The OP777 is a precision single supply amplifier featuring micropower operation and rail-to-rail output ranges. This amplifier provides improved performance over the industry-standard OP07 with 15 V supplies and offers the further advantage of true single supply operation down to 2.7 V, and smaller package footprint than any other high-voltage precision bipolar amplifier. Outputs are stable with capacitive loads of over 1000 pF. Supply current is less than 300 A per amplifier at 5 V. 500 series resistors protect the inputs, allowing input signal levels to exceed either power supply rail by up to 3 V without causing phase reversal of the output signal or causing damage to the amplifier. The proprietary fabrication process yields a very low-voltage noise corner frequency under 10 Hz, greatly improving the low-frequency noise performance of the OP07 and similar amplifiers. The specially fabricated input PNP transistors operate with very low input bias currents while allowing operation with large differential voltages, eliminating a common limitation of many precision amplifiers and enabling application of the OP777 in precision comparator and rectifier circuits. This large differential voltage capability also further reduces the need for external protection devices such as clamping diodes.