An electrical system includes a power supply and an electrical circuit coupled to the power supply and including an operational amplifier. The operational amplifier includes an input stage and a pre-driver stage coupled to the input stage, wherein the pre-driver stage includes a first input terminal, a second input terminal, and a voltage supply terminal. The operational amplifier also includes an output stage with bipolar transistors coupled to the pre-driver stage. The pre-driver stage is configured to: detect a voltage differential across the first and second input terminals of the pre-driver stage; and provide an adjustable bias current based on the voltage differential.

A MOSFET has a current conduction path between source and drain terminals. A gate terminal of the MOSFET receives an input signal to facilitate current conduction in the current conduction path as a result of a gate-to-source voltage reaching a threshold voltage. A body terminal of the MOSFET is coupled to body voltage control circuitry that is sensitive to the voltage at the gate terminal of the MOSFET. The body voltage control circuitry responds to a reduction in the voltage at the gate terminal of the MOSFET by increasing the body voltage of the MOSFET at the body terminal of the MOSFET. As a result, there is reduction in the threshold voltage. The circuit configuration is applicable to amplifier circuits, comparator circuits and current mirror circuits.

A disclosed comparator includes a comparison circuit including a differential unit that compares an input signal with a reference signal and changes a level of a signal output to a first node in accordance with a result of comparison and an amplifier unit that includes a load element and outputs a signal in accordance with a potential of the first node to a second node, and a positive feedback circuit that is connected to the second node and a third node and changes a level of a signal at the third node at a rate higher than a change rate of a level of a signal at the second node in accordance with a change in a level of a signal at the second node.

The present technology relates to a comparator that can easily modify operating point potential of the comparator, and an imaging device. A pixel signal output from a pixel, and, a reference signal with changeable voltage are input to a differential pair. A current mirror connected to the differential pair, and a voltage drop mechanism allowed to cause a predetermined voltage drop is connected between a transistor that configures the differential pair, and a transistor that configures the current mirror. A switch is connected in parallel to the voltage drop mechanism. The present technology can be applied, for example, to an image sensor that captures an image.

The present disclosure provides a low dropout linear voltage regulator, including: an amplifier, configured to have a first input end receiving a reference voltage, a second input end configured to receive a feedback voltage, and an output end connected to a first node; an output transistor, having a control end connected to the first node, a first end connected to a first power source potential, and a second end connected to a second node and configured to provide an output voltage; a feedback circuit, connected to the second node and configured to provide the feedback voltage according to the output voltage; and a compensation circuit, comprising at least one of a first compensation amplifier, a second compensation amplifier and a first variable current source. The compensation circuit detects and suppresses a voltage transient generated when a load switching from light to heavy occurs at the second node.

An instrumentation amplifier that includes input capacitance cancellation is provided. The architecture includes programmable capacitors between the input stage and a current feedback loop of the instrumentation amplifier to cancel input capacitances from electrode cables and a printed circuit board at the front end. An on-chip calibration unit can be employed to calibrate the programmable capacitors and improve the input impedance.

An amplifier with an input stage comprising: a first current mirror; a first input differential pair; a first current source; a second current source; a second input differential pair, wherein the first input differential pair and the second input differential pair receive a reference voltage; a second current mirror; and a voltage control transmission circuit. An extra current path in the first current mirror is formed and a current flowing through the extra current path flows through the second current mirror to a ground when the reference voltage is higher than a first predetermined value. Also, an extra current path in the second current mirror is formed and a current flowing through the extra current path in the second current mirror flows to the first current mirror when the reference voltage is lower than a second predetermined value.

A device is provided. The device includes an operational amplifier, an output circuit, a first capacitor, and a second capacitor. The operational amplifier is configured to generate an output according to a feedback signal. The output circuit is configured to generate a first current signal in response to a supply voltage and the output of the operational amplifier. The first current signal includes a first ripple signal. The first capacitor and the second capacitor are coupled in parallel between the operational amplifier and the output circuit. The first capacitor is configured to receive the first current signal and feedback to the operational amplifier the first ripple signal.

The present technology relates to a comparator that can easily modify operating point potential of the comparator, and an imaging device. A pixel signal output from a pixel, and, a reference signal with changeable voltage are input to a differential pair. A current mirror connected to the differential pair, and a voltage drop mechanism allowed to cause a predetermined voltage drop is connected between a transistor that configures the differential pair, and a transistor that configures the current mirror. A switch is connected in parallel to the voltage drop mechanism. The present technology can be applied, for example, to an image sensor that captures an image.

An amplifying circuit includes a reference voltage generating circuit, a common-mode voltage conversion circuit, a common-mode negative feedback circuit, and an amplifying sub-circuit. The reference voltage generating circuit generates a first reference voltage, a second reference voltage, and a reference common-mode voltage according to a post-stage common-mode voltage. The common-mode voltage conversion circuit converts the pre-stage output differential signal into a differential input signal according to the reference common-mode voltage. The common-mode negative feedback circuit generates a control voltage to quickly establish a common-mode negative feedback of the amplifying sub-circuit, wherein the first reference voltage and the second reference voltage are used to cancel a baseline signal of the pre-stage output differential signal. The amplifying circuit can eliminate the baseline signal, convert the common-mode voltage and quickly establish the common-mode negative feedback.