Capacitive door handle sensor comprising at least one transmission electrode and a reception electrode, an operational amplifier configured as a charge amplifier and connected to the reception electrode, a switch for charge transfer, a first and a second switch for discharging the two operational amplifier inputs and, a capacitor arranged between the output and the inverting input of the operational amplifier, and a control unit for controlling and evaluating the measurement, wherein the control unit comprises a reference potential switching output which is connected to a terminal of the switch and is configured to selectively control a capacitance measurement between the transmission electrodes and the reception electrode or between the reception electrode and ground. Furthermore, methods for setting different operating modes are claimed.

Capacitive door handle sensor comprising at least one transmission electrode and a reception electrode, an operational amplifier configured as a charge amplifier and connected to the reception electrode, a switch for charge transfer, a first and a second switch for discharging the two operational amplifier inputs and, a capacitor arranged between the output and the inverting input of the operational amplifier, and a control unit for controlling and evaluating the measurement, wherein the control unit comprises a reference potential switching output which is connected to a terminal of the switch and is configured to selectively control a capacitance measurement between the transmission electrodes and the reception electrode or between the reception electrode and ground. Furthermore, methods for setting different operating modes are claimed.

An analog front-end includes a (1-1)-th charge amplifier configured to differentially amplify a first and second sensing signals provided to a (1-1)-th input terminal and a (1-2)-th input terminal, respectively, and output a (1-1)-th differential signal. A (1-2)-th charge amplifier is configured to differentially amplify the second sensing signal and a third sensing signal provided to a (1-3)-th input terminal and a (1-4)-th input terminal, respectively, and output a (1-2)-th differential signal. A second charge amplifier is configured to differentially amplify the (1-1)-th differential signal and the (1-2)-th differential signal provided to a (2-1)-th input terminal and a (2-2)-th input terminal, respectively, and output a (2-1)-th differential signal and a (2-2)-th differential signal. A demodulation circuit is configured to filter the (2-1)-th differential signal and the (2-2)-th differential signal and output demodulated differential signals. An analog-to-digital converter is configured to output a sensing value based on the demodulated differential signals.

An analog front-end includes a (1-1)-th charge amplifier configured to differentially amplify a first and second sensing signals provided to a (1-1)-th input terminal and a (1-2)-th input terminal, respectively, and output a (1-1)-th differential signal. A (1-2)-th charge amplifier is configured to differentially amplify the second sensing signal and a third sensing signal provided to a (1-3)-th input terminal and a (1-4)-th input terminal, respectively, and output a (1-2)-th differential signal. A second charge amplifier is configured to differentially amplify the (1-1)-th differential signal and the (1-2)-th differential signal provided to a (2-1)-th input terminal and a (2-2)-th input terminal, respectively, and output a (2-1)-th differential signal and a (2-2)-th differential signal. A demodulation circuit is configured to filter the (2-1)-th differential signal and the (2-2)-th differential signal and output demodulated differential signals. An analog-to-digital converter is configured to output a sensing value based on the demodulated differential signals.

Describe is a buffer which comprises: a differential source follower coupled to a first input and a second input; first and second current steering devices coupled to the differential source follower; and a current source coupled to the first and second current steering devices. The buffer provides high supply noise rejection ratio (PSRR) together with high bandwidth.

A microphone assembly includes a transducer element and a processing circuit. The processing circuit includes an analog-to-digital converter (ADC) configured to receive, sample and quantize a microphone signal generated by the transducer element to generate a corresponding digital microphone signal. The processing circuit includes a feedback path including a digital loop filter configured to receive and filter the digital microphone signal to provide a first digital feedback signal and a digital-to-analog converter (DAC) configured to convert the first digital feedback signal into a corresponding analog feedback signal. The processing circuit additionally includes a summing node at the transducer output configured to combine the microphone signal and the analog feedback signal.

A microphone assembly includes a transducer element and a processing circuit. The processing circuit includes an analog-to-digital converter (ADC) configured to receive, sample and quantize a microphone signal generated by the transducer element to generate a corresponding digital microphone signal. The processing circuit includes a feedback path including a digital loop filter configured to receive and filter the digital microphone signal to provide a first digital feedback signal and a digital-to-analog converter (DAC) configured to convert the first digital feedback signal into a corresponding analog feedback signal. The processing circuit additionally includes a summing node at the transducer output configured to combine the microphone signal and the analog feedback signal.

An oscillator includes a resonator, sustaining circuit and detector circuit. The sustaining circuit receives a sense signal indicative of mechanically resonant motion of the resonator generates an amplified output signal in response. The detector circuit asserts, at a predetermined phase of the amplified output signal, one or more control signals that enable an offset-reducing operation with respect to the sustaining amplifier circuit.

An oscillator includes a resonator, sustaining circuit and detector circuit. The sustaining circuit receives a sense signal indicative of mechanically resonant motion of the resonator generates an amplified output signal in response. The detector circuit asserts, at a predetermined phase of the amplified output signal, one or more control signals that enable an offset-reducing operation with respect to the sustaining amplifier circuit.

An apparatus includes a photodetector configured to generate an electrical current based on received illumination. The apparatus also includes a capacitor transimpedance amplifier (CTIA) unit cell having (i) an amplifier configured to receive the electrical current and a reference voltage, (ii) a feedback capacitor coupled in parallel across the amplifier, and (iii) a reset switch coupled in parallel across the feedback capacitor. The apparatus further includes an event detector configured to sense a high-energy event affecting the photodetector. In addition, the apparatus includes a switchable clamp coupled across inputs of the amplifier, where the event detector is configured to close the switchable clamp in response to sensing the high-energy event.