Texas Instruments PGA855 Programmable-Gain Instrumentation Amplifier
Texas Instrument PGA855 Programmable-Gain Instrumentation Amplifier is a high-bandwidth programmable gain instrumentation amplifier with fully differential outputs. The PGA855 has 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 Texas Instruments PGA855 architecture is optimized to drive inputs of high-resolution, precision analog-to-digital converters (ADCs) with sampling rates up to 1MSPS without needing an additional ADC driver. The output-stage power supplies (LVSS/LVDD) are decoupled from the input stage. The devices can be connected to the power supplies of the ADC to protect the ADC or a downstream device against overdrive damage.
The super-beta input transistors offer an impressively low input bias current, providing 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.
Features
- Eight pin-programmable binary gains
- G (V/V) = ⅛, ¼, ½, 1, 2, 4, 8, and 16
- 1ppm/°C (max) at G = 1V/V low gain error drift
- Fully differential outputs
- Independent output power-supply pins to allow for ADC input overdrive protection
- Output common-mode control
- Faster signal processing
- A wide bandwidth of 10MHz at all gains
- 35V/µs high slew rate
- 500ns to 0.01%, 950ns to 0.0015% settling time
- Input stage noise of 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
- Output-stage supply range
- Single supply: 4.5V to 36V
- Dual supply: ±2.25V to ±18V
- Specified temperature range of -40°C to +125°C
- 3mm × 3mm VQFN small package
Applications
- Factory automation and control
- Analog input module
- Data acquisition (DAQ)
- Test and measurement
- Semiconductor test
Simplified Application
Related Development Tool
Texas Instruments PGA855EVM Evaluation Module
Evaluates the PGA855 high-precision programmable-gain amplifier with differential outputs.