NXP 4000 Series Logic Devices
- NXP HEF4585BP, 652, The HEF4585B is a 4-bit magnitude comparator that compares two 4-bit words, A & B, & 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 & B0 to B3) with A3 & B3 being the most significant inputs. Three outputs are provided: A greater than B (QA>B), A less than B (QA<B) & A equal to B (QA=B). Three expander inputs (IA>B, IA<B, & 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 & IA<B = LOW. All other cascaded devices have IA=B & IA<B connected to QA=B & 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. NXP HEF4585BP, 652 4-Bit Magnitude Comparator DIL-16