Instrumentation amp cuts out interference

Edited by the Electronicstalk editorial team Jan 15, 2003

The AD8221 instrumentation amplifier provides the highest common-mode rejection over frequency of any instrumentation amplifier available in an MSOP.

The AD8221 instrumentation amplifier provides the highest CMR (common-mode rejection) over frequency of any instrumentation amplifier available in an MSOP package, which is half the size of a traditional SOIC package.

CMR is the most important attribute of an instrumentation amplifier, and the AD8221 provides breakthrough performance of 90dB (at unity gain) to 10kHz.

Also, the CMR of the device improves as the gain increases.

The high CMR holds system errors to a minimum by rejecting common mode voltage noise - to 10 kHz and beyond - from sources including motors, repair equipment, switching power supplies and high-frequency medical equipment, Along with excellent noise immunity, the AD8221 also features low input offset voltage (100uV), low input offset voltage drift (0.8uV/degC), low gain drift (10ppm/degC at unity gain), and low noise (7nV/(rt)Hz RTI noise at 1kHz).

The AD8221 operates at a quiescent current of 1mA over a resistor-programmable gain range of 1 to 1000.

The AD8221's small size makes it ideal for applications requiring multiple high-performance channels in a limited amount of space.

Medical applications include equipment for monitoring ECGs, respiration, vital signs, and pacemakers, portable defibrillators, and surgical support.

Industrial applications include programmable logic controllers, universal drives, sensor modules, and motor controllers.

Instrumentation and data acquisition applications include multichannel I/O boards, portable gas detectors, flow meters, and automotive test equipment.

The AD8221 is sampling now in an 8-pin MSOP, is specified over the standard industrial temperature range of -40 to +85C, and is priced at $2.25 per unit in 1000-piece quantities.