The LM324 series are low−cost, quad operational amplifiers with
true differential inputs. They have several distinct advantages over
standard operational amplifier types in single supply applications. The
quad amplifier can operate at supply voltages as low as 3.0 V or as
high as 32 V with quiescent currents about one−fifth of those
associated with the MC1741 (on a per amplifier basis). The common
mode input range includes the negative supply, thereby eliminating the
necessity for external biasing components in many applications. The