74AC521 鈥?74ACT521 8-Bit Identity Comparator
November 1988
Revised October 2000
74AC521 鈥?74ACT521
8-Bit Identity Comparator
General Description
The AC/ACT521 is an expandable 8-bit comparator. It
compares two words of up to eight bits each and provides a
LOW output when the two words match bit for bit. The
expansion input I
A
=
B
also serves as an active LOW enable
input.
Features
s
I
CC
reduced by 50%
s
Compares two 8-bit words in 6.5 ns typ
s
Expandable to any word length
s
20-pin package
s
Outputs source/sink 24 mA
s
ACT521 has TTL-compatible inputs
Ordering Code:
Order Number
74AC521SC
74AC521SJ
74AC521MTC
74AC521PC
74ACT521SC
74ACT521SJ
74ACT521MTC
74ACT521PC
Package Number
M20B
M20D
MTC20
N20A
M20B
M20D
MTC20
N20A
Package Description
20-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-013, 0.300 Wide
20-Lead Small Outline Package (SOP), EIAJ TYPE II, 5.3mm Wide
20-Lead Thin Shrink Small Outline Package (TSSOP), JEDEC MO-153, 4.4mm Wide
20-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide
20-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-013, 0.300 Wide
20-Lead Small Outline Package (SOP), EIAJ TYPE II, 5.3mm Wide
20-Lead Thin Shrink Small Outline Package (TSSOP), JEDEC MO-153, 4.4mm Wide
20-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide
Device also available in Tape and Reel. Specify by appending suffix letter 鈥淴鈥?to the ordering table.
Logic Symbols
Connection Diagram
IEEE/IEC
Pin Descriptions
Pin Names
A
0
鈥揂
7
B
0
鈥揃
7
T
A
=
B
O
A
=
B
Description
Word A Inputs
Word B Inputs
Expansion or Enable Input
Identity Output
FACT錚?is a trademark of Fairchild Semiconductor Corporation.
漏 2000 Fairchild Semiconductor Corporation
DS009964
www.fairchildsemi.com