Low-power, Zero-drift Instrumentation Amplifier Provides Accuracy and Extended Battery Life in Portables
Texas Instruments Incorporated introduced a low-power zero-drift instrumentation amplifier. The device is presented as having the lowest quiescent current and lowest input bias current versus competitive products, as well as desirable power-to-noise ratio, low offset voltage/drift and 1.8 V operation. The INA333 is suited for a variety of precision, low-power applications such as portable medical, handheld instrumentation, weigh scales and data acquisition. It uses the company’s zero-drift technology, which incorporates a proprietary switched-capacitor notch filter to eliminate chopping noise and provide very low input voltage noise of 50 nV/rt-Hz. The device features a versatile three op amp architecture, 75 uA of quiescent current and operation on power supplies as low as 1.8 V. Low offset voltage of 25 uV and offset drift of 0.1 uV/C enhances accuracy and long-term stability. It also features low input bias current of 200 pA. Special filters have been integrated in series with the inputs of the INA333 to reduce radio frequency (RF) interference.