The PGA855 is a high-bandwidth programmable gain instrumentation amplifier with fully differential outputs. The PGA855 is equipped with eight binary gain settings, from an attenuating gain of 0.125V/V to a maximum of 16V/V, using three digital gain selection pins. The output common-mode voltage can be independently set using the VOCM pin.

The PGA855 architecture is optimized to drive inputs of high-resolution, precision analog-to-digital converters (ADCs). The output-stage power supplies are decoupled from the input stage to protect the ADC or downstream device against overdrive damage.

The super-beta input transistors offer an impressively low input bias current, which in turn provides a very low input current noise density of 0.3pA/√Hz, making the PGA855 a versatile choice for virtually any sensor type. The low-noise current-feedback front-end architecture offers excellent gain flatness even at high frequencies, making the PGA855 an excellent high-impedance sensor readout device. Integrated protection circuitry on the input pins handles overvoltages up to ± 40V beyond the power-supply voltages.