NTE945

NTE945 Integrated Circuit Operational Amp 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: D Guaranteed Bias Currents as Low as 50pA D Maximum Offset Currents Down to 15pA D Operates from Supplies of ±3V to ±20V D Supply Current Only 300µA at ±20V Absolute Maximum Ratings: Supply Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±20V Power Dissipation (Note 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 500mW Differential Input Current (Note 2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±10mA Input Voltage (Note 3) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±15V Output Short−Circuit Duration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Indefinite Operating Temperature Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0° to +70°C Storage Temperature Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −65° to +150°C Lead Temperature (Durin Soldering, 10sec) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +300°C Note 1. The maximum junction temperature is +70°C. For operating at elevated temperatures, the NTE945 must be derated based on a thermal resistance of +150°C/W, junction−to−ambient, or +45°C/W, junction−to−case. Note 2. The inputs are shunted with back−to−back diodes for overvoltage protection. Therefore, excessive current will flow if a differential input voltage in excess of 1V is applied between the inputs unless some limiting resistance is used. Note 3. For supply voltages less than ±15V, the absolute maximum input voltage is equal to the supply voltage. Electrical Characteristics: (TA = −0° to +55°C, ±5V ≤ VS ≤ ±20V unless otherwise specified) Parameter Input Offset Voltage Input Offset Current Input Bias Current Input Resistance Supply Current Large Signal Voltage Gain Output Voltage Swing Input Voltage Range Common Mode Rejection Ratio Supply Voltage Rejection Ratio Pin Connection Diagram (Top View) Test Conditions TA = +25°C TA = +25°C TA = +25°C TA = +25°C TA = +25°C VS = ±15V, VOUT = ±10V, RL ≥ 10kΩ VS = ±15V, RL = 10kΩ VS = ±15V TA = +25°C Min − − − − − − 1 − 20 15 ±13 ±13 80 80 Typ − − − − − − − − − − − − − − Max 10 15 50 100 150 250 − 0.8 − − − − − − Unit mV mV pA pA pA pA GΩ mA V/mV V/mV V V dB dB Compensation Output 5 6 4 V (−) V (+) 7 3 Non−Invert Input Balance 8 1 Balance 2 Invert Input .370 (9.39) Dia Max .335 (8.52) Dia Max .177 (4.5) Max .492 (12.5) Min .018 (0.45) Dia Typ 2 1 45° 8 7 3 4 5 .200 (5.06) Dia 6 .032 (0.82)