Document
HD74HC688
8-bit Magnitude Comparator
REJ03D0643–0200 (Previous ADE-205-529)
Rev.2.00 Mar 30, 2006
Description
The HD74HC688 compares bit for bit two 8-bit words and indicates whether or not they are equal. The P=Q output indicates equality when it is low.
A single active low enable is provided to facilitate cascading of several packages and enable comparison of words greater than 8-bits.
This device is useful in memory block decoding applications, where memory block enable signals must be generated from computer address information.
Features
• High Speed Operation: tpd (P or Q to Output) = 17 ns typ (CL = 50 pF) • High Output Current: Fanout of 10 LSTTL Loads
• Wide Operating Voltage: VCC = 2 to 6 V • Low Input Current: 1 µA max
• Low Quiescent Supply Current: ICC (static) = 4 µA max (Ta = 25°C) • Ordering Information
Part Name
Package Type
Package Code (Previous Code)
Package Abbreviation
HD74HC688P
DILP-20 pin (JEDEC)
PRDP0020AC-B (DP-20NEV)
P
HD74H.