Integrated Device Technology, Inc.

MILITARY AND COMMERCIAL TEMPERATURE RANGES

MAY 1992

©1992 Integrated Device Technology, Inc.

7.19

DSC-4618/2

®

IDT54/74FCT821A/B/C

IDT54/74FCT823A/B/C

IDT54/74FCT824A/B/C

IDT54/74FCT825A/B/C

HIGH-PERFORMANCE

CMOS BUS INTERFACE

REGISTERS

FEATURES:

• Equivalent to AMD’s Am29821-25 bipolar registers in

pinout/function, speed and output drive over full tem-

perature and voltage supply extremes

• IDT54/74FCT821A/823A/824A/825A equivalent to

FAST

™ speed

• IDT54/74FCT821B/823B/824B/825B 25% faster than

FAST

• IDT54/74FCT821C/823C/824C/825C 40% faster than

FAST

• Buffered common Clock Enable (

EN) and asynchronous

Clear input (

CLR)

• Clamp diodes on all inputs for ringing suppression

• CMOS power levels (1mW typ. static)

• TTL input and output compatibility

• CMOS output level compatible

• Substantially lower input current levels than AMD’s

bipolar Am29800 series (5

µA max.)

• Product available in Radiation Tolerant and Radiation

Enhanced versions

• Military product compliant to MIL-STD-883, Class B

DESCRIPTION:

The IDT54/74FCT800 series is built using an advanced

dual metal CMOS technology.

The IDT54/74FCT820 series bus interface registers are

designed to eliminate the extra packages required to buffer

existing registers and provide extra data width for wider

address/data paths or buses carrying parity. The IDT54/

74FCT821 are buffered, 10-bit wide versions of the popular

‘374 function. The IDT54/74FCT823 and IDT54/74FCT824

are 9-bit wide buffered registers with Clock Enable (

EN) and

Clear (

CLR) – ideal for parity bus interfacing in high-perform-

ance microprogrammed systems. The IDT54/74FCT825 are

8-bit buffered registers with all the ‘823 controls plus multiple

enables (

interface, e.g.,

CS, DMA and RD/WR. They are ideal for use

All of the IDT54/74FCT800 high-performance interface

family are designed for high-capacitance load drive capability,

while providing low-capacitance bus loading at both inputs

and outputs. All inputs have clamp diodes and all outputs are

designed for low-capacitance bus loading in high-impedance

state.

FUNCTIONAL BLOCK DIAGRAMS

IDT54/74FCT821/823/825

IDT54/74FCT824

The IDT logo is a registered trademark of Integrated Device Technology, Inc.

FAST is a trademark of National Semiconductor Co.

2608 cnv* 01

2608 cnv* 02

D

CP Q

Q

CL

D

CP Q

Q

CL

EN

CLR

CP

OE

D

CP Q

Q

CL

D

CP Q

Q

CL

EN

CLR

CP

OE

1