An operational amplifier 1 is provided with differential amplifier 2, replica amplifier 3, voltage-current converting circuit 4, reference current source 5 and comparator 6. Differential amplifier 2 includes P-channel MOS transistors PT1 and PT2, gate and drain electrodes of which are connected to each other to function as loads, and N-channel MOS transistors NT1, NT2 and NT3. Replica amplifier 3 is identical in structure to differential amplifier and also includes P-channel MOS transistors PT11...

An operational amplifier includes: a differential input section for generating a first signal corresponding to a differential voltage between two input signals; an amplifying section for amplifying the first signal in voltage to generate second and third complementary signals; a first MOS transistor connected between a first supply voltage and an output node, a conduction state of the first MOS transistor being controlled in accordance with the second signal; a second MOS transistor connected be...

An operation amplifier 1 for driving an liquid crystal panel is constructed of: differential stage circuits 2, 3, drive stage circuits 4, 5, output transistors 11 to 14, switching means for switching the connections of the differential stage circuits 2, 3 and the drive stage circuits 4, 5, and a middle-potential side power source 10. These differential stage circuits 2, 3 and drive stage circuits 4, 5 are operated between the high-potential side power source 8 and the low-potential side power so...

An operational amplifier having two differential input stages. A first one of the stages comprises a pair of first input transistors and another one of such stages comprises a pair of second input transistors. The second input transistors are complementary in type to the first input transistors. A comparator is fed by a sense signal and a reference signal, such sense signal being related to at least one of a non-inverting and an inverting input signal fed to the operational amplifier. The compar...

An operational amplifier according to an embodiment of the invention includes: a control signal input terminal receiving a digital control signal from an external device; first and second transistors as a differential pair of a differential amplifier circuit; a constant current circuit supplying a predetermined current to the differential pair; a first resistor provided between the constant current circuit and the first transistor and involving a first potential difference; and a second resistor...

An operational amplifier includes a differential amplifier circuit provided at an input stage and an amplifier circuit at a post stage. In the differential amplifier circuit, first and third bipolar transistors are PNP-type bipolar transistors and Darlington-connected. An inverting input terminal is connected to the base terminal of the first bipolar transistor. The first and third bipolar transistors and second and fourth bipolar transistors construct an input differential pair. First and secon...

An operational amplifier and use of an operational amplifier is provided that includes an input differential amplifier, which is connected to a first input and to a second input and a differential output stage, which is connected to the input differential amplifier and a first output and a second output. The differential output stage has a first branch with two first transistors, whose drain and/or collector are connected to one another and to the first output. The differential output stage has ...

A disclosed operational amplifier includes: a pair of differential stages; a cascode amplifier stage; and an output stage. A threshold voltage of an output transistor constituting the output stage is higher than a threshold voltage of other transistors.

An operational control for use with a ventilation, heating, or air conditioning unit of a vehicle, that can be actuated by a turn knob comprises: a guide member for being attached to and manipulated by a turn knob, the guide member defining a guiding groove; an adjusting lever for actuating a Bowden cable to which the adjusting lever is linked, the adjusting lever being mounted adjacent the guide member to pivot; a guide pin attached to the adjusting lever for extending into the guiding groove f...

An operational amplifier capable of supplying a large power approximate to a power supply voltage to a load resistance and of rendering the current consumption relative to the power supply voltage small when a signal is not issued. The operational amplifier comprises a first differential amplifying stage, a first amplifying stage, a first level shifting stage, a second differential amplifying stage, a second amplifying stage, a second level shifting stage, and outputting stage, a first phase com...