DESCRIPTION

· The MM74HC688 is an 8-bit magnitude comparator (equality detector) using advanced silicon-gate CMOS technology.

· It compares two 8-bit words bit by bit and indicates equality with a LOW P/Q output.

· Features a single active low enable for cascading multiple packages to compare words larger than 8 bits.

· Ideal for memory block decoding applications, generating memory block enable signals from computer address information.

· Output can drive 10 low power Schottky equivalent loads.

· Functionally and pin-compatible with the 74LS688.

· All inputs are protected from static discharge damage with diodes to VCC and ground.

FEATURES

· Typical propagation delay: 20 ns.

· Wide power supply range: 2V to 6V.

· Low quiescent current: 80 µA (74 Series).

· Large output current: 4 mA (74 Series).

· Equivalent to HC521.

APPLICATIONS

· Memory block decoding in computer systems.

· Generation of memory block enable signals from address information.

· Cascading for comparing larger data words.