Abstract: A fully balanced differential difference amplifier includes a first differential input stage that receives an input voltage and a second differential input stage that receives a common-mode voltage. A first resistive-degeneration group is coupled to the first differential input and a second resistive-degeneration group is coupled to the second differential input. A differential output stage generates an output voltage. A first switch is coupled in parallel to the first resistive-degeneration group and a second switch is coupled in parallel with the second resistive-degeneration group. The first and second switches are driven into the closed state when the voltage input assumes a first value such that said first input stage operates in the linear region, and are driven into the open state when the voltage input assumes a second value, higher than the first value, such that the first input stage operates in a non-linear region.

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: A fully balanced differential difference amplifier includes a first differential input stage that receives an input voltage and a second differential input stage that receives a common-mode voltage. A first resistive-degeneration group is coupled to the first differential input and a second resistive-degeneration group is coupled to the second differential input. A differential output stage generates an output voltage. A first switch is coupled in parallel to the first resistive-degeneration group and a second switch is coupled in parallel with the second resistive-degeneration group. The first and second switches are driven into the closed state when the voltage input assumes a first value such that said first input stage operates in the linear region, and are driven into the open state when the voltage input assumes a second value, higher than the first value, such that the first input stage operates in a non-linear region.

Abstract: A FBDDA amplifier comprising: a first differential input stage, which receives an input voltage; a second differential input stage, which receives a common-mode voltage; a first resistive-degeneration group coupled to the first differential input; a second resistive-degeneration group coupled to the second differential input; a differential output stage, generating an output voltage; a first switch coupled in parallel to the first resistive-degeneration group; and a second switch coupled in parallel to the second resistive-degeneration group. The first and second switches are driven into the closed state when the voltage input assumes a first value such that said first input stage operates in the linear region, and are driven into the open state when the voltage input assumes a second value, higher than the first value, such that the first input stage operates in a non-linear region.

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 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: A FBDDA amplifier comprising: a first differential input stage, which receives an input voltage; a second differential input stage, which receives a common-mode voltage; a first resistive-degeneration group coupled to the first differential input; a second resistive-degeneration group coupled to the second differential input; a differential output stage, generating an output voltage; a first switch coupled in parallel to the first resistive-degeneration group; and a second switch coupled in parallel to the second resistive-degeneration group. The first and second switches are driven into the closed state when the voltage input assumes a first value such that said first input stage operates in the linear region, and are driven into the open state when the voltage input assumes a second value, higher than the first value, such that the first input stage operates in a non-linear region.

Abstract: The invention relates to a circuit (100) for use with a loudspeaker (104) having a first differential input terminal (t1) and a second differential input terminal (t2), the circuit (100) comprising: a differential power amplifier (103) having a first differential output terminal (t3) operatively connected to the first differential input terminal (t1) of the loudspeaker (104) and a second differential output terminal (t4) operatively connected to the second differential input terminal (t2) of the loudspeaker (104);—a first resistor (RS1) disposed between the first differential output terminal (t3) of the differential power amplifier (103) and the first differential input terminal (t1) of the loudspeaker (104); a second resistor (RS2) disposed between the second differential output terminal (t4) of the differential power amplifier (103) and the second differential input terminal (t2) of the loudspeaker (104).

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: An integrated circuit for processing audio and voice signals in a telephone is disclosed. The integrated circuit comprises an audio output port having a first and a second output terminal for connection to a first and a second input terminal, respectively, of a speaker. The integrated circuit further comprises an audio input port having a first and a second input terminal for connection to a first and a second output terminal of an audio input source. The integrated circuit also comprises at least one audio output path and one audio input path. Moreover, the integrated circuit comprises a test impedance, such as a resistor, (RT) for measuring an electrical impedance of the speaker.

Abstract: The invention relates to a circuit (100) for use with a loudspeaker (104) having a first differential input terminal (t1) and a second differential input terminal (t2), the circuit (100) comprising: a differential power amplifier (103) having a first differential output terminal (t3) operatively connected to the first differential input terminal (t1) of the loudspeaker (104) and a second differential output terminal (t4) operatively connected to the second differential input terminal (t2) of the loudspeaker (104);—a first resistor (RS1) disposed between the first differential output terminal (t3) of the differential power amplifier (103) and the first differential input terminal (t1) of the loudspeaker (104); a second resistor (RS2) disposed between the second differential output terminal (t4) of the differential power amplifier (103) and the second differential input terminal (t2) of the loudspeaker (104).

