The 74hc595 has 8 output pins out of which 7 are these pins. They can be controlled serially
Connected to the Ground of the circuit
(Q7) Serial Output
This pin is used to connect more than one 74hc595 as cascading
(MR) Master Reset
Resets all outputs as low. Must be held high for normal operation
This is the clock pin to which the clock signal has to be provided from MCU/MPU
The Latch pin is used to update the data to the output pins. It is active high
(OE) Output Enable
The Output Enable is used to turn off the outputs. Must be held low for normal operation
(DS) Serial Data
This is the pin to which data is sent, based on which the 8 outputs are controlled
The first output pin.
This pin powers the IC, typically +5V is used.
- 8-bit, Serial In – Parallel out Shift register
- Operating Voltage: 2V to 6V
- Power Consumption: 80uA
- Output source/sink current: 35mA
- Output Voltage is equal to Operating voltage
- Minimum high-level Input Voltage: 3.15V @(Vcc=4.5V)
- Maximum low-level Input Voltage: 1.35V @(Vcc=4.5V)
- Can be easily cascaded with more IC to get more outputs
- Maximum Clock Frequency: 25Mhz @4.5V
- Available in 16-pin PDIP, GDIP, PDSO packages
Where to Use 74HC595 IC:-
The 74HC595 is an 8-bit Serial In – Parallel Out Shift Register, i.e. it can receive (input) data serially and control 8 output pins in parallel. This comes in very handy where do not have enough GPIO pins on our MCU/MPU to control the required number of outputs. It is often used in projects where relatively a large number of LED's has to be controlled through the Microcontroller. It can also be used to interface LCD screen since they can acts as the data bit for the LCD displays. It can also be used to control 5V loads like relays through a 3.3V microcontroller since the high-level voltage is only 3.15. So if you are looking for an IC to save on your GPIO pins on the Microcontroller then this IC might be the right choice for you.
How to Use a 74HC595 IC:-
- 1 x 74HC595 IC