MC74HC244ADW

Overview

The MC74HC244ADW is an octal 3-state noninverting buffer and line driver manufactured by onsemi. It utilizes high-performance silicon-gate CMOS technology and operates within a voltage range of 2.0 to 6.0 V. The device features two active-low output enables and provides drive capability for 15 LSTTL loads. Propagation delays vary from 96 ns at 2.0 V to 15 ns at 6.0 V. It is housed in a SOIC-20 wide package.

Feature Summary

• Octal 3-state noninverting buffer design with dual active-low output enables
• High noise immunity characteristic of CMOS devices
• Direct interface capability to CMOS, NMOS, and TTL logic families
• Compatible with standard CMOS outputs and LSTTL outputs using pullup resistors

Applications

• Memory address drivers
• Clock drivers
• Bus-oriented systems

Procurement Notes

Verify the specific ordering suffix against the manufacturer's official documentation to confirm package type and shipping quantity. Ensure the component meets RoHS compliance requirements if applicable to your manufacturing standards. Confirm that the supply chain source provides valid traceability for the semiconductor lot codes.

Selection Notes

Select this component when interfacing between different logic families requiring high-speed buffering. The HC series offers a wider operating voltage range compared to HCT variants. Verify input compatibility with the driving source, noting that pullup resistors may be required for LSTTL compatibility.

Part Context

This part belongs to the MC74HC244A family of octal buffers. It shares pinout compatibility with LS244 devices. The datasheet also covers the MC74HCT244A variant, which is optimized for 5 V operation and TTL input compatibility. Both variants share similar functional descriptions but differ in electrical specifications.

Replacement Considerations

MC74HC244ADWG

FAQ

How are unused inputs handled?

Unused inputs must always be tied to an appropriate logic voltage level, either GND or VCC.

What is the function of the Enable pins?

Enable A and Enable B are active-low controls. When low, outputs are enabled; when high, outputs assume a high-impedance state.