An operational amplifier having a differential amplifier section, a level shifting section, an output section and a bias section. In the operational amplifier, the bias section senses any changes in the power voltage and controls the level shifting of the level shifting section with the sensed change in the power voltage so as to remove an offset component in the output voltage of the differential amplifier section which arises from the power voltage change.

An operational amplifier includes a PNP differential amplifier operable for low common mode input voltages and an NPN differential amplifier operable for high common mode input voltages so that the operational amplifier is operable over a range of common mode input voltages that includes substantially the positive and negative supply voltages.

An operational amplifier includes an input stage, an output stage including first, second and third NPN output transistors, and an intermediate stage. The first NPN output transistor sources load current to an output terminal while the second and third output transistors sink load current therefrom. The output of the intermediate stage is coupled to the base of the third NPN transistor and, via a resistor, to the base of the second NPN transistor. A first Miller capacitor is coupled between the ...

An operational amplifier includes a differential input stage and a composite differential amplifier second stage. The second stage includes first and second NPN transistors which receive at their base terminals the differential output of the first stage. The emitters of these transistors are coupled respectively to the base electrodes of first and second PNP transistors which act, in conjunction with a current mirror circuit, to produce a single ended output which is applied to the operational a...

An apparatus for operational analysis of computing devices which, when coupled to the address, data, and control buses of a computer, displays a representation of a selectable subgroup of the bus signals on a bit map display for each occurrence of a selectable condition. The bits of the least and most significant halves of the selected subgroup define the horizontal and vertical coordinates of a display pixel activated upon occurrence of the selectable condition. Selectable groups are address an...

Two input stages (10,12) are interconnected so that their input common mode voltage ranges to one side of signal ground are combined to provide a common mode voltage range substantially equal to the supply voltage. One stage has N-channel differential input transistors (N1,N2), while the other stage has P-channel differential input transistors (P3,P4). The input current branches of the stages are interconnected by current mirror transistors (N6,N7) so that signal current is shared. The output (2...

An operational amplifier includes an input stage, an output stage including first, second and third NPN output transistors, and an intermediate stage. The output stage is driven by a thermal current having a positive temperature coefficient so as to keep the gain of the output stage substantially constant over temperature. Thus, the amplifiers Miller loop stability will also remain substantially constant over temperature.

In a system for monitoring the condition of a machine by vibration analysis, including at least one vibration sensor in operative contact with the machine for sensing machine vibrations, and for providing a vibration signal at its output, a sampling device connected to the output of the vibration sensor for sampling, amplifying and digitizing the signal obtained from the vibration sensor, a frequency analyzer arranged to receive the sampled and digitized signal from the sampling device, and a pa...

A d.c. high voltage operational amplifier. The output of a conventional power operational amplifier is converted to a.c. which is stepped up by a transformer and then rectified to provide a high voltage d.c. output. Appropriate feedback circuitry is utilized to stabilize the overall operational amplifier against oscillation and provide substantially perfect linearity between the input and output voltages of the high voltage operational amplifier when incorporating negative feedback.

The front end of an operational amplifier having an improved controlled slew rate and high gain current output capabilities. The amplifier includes a slew enhancement or large signal stage connected in parallel to a normal front end or small signal stage. The small signal stage supplies a transconductance output which is approximately linearly related to the input until its slew rate limit. The slew enhancement stage is designed to provide slew current when the small signal stage reaches its sle...