General Description

The DS1648/DS3648 and DS1678/DS3678 are quad 2-input multiplexers with TRI-STATE outputs designed to drive

the large capacitive loads (up to 500 pF) associated with

MOS memory systems. A PNP input structure is employed

to minimize input currents so that driver loading in large

memory systems is reduced. The circuit employs Schottkyclamped transistors for high speed and TRI-STATE outputs

for bus operation.

The DS1648/DS3648 has a 15X resistor in series with the

outputs to dampen transients caused by the fast-switching

output. The DS1678/DS3678 has a direct, low impedance

output for use with or without an external resistor.

Features

Y TRI-STATE outputs interface directly with system-bus

Y Schottky-clamped for better ac performance

Y PNP inputs to minimize input loading

Y TTL compatible

Y High-speed capacitive load drivers

Y Built-in damping resistor (DS1648/DS3648 only)