Abstract: An integrated circuit for processing audio and voice signals in a telephone is disclosed. The integrated circuit comprises an audio output port having a first and a second output terminal for connection to a first and a second input terminal, respectively, of a speaker. The integrated circuit further comprises an audio input port having a first and a second input terminal for connection to a first and a second output terminal of an audio input source. The integrated circuit also comprises at least one audio output path and one audio input path. Moreover, the integrated circuit comprises a test impedance, such as a resistor, (RT) for measuring an electrical impedance of the speaker.

Abstract: An integrated circuit includes a substrate of semiconductive material, a first circuit environment made from the substrate which includes an output terminal and a first pair of power supply terminals for receiving a first power supply voltage applicable between the terminals. The integrated circuit also includes a second circuit environment made from the semiconductor substrate which includes an input terminal electrically coupled to the output terminal and also includes a second pair of power supply terminals for receiving a second power supply voltage applicable between the second pair of terminals of said second pair. The circuit further includes a device providing protection from electrostatic discharges which includes an integrated resistive device coupled between the input and output terminals.

Abstract: An integrated circuit includes a substrate of semiconductive material, a first circuit environment made from the substrate which includes an output terminal and a first pair of power supply terminals for receiving a first power supply voltage applicable between the terminals. The integrated circuit also includes a second circuit environment made from the semiconductor substrate which includes an input terminal electrically coupled to the output terminal and also includes a second pair of power supply terminals for receiving a second power supply voltage applicable between the second pair of terminals of said second pair. The circuit further includes a device providing protection from electrostatic discharges which includes an integrated resistive device coupled between the input and output terminals.

Abstract: An operational amplifier having a first amplification stage with an input terminal to receive a signal to be amplified, and a first output terminal, and a second amplification stage having a first input terminal connected to the first output terminal, and an output terminal to provide the amplified signal. The first and second amplification stages define, between the input terminal and the output terminal, a signal transfer function having first and second poles. The amplifier further includes a decoupling stage having a further input terminal connected to the first stage input terminal, and a further output terminal connected to the second stage output terminal. The decoupling stage is so arranged as to introduce at least one zero in the operational amplifier transfer function.

Abstract: An integrated circuit includes a substrate of semiconductive material, a first circuit environment made from the substrate which includes an output terminal and a first pair of power supply terminals for receiving a first power supply voltage applicable between the terminals. The integrated circuit also includes a second circuit environment made from the semiconductor substrate which includes an input terminal electrically coupled to the output terminal and also includes a second pair of power supply terminals for receiving a second power supply voltage applicable between the second pair of terminals of said second pair. The circuit further includes a device providing protection from electrostatic discharges which includes an integrated resistive device coupled between the input and output terminals.

Abstract: An operational amplifier having a first amplification stage with an input terminal to receive a signal to be amplified, and a first output terminal, and a second amplification stage having a first input terminal connected to the first output terminal, and an output terminal to provide the amplified signal. The first and second amplification stages define, between the input terminal and the output terminal, a signal transfer function having first and second poles. The amplifier further includes a decoupling stage having a further input terminal connected to the first stage input terminal, and a further output terminal connected to the second stage output terminal. The decoupling stage is so arranged as to introduce at least one zero in the operational amplifier transfer function.

Abstract: An integrated circuit includes a substrate of semiconductive material, a first circuit environment made from the substrate which includes an output terminal and a first pair of power supply terminals for receiving a first power supply voltage applicable between the terminals. The integrated circuit also includes a second circuit environment made from the semiconductor substrate which includes an input terminal electrically coupled to the output terminal and also includes a second pair of power supply terminals for receiving a second power supply voltage applicable between the second pair of terminals of said second pair. The circuit further includes a device providing protection from electrostatic discharges which includes an integrated resistive device coupled between the input and output terminals.

Abstract: A single-ended or differential single-stage, or multi-stage sigma-delta analog-to-digital converter includes at least one switched-capacitor integrator comprising a switched-capacitor network receiving as input a signal to be sampled, and an amplifier coupled in cascade to the switched-capacitor network. A circuit is coupled to the amplifier for feeding an analog dither signal to a virtual ground of the amplifier.

Abstract: A single-loop differential switched-capacitor sigma-delta converter has a three stage double-sampling architecture with reduced current consumption. The converter is stable for large input dynamics, which makes it suitable for RF applications. The three-stage multi-bit double-sampled architecture has a single-loop architecture in which all integrators are included in a same feedback loop. This has been made possible based upon the type of integrators that are connected in cascade. Functioning of the converter is less sensitive to nonlinearities of the operational amplifiers of the integrators.