Abstract: An interface device for connection between two electronic components of an electronic circuit, includes: an input terminal, an output terminal and a reference terminal, an input voltage between the reference and input terminals, an output voltage between the reference and output terminals, an input impedance, and an output voltage gain, at least one resistance connected to at least one terminal among the input and output terminals, at least one analog switch positioned between the output and reference terminals, the switch having a closed or an open state, and control elements for each switch, at least one parameter among the input impedance and the output voltage gain of the device having distinct values as a function of whether the analog switch is closed or open, each analog switch including at least one N-type field effect controllable transistor and one P-type field effect controllable transistor connected in series.

Abstract: An interface device for connection between two electronic components of an electronic circuit, includes: an input terminal, an output terminal and a reference terminal, an input voltage between the reference and input terminals, an output voltage between the reference and output terminals, an input impedance, and an output voltage gain, at least one resistance connected to at least one terminal among the input and output terminals, at least one analog switch positioned between the output and reference terminals, the switch having a closed or an open state, and control elements for each switch, at least one parameter among the input impedance and the output voltage gain of the device having distinct values as a function of whether the analog switch is closed or open, each analog switch including at least one N-type field effect controllable transistor and one P-type field effect controllable transistor connected in series.

Abstract: An ultrasound apparatus for measuring a fluid flow rate includes a processor which receives an analog signal from a receiver transducer then transforms it into a digitized signal used for determining the fluid flow rate. The processor includes a bandpass sigma-delta converter having a bandpass loop filter, and a digital-to-analog converter in a feedback loop.

Abstract: A sigma-delta modulator having a propagation delay &Dgr;t between an input of an analog-to-digital converter and an output of the digital-to-analog converter. A subtractor is located in a direct chain between an amplification unit and the analog-to-direct converter. The output of the amplification unit is connected to a first direct input of the subtractor. An output of the subtractor is connected to the input of the analog-to-digital convertor. The modulator also includes a compensation filter located between the output of the subtractor and a second inverter input of the subtractor. When considering an impulse response of the modulator, at the output of the subtractor, to an impulse sent at the output of the subtractor, including a first part covering a first time interval 0; T with T≧&Dgr;t, and a second part covering a second time interval T; ∝, the compensation filter is designed to contribute to the first part and the amplification unit is designed to contribute only to the second part.