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
performance. FACT Quiet Series™ features GTO™ output
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
0
–A
7
Data Register A Inputs
Data Register A Outputs
B
0
–B
7
Data Register B Inputs
Data Register B Outputs
CPAB,
CPBA
Clock Pulse Inputs
SAB, SBA Transmit/Receive Inputs
GTO™ is a trademark of National Semiconductor Corporation
FACT™ and FACT Quiet Series™ are trademarks of Fairchild Semiconductor Corporation
DS100326-1
IEEE/IEC
DS100326-2
September 1998
54ACTQ646
Quiet
Series
Octal
T
ransceiver/Register
with
3-ST
A
T
E
Outputs
© 1998 National Semiconductor Corporation DS100326 www.national.com