Zero-drift low-noise op amps suit sensor-interface apps

National Semiconductor has introduced the LMP2021 and LMP2022 zero-drift op amps featuring low input voltage noise - 11 nV/√Hz at a gain of 1,000 V/V - and high DC accuracy for instrumentation and sensor interface applications. The devices are claimed to enable, for the first time, the performance advantages of zero-drift amplifiers to be used in applications requiring high gain and low sub-15 nV/√Hz noise.

Key specifications include 0.004 µV/°C of input offset voltage drift (TCV_OS), with a typical V_OS of 0.4 µV. Both devices operate from 2.2 to 5.5 V and offer a gain bandwidth of 5 MHz while consuming only 1.1 mA per channel. Operating temperature range is -40°C to 125°C.

Continuous-correction circuitry auto zeroes the input offset error voltage, enabling uninterrupted accuracy over time and temperature, with high CMRR and PSRR, as well as removal of the 1/f voltage error component. Integrated EMI suppression filters provide an EMI rejection ratio of 79 dB.

The single LMP2021 is supplied in 5-pin SOT23 and 8-pin SOIC packages, and the dual LMP2022 is supplied in 8-pin SOIC and 8-pin MSOPs. The parts are available now and priced at $1.35 and $1.90 ea/1,000, respectively.

National Semiconductor, 1-800-272-9959, www.national.com

Related links:
LMP2021 zero-drift op amp information page
LMP2022 zero-drift op amp information page
WEBENCH Sensor Designer Tool
ADC161S626 16-bit ADC information page