描述 Description

The PGA849 is a wide-bandwidth, low-noise programmable gain instrumentation amplifier for differential-to-single-ended conversion. The PGA849 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 PGA849 architecture is optimized to drive inputs of high-resolution, precision analog-to-digital converters (ADCs) with sampling rates up to 1MSPS without the need for an additional ADC driver. 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 PGA849 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 PGA849 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.

特性 Features

Differential to single-ended conversion

Eight pin-programmable binary gains

G (V/V) = ?, ?, ?, 1, 2, 4, 8, and 16



Low gain error drift: 2ppm/°C (max)

Faster signal processing:

Wide bandwidth: 10MHz at all gains

High slew rate: 35V/μs

Settling time: 500ns to 0.01%, 950ns to 0.0015%

Input stage noise: 7.8nV/√Hz at G = 16V/V

Filter option to achieve better SNR



Input overvoltage protection to ±40V beyond supplies

Input-stage supply range:

Single supply: 8V to 36V

Dual supply: ±4V to ±18V



Independent output power-supply pins

Output-stage supply range:

Single supply: 4.5V to 36V

Dual supply: ±2.25V to ±18V



Specified temperature range: -–40°C to +125°C

Small package: 3mm × 3mm QFN