Nat Semi LM339N QUAD DIFFERENTIAL COMPARATOR (Pack of 3)

Manufactured by National Semiconductor - DIP14 package

These devices consist of four independent voltage comparators that are designed to operate from a single power supply over a wide range of voltages.
Operation from dual supplies also is possible, as long as the difference between the two supplies is 2 V to 36 V, and VCC is at least 1.5 V more positive than the input common-mode voltage. Current drain is independent of the supply voltage. The outputs can be connected to other open-collector outputs to achieve wired-AND relationships.