54ACTQ646

Quiet Series Octal Transceiver/Register with 3-STATE

Outputs

General Description

The ACTQ646 consist of registered bus transceiver circuits,

with outputs, D-type flip-flops, and control circuitry providing

multiplexed transmission of data directly from the input bus

or from the internal storage registers. Data on the A or B bus

will be loaded into the respective registers on the

LOW-to-HIGH transition of the appropriate clock pin (CPAB

or CPBA). The four fundamental handling functions available

are illustrated in

Figures 1, 2, 3, 4.

The ACTQ utilizes FSC Quiet Series technology to guaran-

tee quiet output switching and improved dynamic threshold

control and undershoot corrector in addition to a split ground

bus for superior performance.

Features

n Guaranteed simultaneous switching noise level and

dynamic threshold performance

n Independent registers for A and B busses

n Multiplexed real-time and stored data transfers

n 300 mil slim dual-in-line package

n Outputs source/sink 24 mA

n Faster prop delays than the standard AC/ACT646

n 4 kV minimum ESD immunity

n Standard Microcircuit Drawing (SMD) 5962-9219601

Logic Symbols

Pin Descriptions

Pin Names

Description

A

Data Register A Inputs

Data Register A Outputs

B

Data Register B Inputs

Data Register B Outputs

CPAB,

CPBA

Clock Pulse Inputs

SAB, SBA

Transmit/Receive Inputs

DS100326-1

IEEE/IEC

DS100326-2

September 1998

© 1998 National Semiconductor Corporation

DS100326

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