An operational amplifier wherein each of the active elements is comprised of complimentary coupled pairs of insulated gate type field effect transistors is provided. A first active stage and a second active stage are coupled together to perform a predetermined transfer function. Each active element in the first and second stages are insulated gate type field effect transistors that are coupled in complementary pairs with the first stage and second stage being coupled to define mirror pairs.

A viscosimeter of the type employed for measuring the viscosity of dough, semi-liquid artificial resins, paints, lubricating oils and lacquers is disclosed. The viscosimeter includes a chamber capable of being sealed to retain fluid under pressure. A drive shaft extends through an opening in one wall of the chamber. The shaft is bent at an acute angle at a distance spaced inwardly from the wall of the chamber. A tubular extension connects the shaft with a ball or paddle, or other measuring surfa...

A high-gain, broad bandwidth differential operational amplifier is described. High-frequency response is increased by means of a feed-forward path, which bypasses the cascaded low-frequency differential stages at high frequencies and feeds the signal directly to a common base cascade output stage so that the rolloff of the low-frequency cascaded stages does not affect the high-frequency response of the amplifier.

Disclosed herein are a variety of operational circuits each including an operational amplifier with a plurality of feedback loops. Each of the feedback loops as well as the circuit inputs are connected to the operational amplifier through a high impedance input terminal forming part of a feedback loop switching circuit. The switching circuit includes a field effect transistor circuit, the high impedance input terminals comprising the gate electrodes of the field effect transistors. Signals in th...

A current mode operational rectifier has an output terminal connectable as a DC current source of a predetermined polarity, and comprises a high gain amplifier having an inverting input terminal for receiving an input signal current from an AC current source and two alternative transmission paths for providing full wave rectification. The first transmission path includes a first transistor having its base connected to the output terminal of the amplifier and its emitter and collector connected b...

A family of operational amplifiers are described which utilize only MOSFET transistors as the active devices. These operational amplifiers exhibit an infinite input impedance and zero input offset and bias currents. The circuits are capable of operating over a wide range of DC supply voltages at extremely low DC current drain. An operational amplifier is shown which operates from a single positive DC supply voltage and which handles a wide range of input common mode voltage swings including some...

An internally compensated monolithic integrated operational amplifier circuit has a differential input stage, balanced complementary common base stage, a complementary compound emitter-follower stage, and a push-pull output stage. The push-pull output stage includes complementary common emitter transistors, the base electrode of each transistor connected to a transistor connected in common base configuration. Bandwidth and slew rate are enhanced by a feed-forward capacitor connected between the ...

An operational amplifier is provided with a differential amplifier constructed by MOS transistors and a linear amplifier constructed by MOS transistors and coupled with the differential amplifier. The differential amplifier is supplied with first and second inputs. The output of the operational amplifier is derived from the output of the linear amplifier. A stabilizing circuit, which is coupled with the differential and linear amplifiers, stabilizes the output of the operational amplifier agains...

An operational amplifier which comprises a first amplifying circuit; a second amplifying circuit which is connected to the first amplifying circuit and carries out inverting amplification; a third amplifying circuit which is connected to the second amplifying circuit, carries out noninverting amplification and has a gain of substantially 1; a first feedback circuit which is connected between the output and input terminals of the second amplifying circuit and carries out phase-compensation; and a...

The invention relates to an operational amplifier (OA) with reduced offset voltage, particularly for A/D and D/A converters, S/H amplifiers, measuring instruments. The OA may also be used for applications where previously fast or precision OA's have been used. The basic circuitry of the OA consists of four resistors arranged in series, a fast OA B and preferably a precision OA A. The values of the resistors may be matched in such a way that the offset voltage of the OA B is totally eliminated or...