Zero-drift op amp offers low power without compromising accuracy

Linear Technology has announced the LTC2063 zero-drift op amp which draws just 1.3µA typ (2µA max) on a 1.8V supply. This micropower amplifier maintains uncompromised precision: maximum input offset voltage is 5µV at 25C, maximum drift is 0.06µV/C from –40C to 125C. Maximum input bias current is 15pA at 25C, and 100pA from –40C to 125C. These high precision input characteristics allow the use of large value feedback network resistors, keeping power consumption low without compromising accuracy, even at elevated temperature. Rail-to-rail inputs and outputs simplify single supply use and enhance dynamic range. An integrated EMI filter provides 114dB electromagnetic interference rejection at 1.8GHz. With low 1/f noise inherent to its zero-drift architecture the device is well suited for amplifying and conditioning low frequency sensor signals in high temperature industrial and automotive systems as well as portable and wireless sensor network applications. The device is available in SOT-23 and SC70 packages. The SC70 version includes a shutdown mode which reduces current consumption to just 90nA when the amplifier is not in use. This enables ultralow power duty cycled sensor applications. For example, a precision low duty cycle oxygen sensor circuit shown in the data sheet consumes less than 200nA average current. “The LTC2063 enables a whole new class of precision measurement solutions which can be placed anywhere,” stated Ross Yu, Dust Networks marketing manager. “Its ultralow power and high precision are a perfect companion for Dust Networks’ SmartMesh® wireless sensor networks, expanding the reach of precision measurements to places previously not practical.”