LM324 consist of four independent high-gain frequency-compensated operational amplifiers (op-amp) that are designed specifically to operate from a single supply over a wide range of voltages. The LM324 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 output voltage range also includes the negative power supply voltage.