MC74HC595ADG

Shift Registers Overview

The MC74HC595ADG is an 8-bit serial-input/serial or parallel-output shift register with latched 3-state outputs, manufactured by onsemi. It consists of an 8-bit shift register and an 8-bit D-type latch. The device operates within a supply voltage range of 2.0 V to 6.0 V and supports a maximum clock frequency of 30 MHz at 4.5 V. Propagation delays range from 28 ns to 42 ns depending on the specific signal path and temperature. It features low input current of 1.0 µA and high noise immunity. The component is housed in a SOIC-16 package.

Shift Registers Feature Summary

• Features independent shift and latch clocks for stable parallel output during shifting operations
• Provides three-state parallel outputs compatible with CMOS, NMOS, and TTL loads
• Includes asynchronous reset functionality for the shift register portion only
• Directly interfaces with SPI serial data ports on CMOS microprocessors

Shift Registers Applications

• Serial-to-parallel data conversion
• Parallel output expansion for microcontrollers
• SPI interface peripheral control
• Data receiver circuits

Shift Registers Procurement Notes

Verify the ordering suffix 'DG' corresponds to the SOIC-16 package and Pb-Free status as specified in the official datasheet. Confirm RoHS compliance and lead-free marking requirements for your assembly process. Ensure the selected variant matches the required operating voltage range and thermal characteristics for your specific application environment.

Shift Registers Selection Notes

Select this component when interfacing with standard CMOS logic families requiring 3-state outputs. It is suitable for applications needing direct SPI connection without additional level shifting. Consider the HC series for wider voltage operation compared to HCT variants. Verify package availability and moisture sensitivity level requirements for surface mount assembly processes.

Shift Registers Part Context

This part belongs to the MC74HC595A family of high-performance silicon-gate CMOS logic devices. It offers improved propagation delays and lower quiescent power compared to previous generations. The device is designed for compatibility with standard logic families while maintaining CMOS low power dissipation characteristics. It is widely used in digital systems requiring serial data processing and parallel output distribution.

Shift Registers Replacement Considerations

MC74HC595ADR2G (Tape & Reel version of same function)

Shift Registers FAQ

Does the Output Enable pin affect the serial output SQH?

No, the Output Enable pin only controls the three-state parallel outputs QA-QH. The serial output SQH remains active regardless of the Output Enable state.

What is the function of the Reset pin?

The Reset pin is an active-low, asynchronous input that resets only the shift register contents. It does not affect the data stored in the output latch register.

Can unused inputs be left floating?

No, unused inputs must always be tied to an appropriate logic voltage level (either GND or VCC) to ensure proper functionality and prevent excessive current consumption.