Low-noise wide-bandwidth precision programmable-gain amplifier

The PGA848 is a wide-bandwidth, low-noise programmable gain instrumentation amplifier for differential-to-single-ended conversion. The PGA848 is equipped with eight decade (scope) gain settings, from an attenuating gain of 0.5V/V to a maximum of 100V/V. Gain is set using three digital gain selection pins.

The PGA848 architecture is optimized to drive inputs of high-resolution, precision analog-to-digital converters (ADCs) with sampling rates up to 1MSPS without additional ADC drivers. The output-stage power supplies are decoupled from the input stage to protect the ADC or downstream devices 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. This capability makes the PGA848 a versatile choice for virtually any sensor type. The low-noise current-feedback front-end architecture offers exceptional gain flatness even at high frequencies, making the PGA848 an excellent high-impedance sensor readout device. Integrated protection circuitry on the input pins handles overvoltages of up to ±40V beyond the power-supply voltages.