Sunnyvale, Calif.—Forget about the converter or software for now: a good sensor signal chain starts with a very good front-end op amp. The Maxim MAX44251 dual device is the latest op amp to strive for near-ideal performance, along with the higher supply-rail voltages needed by industrial-level applications. It operates from a 2.7 to 27 V supply, and includes initial offset below 6 µV (maximum) along with a proprietary autocorrelating, autozero calibration approach which keeps drift below 19 nV/ ° C (again, maximum) over the -40 to +125 ° C range.
Gain bandwidth is 10 MHz, while power dissipation is 1.15 mA per channel. Input-referred noise is 5.9 nV/vHz, which the vendor claims is the lowest available for a high-voltage, autozeroing component. Other critical specifications include power supply-rejection ratio (PSRR), common-mode rejection ratio (CMRR), and large-signal voltage gain (AVOL ) at 135 dB each, (+25 ° C). In addition, the IC offers additional RF immunity, critical where so many industrial and medical installations are in RF-heavy environments.
Package, pricing, and availability : The MAX44251 is available in a 8-lead SOT23 and µMAX packages, and is priced at $1.48 (1000 pieces); it is available now.
For more information : contact Maxim Integrated Products, http://www.maxim-ic.com.