In one implementation, a circuit can include a reference pin and an operational amplifier that can include an output pin, an inverting input pin and a non-inverting input pin. The inverting input pin can be electrically coupled to the output pin via a first impedance and to the reference pin via a second impedance. The non-inverting input pin can be electrically coupled to the reference pin via a third impedance and can be configured to receive a detection signal. The reference pin can be configured to receive a detection reference signal associated with the detection signal.

Systems and methods for amplifying an input signal include amplifier circuitry, an itail connection coupled between a positive voltage circuitry and the negative voltage circuitry and operable to generate an itail voltage corresponding to a greater of the positive voltage input signal (Vp) and the negative voltage input signal (Vn), a first resistor rgp disposed to receive the itail voltage and a first voltage corresponding to Vp, and a second resistor rgn disposed to receive the itail voltage and a second voltage corresponding to Vn. A first current output node is coupled to the output of rgp and operable to output a positive output current (Ioutp) corresponding to the current flowing through rgp, and a second current output is coupled to the output of rgn and operable to output a negative output current (Ioutn) corresponding to the current flowing through rgn.

An electronic circuit for a micro-electro-mechanical systems gyroscope is disclosed. The electronic circuit includes a current buffer, a transimpedance amplifier coupled with the current buffer, and a plurality of transistors. An inverting input terminal of the current buffer and a non-inverting input terminal of the current buffer are connected with a plurality of first resistors. The inverting input terminal of the current buffer is connected with a source of one of the plurality of transistors, and the non-inverting input terminal of the current buffer is connected with a source of another one of the plurality of transistors. The plurality of first resistors are connected to a ground. The current buffer is configured to isolate a load in the micro-electro-mechanical systems gyroscope from the transimpedance amplifier.

A buffering circuit arranged to buffer a sensed signal of a pixel circuit includes: an amplifying circuit, a first switching unit and a capacitor. The amplifying circuit has a control terminal of coupled to an output terminal of the pixel circuit, a first terminal arranged to output a buffered sensed signal, and a second terminal coupled to a reference voltage. The first switching unit has a first terminal coupled to the control terminal of the amplifying circuit and a second terminal coupled to the first terminal of the amplifying circuit. The capacitor has a first terminal coupled to the control terminal of the amplifying circuit and a second terminal coupled to the first terminal of the amplifying circuit. The first switching unit is turned on during a first stage and turned off during a second stage. The amplifying circuit generates the buffered sensed signal during the second stage.

The semiconductor device includes a Hall element, a first differential pair, a second differential pair, an output amplifier circuit, and a voltage divider circuit. The Hall element outputs a signal that is dependent on stress to be applied to a semiconductor substrate to the first differential pair. The voltage divider circuit divides a voltage into a divided voltage having a voltage dividing ratio that is dependent on the stress. The first differential pair outputs a first current based on the signal. The second differential pair outputs a second current based on the divided voltage and a reference voltage. The output amplifier circuit outputs a voltage based on the first and second currents. A gain of the output amplifier circuit is approximated by a sum of a difference between stress dependence coefficients of transconductances of the first and second differential pairs and a stress dependence coefficient of the voltage dividing ratio.

An isolation amplifier includes an input circuit at high voltage potential with an input for a measurement signal to be transmitted, an input circuit configuration providing a coupling section signal representing the measurement signal, and a high-voltage-side control unit for driving the input circuit, a galvanically isolating coupling section for the potential-free transmission of the coupling section signal to an output circuit at low-voltage potential with an output circuit configuration for generating an output signal from the transmitted coupling section signal, an output for the output signal and at least one low-voltage-side control unit for generating control signals, input elements for inputting control commands and/or parameters into the high-voltage-side control unit, a low-voltage-side arrangement of all the input elements provided for the parameterization of the high-voltage-side control unit, exclusively in a low-voltage circuit, and a galvanically isolating control channel for transmitting the parameters for driving the input circuit.

An embodiment of an amplifier circuit includes first, second, and third amplifiers. The first and second amplifiers, each of which can be a respective operational amplifier or a respective transconductance amplifier, are configured to amplify a differential input signal with a non-inverting gain. And the third amplifier, which can be an operational amplifier or a transconductance amplifier, is configured to cause the first and second amplifiers to amplify a common-mode input signal with a gain that is less than unity. The third amplifier can also be configured to cause the first and second amplifiers to generate a common-mode output voltage that is substantially independent of the common-mode input voltage. Consequently, in addition to presenting a high input impedance and a low noise factor, such an amplifier circuit has a configurable common-mode output voltage and has a lower common-mode gain (e.g., less than unity, approaching zero) than other non-inverting differential amplifiers.

A circuit for use in a system that includes a detector, wherein the circuit comprises an input terminal to receive a detector signal from the detector external to the circuit, the detector signal to include an error charge corresponding to a leakage current. The circuit further comprises an amplifier coupled to the input terminal to receive input signals corresponding to the detector signal, including the error charge applied to an input of the amplifier. The circuit further comprises a feedback path coupled across the amplifier, wherein the feedback path comprises a first switch coupled across a leakage resistor and to a leakage capacitor for discharging a feedback compensation charge from the leakage capacitor and onto the input of the amplifier to substantially cancel the error charge.

In an embodiment, a differential buffer may include a first input stage that compares a non-inverting portion of an input signal alternately to a non-inverting portion of an output and to an inverting portion of the output. Another embodiment of the differential buffer may also include a second input stage that compares the inverting portion of the input signal alternately to the inverting portion of the output signal and to the non-inverting portion of the output signal. Other embodiments of the differential buffer may include a feedback chopper switch that transfers the non-inverting portion of the output signal and the inverting portion of the output signal to the first input stage and to the second input stage.

Embodiments of the present disclosure provide a current amplification circuitry and a driving method thereof, and a fingerprint detection device. The current amplification circuitry includes a voltage control circuit, a plurality of first current amplification circuits, and a second current amplification circuit. The voltage control circuit provides a voltage control signal to the plurality of first current amplification circuits. The first current amplification circuit includes a current mirror, and the current mirror is coupled to a voltage input terminal, the voltage control circuit, and a first input terminal of the second current amplification circuit. The first current amplification circuit amplifies a current from the voltage input terminal according to the voltage control signal provided by the voltage control circuit, and provides the amplified current to the second current amplification circuit. The second current amplification circuit is coupled to the voltage input terminal via a second input terminal and amplifies the amplified current.