AD629BRZ

The AD629BRZ is one member of the AD629 series.The AD629 is a difference amplifier with a very high input, common-mode voltage range. It is a precision device that allows the user to accurately measure differential signals in the presence of high common-mode voltages up to ±270 V.The AD629 can replace costly isolation amplifiers in applications that do not require galvanic isolation. The device operates over a ±270 V common-mode voltage range and has inputs that are protected from common-mode or differential mode transients up to ±500 V.

Features of the AD629BRZ are:(1)improved replacement for: INA117P and INA117KU; (2)±270 V common-mode voltage range; (3)input protection to:±500 V common mode,±500 V differential mode; (4)wide power supply range (±2.5 V to ±18 V); (5)±10 V output swing on ±12 V supply; (6)1 mA maximum power supply current.The AD629 has low offset, low offset drift, low gain error drift, low common-mode rejection drift, and excellent CMRR over a wide frequency range.

The absolute maximum ratings of the AD629BRZ can be summarized as:(1)Ssupply voltage:±18 V;(2)input voltage range, continuous:±300 V;(3)common-mode and differential, 10 sec:±500 V;(4)storage temperature range:-65 to +150;(5)operating temperature range:-55 to +125;(6)lead temperature:300.Stresses above those listed under Absolute Maximum Ratings may cause permanent damage to the device. This is a stress rating only; functional operation of the device at these or any other conditions above those listed in the operational sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.The AD629 is a unity gain, differential-to-single-ended amplifier (diff amp) that can reject extremely high common-mode signals (in excess of 270 V with 15 V supplies). It consists of an operational amplifier (op amp) and a resistor network.To reduce output drift, the op amp uses super beta transistors in its input stage. The input offset current and its associated temperature coefficient contribute no appreciable output voltage offset or drift, which has the added benefit of reducing voltage noise because the corner where 1/f noise becomes dominant is below 5 Hz.