74595 IC 8-bit Serial-In, Parallel-Out
The 74HC595 is a high-speed 8-bit serial-in, serial or parallel-out shift register with a storage register and 3-state outputs. Designed using advanced CMOS technology, it offers high noise immunity and low power consumption. This IC is particularly useful in microcontroller-based systems where GPIO pins are limited but multiple output devices need to be controlled. It receives data serially and outputs it in parallel, allowing you to drive multiple LEDs, 7-segment displays, or relays while conserving the microcontroller’s I/O resources.
A key feature of the 74HC595 is its ability to cascade multiple ICs together, enabling you to expand outputs indefinitely by daisy-chaining additional chips. The shift register is updated on the rising edge of the clock input, and the outputs can be latched using a separate latch pin. It operates at a wide voltage range, typically from 2V to 6V, and can deliver adequate current for driving low-power devices directly..
Key Features
8-bit serial-in, parallel-out shift register
Tri-state output capability
Cascadable for output expansion
Low power CMOS design
Wide operating voltage range (2V–6V)
High-speed data transfer (up to 100 MHz)
Compatible with TTL logic
Low static power consumption
Product Specifications Table
| Specification | Value |
|---|---|
| IC Name | 74HC595 |
| Type | 8-bit Shift Register |
| Package | DIP-16 / SOIC-16 |
| Operating Voltage | 2V to 6V |
| Max Clock Frequency | 100 MHz |
| Output Current | ±6 mA ‘ |
| Temperature Range | -40°C to +125°C |
| Number of Outputs | 8 (Q0–Q7) |
| Number of Control Pins | 3 (SER, SRCLK, RCLK) |
| Output Type | Tri-state |
Pin Configuration
| Pin Number | Symbol | Function |
|---|---|---|
| 1 | Q1 | Output 1 |
| 2 | Q2 | Output 2 |
| 3 | Q3 | Output 3 |
| 4 | Q4 | Output 4 |
| 5 | Q5 | Output 5 |
| 6 | Q6 | Output 6 |
| 7 | Q7 | Output 7 |
| 8 | GND | Ground |
| 9 | Q7’ | Serial Data Out (for cascading) |
| 10 | MR | Master Reset (active low) |
| 11 | SH_CP | Shift Register Clock Input |
| 12 | ST_CP | Storage Register Clock Input (latch) |
| 13 | OE | Output Enable (active low) |
| 14 | DS | Serial Data Input |
| 15 | Q0 | Output 0 |
| 16 | VCC | Power Supply |
Applications
LED and 7-segment display control
Multiplexing and demultiplexing
Digital output expansion for microcontrollers
Binary counting and timing circuits
Arduino-based projects and tutorials
Robotics and automation systems
Low-pin-count microcontroller interfaces
Signal routing and LED matrix displays
