IDT74FCT646 Datasheet, PDF (1/8 Pages) Integrated Device Technology – FAST CMOS OCTAL TRANSCEIVER/REGISTER

®
Integrated Device Technology, Inc.
FAST CMOS OCTAL
TRANSCEIVER/REGISTER
IDT54/74FCT646
IDT54/74FCT646A
IDT54/74FCT646C
FEATURES:
• IDT54/74FCT646 equivalent to FAST™ speed;
• IDT54/74FCT646A 30% faster than FAST
• IDT54/74FCT646C 40% faster than FAST
• Independent registers for A and B buses
• Multiplexed real-time and stored data
• IOL = 64mA (commercial) and 48mA (military)
• CMOS power levels (1mW typical static)
• TTL input and output level compatible
• CMOS output level compatible
• Available in 24-pin (300 mil) CERDIP, plastic DIP, SOIC,
CERPACK and 28-pin LCC
• Product available in Radiation Tolerant and Radiation
Enhanced Versions
• Military product compliant to MIL-STD-883, Class B
DESCRIPTION:
The IDT54/74FCT646/A/C consists of a bus transceiver
with 3-state D-type flip-flops and control circuitry arranged for
multiplexed transmission of data directly from the data bus or
from the internal storage registers.
G The IDT54/74FCT646/A/C utilizes the enable control ( )
and direction (DIR) pins to control the transceiver functions.
SAB and SBA control pins are provided to select either real
time or stored data transfer. The circuitry used for select
control will eliminate the typical decoding glitch that occurs in
a multiplexer during the transition between stored and real-
time data. A LOW input level selects real-time data and a
HIGH selects stored data.
Data on the A or B data bus or both can be stored in the
internal D flip flops by LOW-to-HIGH transitions at the
appropriate clock pins (CPAB or CPBA) regardless of the
select or enable control pins.
FUNCTIONAL BLOCK DIAGRAM
G
DIR
CPBA
SBA
CPAB
SAB
1 OF 8 CHANNELS
A1
A REG
1D
C1
B REG
1D
C1
B1
TO 7 OTHER CHANNELS
The IDT logo is a registered trademark of Integrated Device Technology, Inc.
FAST is a registered trademark of National Semiconductor Co.
MILITARY AND COMMERCIAL TEMPERATURE RANGES
©1992 Integrated Device Technology, Inc.
7.18
2536 drw 01
MAY 1992
DSC-4626/2
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