PGA855中文資料德州儀器數(shù)據(jù)手冊(cè)PDF規(guī)格書

1 Features

? Eight pin-programmable binary gains

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

? Low gain error drift: 1 ppm/°C (max) at G = 1 V/V

? Fully differential outputs

– Independent output power-supply pins to allow

for ADC input overdrive protection

– Output common-mode control

? Faster signal processing:

– Wide bandwidth: 10 MHz at all gains

– High slew rate: 35 V/μs

– Settling time:

500 ns to 0.01, 950 ns to 0.0015

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

– Filter option to achieve better SNR

? Input overvoltage protection to ±40 V beyond

supplies

? Input-stage supply range:

– Single supply: 8 V to 36 V

– Dual supply: ±4 V to ±18 V

? Output-stage supply range:

– Single supply: 4.5 V to 36 V

– Dual supply: ±2.25 V to ±18 V

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

? Small package: 3-mm × 3-mm VQFN

2 Applications

? Factory automation and control

? Analog input module

? Data acquisition (DAQ)

? Test and measurement

? Semiconductor test

3 Description

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 0.125 V/V

to a maximum of 16 V/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) with sampling rates up to 1 MSPS

without the need for an additional ADC driver.

The output-stage power supplies (LVSS/LVDD) are

decoupled from the input stage and can be connected

to power supplies of the ADC 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 0.3 pA/√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 ±40 V beyond the powersupply

voltages.