Abstract: An amplifier includes a first input branch and a second input branch that form a differential input stage and a current mirror connected to the differential input. The current mirror is governed as a function of a common mode feedback signal applied to a control node of the current mirror. A second, amplification, stage includes a branch flowing through which is a current, which is a function of the current that flows in the first input branch, and is in turn connected to a first output branch. A capacitive element is coupled between the control node and the second stage. The circuit is symmetrical with respect to the input stage.

Abstract: A comparator circuit including: a first node and a second node, which receive a first current and a second current, respectively; a first current mirror, which includes a first load transistor and a first output transistor; and a second current mirror, which includes a second load transistor and a second output transistor.

Abstract: An amplifier circuit, for a capacitive acoustic transducer defining a sensing capacitor that generates a sensing signal as a function of an acoustic signal, has a first input terminal and a second input terminal, which are coupled to the sensing capacitor and: a dummy capacitor, which has a capacitance corresponding to a capacitance at rest of the sensing capacitor and a first terminal connected to the first input terminal; a first buffer amplifier, which is coupled at input to the second input terminal and defines a first differential output of the circuit; a second buffer amplifier, which is coupled at input to a second terminal of the dummy capacitor and defines a second differential output of the circuit; and a feedback stage, which is coupled between the differential outputs and the first input terminal, for feeding back onto the first input terminal a feedback signal, which has an amplitude that is a function of the sensing signal and is in phase opposition with respect thereto.

Abstract: A sensing circuit includes: a follower transistor, having a control terminal; a follower terminal for connection to a load; a bias-current generator, coupled to the follower terminal; and a feedback stage, configured to control the bias-current generator as a function of an input signal on the control terminal of the follower transistor.

Abstract: An amplifier circuit, for a capacitive acoustic transducer defining a sensing capacitor that generates a sensing signal as a function of an acoustic signal, has a first input terminal and a second input terminal, which are coupled to the sensing capacitor and: a dummy capacitor, which has a capacitance corresponding to a capacitance at rest of the sensing capacitor and a first terminal connected to the first input terminal; a first buffer amplifier, which is coupled at input to the second input terminal and defines a first differential output of the circuit; a second buffer amplifier, which is coupled at input to a second terminal of the dummy capacitor and defines a second differential output of the circuit; and a feedback stage, which is coupled between the differential outputs and the first input terminal, for feeding back onto the first input terminal a feedback signal, which has an amplitude that is a function of the sensing signal and is in phase opposition with respect thereto.

Abstract: An electronic circuit for amplifying signals with two components in phase quadrature, which includes: a feedback amplifier with a feedback capacitor; a switch that drives charging and discharging of the feedback capacitor; an additional capacitor; and a coupling circuit, which alternatively connects the additional capacitor in parallel to the feedback capacitor or else decouples the additional capacitor from the feedback capacitor. The switch opens at a first instant, where a first one of the two components assumes a first zero value; the coupling circuit decouples the additional capacitor from the feedback capacitor in a way synchronous with a second instant, where the first component assumes a second zero value.

Abstract: An amplifier includes a first input branch and a second input branch that form a differential input stage and a current mirror connected to the differential input. The current mirror is governed as a function of a common mode feedback signal applied to a control node of the current mirror. A second, amplification, stage includes a branch flowing through which is a current, which is a function of the current that flows in the first input branch, and is in turn connected to a first output branch. A capacitive element is coupled between the control node and the second stage. The circuit is symmetrical with respect to the input stage.

Abstract: An analog input voltage is converted to a digital code by, generating a first set of confirmed bits based on a first series of comparisons of an output of a digital-to-analog converter with the analog input voltage and generating a second set of confirmed bits based on a second series of comparisons of the output of the digital-to-analog converter with the analog input voltage. The first set of confirmed bits is independent of the second series of comparisons. The bits of the digital output code corresponding to the analog input voltage are generated based on the first set of confirmed bits, the second set of confirmed bits and a constant value representative of a voltage shift introduced in the digital-to-analog converter between the first series of comparisons and the second series of comparisons.

Abstract: An amplifier circuit, for a capacitive acoustic transducer defining a sensing capacitor that generates a sensing signal as a function of an acoustic signal, has a first input terminal and a second input terminal, which are coupled to the sensing capacitor and: a dummy capacitor, which has a capacitance corresponding to a capacitance at rest of the sensing capacitor and a first terminal connected to the first input terminal; a first buffer amplifier, which is coupled at input to the second input terminal and defines a first differential output of the circuit; a second buffer amplifier, which is coupled at input to a second terminal of the dummy capacitor and defines a second differential output of the circuit; and a feedback stage, which is coupled between the differential outputs and the first input terminal, for feeding back onto the first input terminal a feedback signal, which has an amplitude that is a function of the sensing signal and is in phase opposition with respect thereto.

Abstract: An apparatus (100) for protecting a circuit (200) from an input volume comprises a switchable element (10) arranged to couple the input voltage (VIN) to the circuit (200) in response to a first control signal (DRV1) having a first value and to decouple the input voltage (VIN) from the circuit (200) in response to the first control signal (DRV1) having a second value. A monitor stage (20) compares a monitored voltage (VMON) to a threshold (VIN). A controller (30) provides the first control signal (DRV1) to the switchable element (10), the first control signal (DRV1) having the first value when the monitored voltage (VMON) is on one side of the threshold (VTH) and the second value when the monitored voltage (VMON) is on the other side of the threshold (VTH), wherein the first value is independent of the input voltage (VIN) and the second value is equal to the input voltage (VIN).

