MM54HC85/MM74HC85
4-Bit Magnitude Comparator
General Description
The MM54HC85/MM74HC85 is a 4-bit magnitude comparator
that utilizes advanced silicon-gate CMOS technology. It
is designed for high speed comparison of two four bit words.
This circuit has eight comparison inputs, 4 for each word;
three cascade inputs (AkB, AlB, AeB); and three decision
outputs (AkB, AlB, AeB). The result of a comparison
is indicated by a high level on one of the decision outputs.
Thus it may be determined whether one word is ``greater
than,'' ``less than,'' or ``equal to'' the other word. By connecting
the outputs of the least significant stage to the cascade
inputs of the next stage, words of greater than four bits
can be compared. In addition the least significant stage
must have a high level applied to the AeB input, and a low
level to the AkB, and AlB inputs.
The comparator's outputs can drive 10 low power Schottky
TTL (LS-TTL) equivalent loads, and is functionally, and pin
equivalent to the 54LS85/74LS85. All inputs are protected
from damage due to static discharge by diodes to VCC and
ground.
Features
Y Typical propagation delay: 27 ns
Y Wide operating voltage range: 2±6V
Y Low input current: 1 mA maximum
Y Low quiescent current: 80 mA maximum (74HC Series)
Y Output drive capability: 10 LS-TTL loads