General Description

These octal 3-STATE bus drivers are designed to provide the designer with flexibility in implementing a bus interface with memory, microprocessor, or communication systems, and are low power dissipation versions of the DM74ALS240A and DM74ALS241A. The output 3-STATE gating control is organized into two separate groups of four buffers. The DM74ALS1240A control inputs symmetrically enable the respective outputs when set logic LOW. The 3- STATE circuitry contains a feature that maintains the buffer outputs in 3-STATE (high impedance state) during power supply ramp-up or ramp-down. This eliminates bus glitching problems that arise during power-up and power-down.

Features

■ Advanced oxide-isolated, ion-implanted Schottky TTL process

■ Switching response specified into 500Ω and 50 pF load

■ Switching response specifications guaranteed over full temperature and VCC supply range

■ PNP input design reduces input loading

■ Low power dissipation version

■ Low level drive current: 74ALS = 16 mA