Description:

The NTE945 is a precision, high input impedance operational amplifier in an 8−Lead Metal Can type package designed for applications requiring extremely low input current errors. This device uses supergain transistors in a Darlington input stage to get input bias currents that are equal to high−quality FET amplifiers−even in limited temperature range operation.

Unlike most other internally compensated amplifiers, the MOS compensation capacitor is protected to prevent catastrophic failure from overvoltage spikes on the supplies.

The low current error of this amplifier makes possible many designs that were previously impractical with monolithic amplifiers. It will operate from 100mΩ source resistances, introducing less error than general purpose amplifiers with 10kΩ sources, Integrators with worst case drifts less than 10µV/sec and analog time delays in excess of one day can also be made using capacitors no larger than 1µF.

Features:

• Guaranteed Bias Currents as Low as 50pA

• Maximum Offset Currents Down to 15pA

• Operates from Supplies of ±3V to ±20V

• Supply Current Only 300µA at ±20V