Overview: DATA SHEET www.onsemi.com Octal Bus Buffer MC74VHC244, MC74VHCT244A The MC74VHC244/MC74VHCT244A is an advanced high speed CMOS octal bus buffer fabricated with silicon gate CMOS technology.
The device is a noninverting 3−state buffer, and has two active−low output enables. This device is designed to be used with 3−state memory address drivers, etc.
The MC74VHC244 inputs are compatible with standard CMOS levels while the MC74VHCT244A inputs are compatible with TTL levels. The MC74VHCT244A device can be used as a level converter for interfacing 3.3 V to 5.0 V, because it has full 5.0 V CMOS level output swings.
The internal circuit is composed of three stages, including a buffer output which provides high noise immunity and stable output. The MC74VHC244 and MC74VHCT244A inputs tolerate voltages up to 5.5 V, allowing the interface of 5 V systems to 3 V systems.
The MC74VHCT244A output structures provide protection when VCC = 0 V. These output structures help prevent device destruction caused by supply voltage − input/output voltage mismatch, battery backup, hot insertion, etc.