Abstract: A differential output stage of an amplification device, for driving a load, comprises a first and a second differential output stage portion. The first differential output stage portion comprises: a first and a second output circuit; a first driving circuit comprising a first biasing circuit; a second driving circuit comprising a second biasing circuit. The first differential output stage portion comprises: a third output circuit connected between a first node of said first biasing circuit and a first differential output terminal, having a third driving terminal connected to a first driving terminal; a fourth output circuit connected between a first node of the second biasing circuit and the first differential output terminal, having a fourth driving terminal connected to a second driving terminal.

Abstract: A microphone preamplifier circuit is adapted to be connected to a microphone circuit, the microphone circuit including a microphone and at least one output node. The microphone preamplifier circuit includes a preamplifier including: an operational amplifier having at least one input and at least one output; at least one input DC decoupling capacitor connected to the at least one input of the operational amplifier; at least one feedback capacitor connected between the input and the output of the operational amplifier in order to set together with the at least one input DC decoupling capacitor a gain value of the preamplifier circuit; and first and second feed nodes adapted to be fed by first and second bias voltages respectively. The preamplifier further includes at least one switched capacitor adapted to be selectively and alternatively connected in response to a clock signal: between the at least one input and the at least one output of the operational amplifier; and between the first and second feed nodes.

Abstract: A phase shifter, which carries out a ninety-degree phase shift of a sinusoidal input signal having an input frequency, at the same input frequency, envisages: a continuous-time all-pass filter stage, which receives the sinusoidal input signal and generates an output signal phase-shifted by 90° at a phase-shift frequency that is a function of a RC time constant of the all-pass filter stage; and a calibration stage, which is coupled to the all-pass filter stage and generates a calibration signal for the all-pass filter stage, such that the phase-shift frequency is equal to the input frequency of the sinusoidal input signal, irrespective of variations of the value of the input frequency and/or of the RC time constant with respect to a nominal value.

Abstract: An analog input voltage is converted to a digital code by, generating a first set of confirmed bits based on a first series of comparisons of an output of a digital-to-analog converter with the analog input voltage and generating a second set of confirmed bits based on a second series of comparisons of the output of the digital-to-analog converter with the analog input voltage. The first set of confirmed bits is independent of the second series of comparisons. The bits of the digital output code corresponding to the analog input voltage are generated based on the first set of confirmed bits, the second set of confirmed bits and a constant value representative of a voltage shift introduced in the digital-to-analog converter between the first series of comparisons and the second series of comparisons.

Abstract: An amplifier circuit, for a capacitive acoustic transducer defining a sensing capacitor that generates a sensing signal as a function of an acoustic signal, has a first input terminal and a second input terminal, which are coupled to the sensing capacitor and: a dummy capacitor, which has a capacitance corresponding to a capacitance at rest of the sensing capacitor and a first terminal connected to the first input terminal; a first buffer amplifier, which is coupled at input to the second input terminal and defines a first differential output of the circuit; a second buffer amplifier, which is coupled at input to a second terminal of the dummy capacitor and defines a second differential output of the circuit; and a feedback stage, which is coupled between the differential outputs and the first input terminal, for feeding back onto the first input terminal a feedback signal, which has an amplitude that is a function of the sensing signal and is in phase opposition with respect thereto.

Abstract: An analog input voltage is converted to a digital code by, generating a first set of confirmed bits based on a first series of comparisons of an output of a digital-to-analog converter with the analog input voltage and generating a second set of confirmed bits based on a second series of comparisons of the output of the digital-to-analog converter with the analog input voltage. The first set of confirmed bits is independent of the second series of comparisons. The bits of the digital output code corresponding to the analog input voltage are generated based on the first set of confirmed bits, the second set of confirmed bits and a constant value representative of a voltage shift introduced in the digital-to-analog converter between the first series of comparisons and the second series of comparisons.

Abstract: A MEMS acoustic transducer device has a capacitive microelectromechanical sensing structure and a biasing circuit. The biasing circuit includes a voltage-boosting circuit that supplies a boosted voltage on an output terminal, and a high-impedance insulating circuit element set between the output terminal and a terminal of the sensing structure, which defines a first high-impedance node associated with the insulating circuit element. The biasing circuit has: a pre-charge stage that generates a first pre-charge voltage on a first output thereof, as a function of, and distinct from, the boosted voltage; and a first switch element set between the first output and the first high-impedance node. The first switch element is operable for selectively connecting the first high-impedance node to the first output, during a phase of start-up of the biasing circuit, for biasing the first high-impedance node to the first pre-charge voltage.

Abstract: A sensing circuit includes: a follower transistor, having a control terminal; a follower terminal for connection to a load; a bias-current generator, coupled to the follower terminal; and a feedback stage, configured to control the bias-current generator as a function of an input signal on the control terminal of the follower transistor.

Abstract: A MEMS acoustic transducer has: a detection structure, which generates an electrical detection quantity as a function of a detected acoustic signal; and an electronic interface circuit, which is operatively coupled to the detection structure and generates an electrical output quantity as a function of the electrical detection quantity.

Abstract: An electronic USB or similar device 101 with a CMOS audio output stage 105 for driving, in a first mode, e.g., a headset via a port commonly used also in a second mode by a digital data transmission stage 103 for digital data and supply, the audio output stage P-channel transistor MP being switchably back-gate biased by a bias circuit 107 according to the operating mode to achieve high-voltage tolerance.