LM11C

The LM11C is a precision, low drift operational amplifier providing the best features of existing FET and Bipolar op amps.Implementation of super gain transistors allows reduction of input bias currents by an order of magnitude over earlier devices such as the LM308A. Offset voltage and drift have also been reduced. Although bandwidth and slew rate are not as great as FET devices, input offset voltage, drift and bias current are inherently lower, particularly over temperature. Power consumption is also much lower, eliminating warm-up stabilization time in critical applications.

Features of the LM11C are:(1)low input offset voltage: 100 V; (2)low input bias current: 17 pA; (3)low input offset current: 0.5 pA; (4)low input offset voltage drift: 1.0 V/; (5)long-term stability: 10 V/year; (6)high common mode rejection: 130 dB.Offset balancing is provided, with the range determined by an external low resistance potentiometer.Compensation is provided internally, but external compensation can be added for improved stability when driving capacitiveloads.The precision characteristics of the LM11C make this device ideal for applications such as charge integrators, analog memories, electrometers,active filters, light meters and logarithmic amplifiers.

The absolute maximum ratings of the LM11C can be summarized as:(1)power supply voltage:40V;(2)storage temperature range:-55 to 125;(3)operating junction temperature:85;(4)differential input current (note 1):±10mA;(5)output short circuit duration (note 2):indefinite;(6)power dissipation (note 3):500mW.Due to the extremely low input bias currents of this device,it may be tempting to remove the bias current compensation resistor normally associated with a summing amplifier configuration. Direct connection of the inputs to a low impedance source or ground should be avoided when supply voltages greater than approximately 3.0 V are used. The potential problem involves reversal of one supply which can cause excessive current to flow in the second supply.Possible destruction of the IC could result if the second supply is not current limited to approximately 100 mA or if bypass capacitors greater than 1.0F are used in the supply bus.