The 74HC85 are high-speed Si-gate CMOS devices and are pin compatible with low power Schottky TTL (LSTTL). They are specified in compliance with JEDEC standard no. 7A. The 74HC85 are 4-bit magnitude comparators that can be expanded to almost any length. They perform comparison of two 4-bit binary, BCD or other monotonic codes and present the three possible magnitude results at the outputs (QA>B, QA=B and QAB, IA=B and IAB = = LOW and IA=B = HIGH. For words greater than 4-bits, units can be cascaded by connecting outputs QA? and QA=B to the corresponding inputs of the significant comparator.
Features:-?
??Serial or parallel expansion without extra gating
??Magnitude comparison of any binary words
??Output capability: standard
??ICC category: MSI
Specifications:-
| Symbol | Parameter | Conditions | Typical | Unit | |
| ?HC | HCT | ||||
| tPHL/ tPLH | Propagation Delay ?to QAB 15 15 ns IA=B to QA=B 11 15 ns | CL = 15 pF; VCC = 5 V | ns | ||
| An, Bn to QA>B , QAB | 20 | 22 | ns | ||
| An, Bn to QA=B | 18 | 20 | ns | ||
| IA<B,, IA=B, IA>B to QA<B, QA>B | 15 | 15 | ns | ||
| A=B to QA=B | 11 | 15 | ns | ||
| CI | Input Capacitance | 3.5 | 3.5 | Pf | |
| CPD | Power Dissipation Capacitance per package | notes 1 and 2 | 18 | 20 | Pf |