The HEF4585B is a 4-bit magnitude comparator that compares two 4-bit words, A and B, and determines whether A is greater than B, A is equal to B, or A is less than B. Each word has four parallel inputs (A0 to A3 and B0 to B3) with A3 and B3 being the most significant inputs. Three outputs are provided: A greater than B (QA>B), A less than B (QA<B) and A equal to B (QA=B). Three expander inputs (IA>B, IA<B, and IA=B) allow cascading of the devices, to compare 8, 12, 16, ..., bits without external gates.
To operate a single device or a device in the least significant position in a cascaded chain, the expander inputs are connected as follows: IA=B = IA>B = HIGH and IA<B = LOW. All other cascaded devices have IA=B and IA<B connected to QA=B and QA<B respectively of the previous (less significant) device in the chain, while input IA>B is connected to a HIGH. Operation is not restricted to pure binary code; the devices will work with any monotonic code.
It operates over a recommended VDD power supply range of 3 V to 15 V referenced to VSS (usually ground). Unused inputs must be connected to VDD, VSS, or another input.
- DIL-16 Package
- Large operating supply range 3 to 15V
- Low power consumption
Logic IC Base Number |
4585 |
Logic IC Function |
4-Bit magnitude comparator |
Package/Case |
DIL-16 |
Operating Temperature Range |
-40 to +85°C |