A transceiver that may be implemented in low-voltage differential signaling (LVDS) transmission system or a multipoint LVDS transmission system, and corresponding systems are disclosed herein. The transceiver can filter a common-mode component of a differential input signal input into the transceiver while maintaining a high impedance for a differential-mode component of the differential input signal. The transceiver utilizes teeter-totter circuitry to maintain the high impedance for the differential-mode component of the differential input signal.

A capacitive-coupled chopper instrumentation amplifier includes a first chopper, a first gain stage, a capacitive isolation stage electrically coupled between inputs of the first gain stage and the first chopper, a second gain stage, a second chopper electrically coupled between outputs of the first gain stage and inputs of the second gain stage, clamping circuitry electrically coupled between the inputs of the first gain stage and a reference voltage rail, and a controller. The controller is configured to (a) detect a change in a first common-mode voltage exceeding a threshold value, the first common-mode voltage being a common-mode voltage at the inputs of the amplifier, and (b) in response to detecting the change in the first common-mode voltage exceeding the threshold value, cause the clamping circuitry to clamp the inputs of the first gain stage to the reference voltage rail.

The present disclosure relates to chopper amplifier circuits featuring inherent chopper ripple suppression.

A read-out circuitry for acquiring a multi-channel biopotential signal, comprises: a plurality of read-out signal channels, each receiving an input signal from a unique signal electrode; a reference channel receiving a reference signal from a reference electrode; wherein each read-out signal channel and the reference channel comprises a channel amplifier connected to receive the input signal in a first input node and with an output node connected to a second input node via a channel feedback loop; wherein each signal channel amplifier comprises a capacitor between the second input nodes of the signal channel amplifier and the reference channel amplifier, and wherein each signal channel feedback loop and the reference channel feedback loop comprise a filter.

An electronic device is provided. The electronic device includes an earphone including a first impedance component, a signal generator configured to output a first alternating current (AC) signal, a first circuit including at least one first analog device having an impedance component electrically coupled to the first impedance component, and configured to receive the first AC signal and output a first detection signal including a voltage component corresponding to the first impedance component, and at least one processor configured to generate at least one piece of biometric information, based on the first detection signal, and output the at least one piece of biometric information.

An amplifier circuit includes a circuit path of serially connected complementary type transistors. First and second feedback loops include a loop amplifier, the transistors of the circuit path and a corresponding resistor.

An apparatus for determining properties of an uncharacterized downhole fluid. The apparatus comprises an oscillation driver circuit comprising an amplifier having an output and an input, a feedback loop between the output and input of an amplifier or a logic gate, an electromechanical resonator disposed within the feedback loop such that a the resonator is driven by the oscillation driver circuit, wherein a resonant frequency of the resonator defines an oscillation frequency of the oscillator circuit, and a switch device for causing the oscillator circuit to stop driving the resonator, which thereby enables observation of a decay rate of the oscillation of the electromechanical resonator within the uncharacterized fluid. The electromechanical resonator is enclosed in a conductive layer to protect the resonator against capacitive effects of the downhole fluid.

A signal measurement apparatus and signal measurement method are provided. The signal measurement apparatus includes an amplifier configured to receive a differential voltage signal, amplify the received differential voltage signal, and output the amplified differential voltage signal, a controller configured to output a control signal to control a switching circuit in response to a signal value of the amplified differential voltage signal satisfying a condition, and wherein the switching circuit is configured to change connections between input terminals of the amplifier and paths along which the differential voltage signal is transmitted, based on the control signal.

A conversion circuit is arranged for converting an ion detection current (i.sub.D) produced by an ion detector into an ion detection signal (P). The conversion circuit comprises: an input stage for converting the ion detection current (i.sub.D) into an ion detection voltage (V.sub.D), an output stage for converting the ion detection voltage into the detection signal (P), the output stage being arranged for drawing a first current dependent on the ion detection voltage, and a supplementary stage for providing a second current (i.sub.S) dependent on the ion detection voltage to the output stage.

The second current may be substantially equal to the first current.

The disclosure provides a gas detector with an ionizing device for producing ions depending on a gas to be detected. The gas detector includes a catcher for receiving the electrical current produced by the ions, and a measuring device with an electrical measuring resistor. The electrical measuring resistor produces an electrical measuring potential from the current and is surrounded, at least in part, by an electrical shield resistor, denoted by R.sub.T. The same potentials, up to a deviation of at most 25%, are applied in the longitudinal direction of the electrical measuring resistor to mutually opposed regions of the electrical measuring resistor and the electrical shield resistor.