The LTC 1540 is an ultralow power, single comparator with built-in reference. The comparator's features include less than 0.6A supply current over the commercial temperature range, a 1.182V 2% reference, programmable hysteresis and TTL/CMOS outputs that sink and source current. The reference output can drive a bypass capacitor of up to 0.01F without oscillation. The comparator operates from a single 2V to 11V supply or a dual 1V to 5.5V supply. Comparator hysteresis is easily programmed by using two resistors and the HYST pin. Each comparator's input operates from the negative supply to within 1.3V of the positive supply. The comparator output stage can continuously source up to 40mA. By eliminating the cross-conducting current that normally occur when the comparator changes logic states, power supply glitches are eliminated. The LTC1540 is available in the 8-pin MSOP and SO packages.