SN74ALS677A

This SN74ALS677A 16-bit address comparator simplifies addressing of memory boards and/or other peripheral devices. The four P inputs are normally hardwired with a preprogrammed address. An internal decoder determines what input information applied to the A inputs must be low or high to cause a low state at the Y output. For example, a positive-logic bit combination of 0111 (decimal 7) at the P input determines that inputs A1 through A7 must be low and that inputs A8 through A16 must be high to cause the output to go low. Equality of the address applied at the A inputs to the preprogrammed address is indicated by the output being low.

SN74ALS677A features an enable (G) input. When G is low, the device is enabled. When G is high, the device is disabled and the output is high, regardless of the A and P inputs. The SN74ALS677A is characterized for operation from 0°C to 70°C.