The LM111, LM211, LM311 are voltage comparators that have low input currents. They are also designed to operate over a wide range of supply voltages: from standard ±15V operational amplifier supplies down to the single +5V supply used for IC logic. Their output is compatible with RTL-DTL and TTL as well as MOS circuits and can switch voltages up to +50V at output currents as high as 50mA.
