The 74LS323 is an 8-Bit Shift/Storage Register with 3-state outputs. Its function is similar to the SN54/74LS299 except Synchronous Reset. Input parallel load and flip-flop outputs are multiplexed to minimize pin counting. For flip-flop separate inputs and outputs provided through Q0 and Q7. There are four operations modes are possible: Store, shift right, shift left and parallel load. All modes are activated on Low to high transition of the clock.
74LS323 Pin Configuration
| Pin Number | Pin Name | Description |
| 1, 19 | S0 and S1 | Input Pins for Mode Select |
| 3, 4 | OE1 & OE2 | 3-State Output Enable Inputs |
| 4, 5, 6, 7, 13, 14,15,16 | I/O0 – I/O7 | Parallel Output (3-State) or
Parallel Data Input |
| 8, 17 | Q0 and Q7 | Serial Output |
| 9 | SR | Synchronous Reset Input |
| 11 | DS0 | Serial Data Input for Right Shift |
| 18 | DS7 | Serial Data Input for Left Shift |
| 12 | CP | Clock Pulse (input) |
| 7 | VSS | Ground (- supply) |
| 14 | VCC | 5V, 10V, 15V +Supply Voltage |
Features/technical specifications of 74LS323 IC
- Max Supply Voltage: 5.25 V
- Operating Supply Voltage: 4.75 V to 5.25 V
- Type of Outputs: 3-State
- Temperature Range: 0 C to + 70 C
- Clock Frequency max: 25 MHz
- Propagation Delay Time Max: 39ns on 5V
- Com I/O for Reduced Pin Count
Alternatives shift Registers:
| Name | Type |
| 74LS379 | Quad Parallel Shift Register |
| CD4035 | 8-Bit Shift Register |
| 4014 | 4-Bit static Shift Register |
| 74HC595 | Dual 4 Bit Static Register |
| 74LS166 | 8-bit Shift Register |
| 74LS299 | 8 Bit Shift/Storage Register |
Where to use 74LS323 IC
The 74LS323 is an 8-bit universal Shift/Storage Register often used in projects where many LEDs have to be controlled through the Microcontroller. It can also be used to interface LCD screens because they can act as the data bit for the LCDs display.
Applications of 74LS323 8-bit shift Register
- Mostly used in Counters, Registers applications
- uses in Arithmetic-unit registers
- Serial-to-parallel/parallel-to-serial conversions
- Shift-left-shift-right registers
- Sequence generation applications
- Code conversion
- Control circuits
How to Use 74LS323
It is commonly used with microcontrollers or microprocessors to expand the GIPO functionalities. To choose the mode two function-select inputs (S0, S1) and two output-control inputs (Q0, Q7) can be used. A simple circuit is given below to show the application of 74LS323.
