View lm111x datasheet:

Philips Semiconductors Linear Products Product specification LM111/211/311/ Voltage comparator LM311B DESCRIPTION PIN CONFIGURATION The LM111 series are voltage comparators that have input currents D, FE, N PACKAGES approximately a hundred times lower than devices like the µA710. They are designed to operate over a wider range of supply voltages; from standard ±15V op amp supplies down to a single 3V supply. 1 8 GND V+ Their output is compatible with RTL, DTL, and TTL as well as MOS circuits. Further, they can drive lamps or relays, switching voltages INPUT 2 7 OUTPUT + up to 50V at currents as high as 50mA. – INPUT 3 6 BAL/STROBE Both the inputs and the outputs of the LM111 series can be isolated from system ground, and the output can drive loads referred to V– 4 5 BA