GENERAL DESCRIPTION

The AD8251 is an instrumentation amplifier with digitally programmable gains that has GΩ input impedance, low output noise, and low distortion, making it suitable for interfacing with sensors and driving high sample rate analog-to-digital converters (ADCs). It has a high bandwidth of 10 MHz, low THD of −110 dB, and fast settling time of 785 ns (maximum) to 0.001. Offset drift and gain drift are guaranteed to 1.8 μV/°C and 10 ppm/°C, respectively, for G = 8. In addition to its wide input common voltage range, it boasts a high common-mode rejection of 80 dB at G = 1 from dc to 50 kHz. The combination of precision dc performance coupled with high speed capabilities makes the AD8251 an excellent candidate for data acquisition. Furthermore, this monolithic solution simplifies design and manufacturing and boosts performance of instrumentation by maintaining a tight match of internal resistors and amplifiers.

FEATURES

Small package: 10-lead MSOP

Programmable gains: 1, 2, 4, 8

Digital or pin-programmable gain setting

Wide supply: ±5 V to ±15 V

Excellent dc performance

High CMRR: 98 dB (minimum), G = 8

Low gain drift: 10 ppm/°C (maximum)

Low offset drift: 1.8 μV/°C (maximum), G = 8

Excellent ac performance

Fast settling time: 785 ns to 0.001 (maximum)

High slew rate: 20 V/μs (minimum)

Low distortion: −110 dB THD at 1 kHz, 10 V swing

High CMRR over frequency: 80 dB to 50 kHz (minimum)

Low noise: 18 nV/√Hz, G = 8 (maximum)

Low power: 4.1 mA

APPLICATIONS

Data acquisition

Biomedical analysis

Test and measurement