Stmicroelectronics S.r.l.

Stmicroelectronics Asia Pacific Pte Limited

Stmicroelectronics International N.v.

Paolo Angelini

Roberto Pio Baorda

Danilo Karim Kaddouri

Yannick Guedon

Kien Beng Tan

Ernesto Lasalandra

Dianbo Guo

Tommaso Ungaretti

Giovanni Carlo Tripoli

Francesco Borgioli

Carlo Valzasina

Luciano Prandi

Stefano Ramorini

Carlo Caminada

Dario Paci

Francesco Procopio

Sze-Kwang Tan

Andrea Visconti

Francesco Diazzi

Ming Zhu

Marco Garbarino

Lorenzo Ercolini

A read circuit for capacitive sensors such as a MEMS microphones includes a sensor node configured to be coupled to a capacitive sensor to apply a bias voltage to the sensor and sense the capacitance value of the sensor wherein the voltage at the sensor node is indicative of the capacitance value of the capacitive sensor. A switch is provided between the sensor node and the intermediate node. A shock detector coupled to the sensor node and the switch asserts a shock signal to make the switch conductive in response to a shock applied to the capacitive sensor, and de-asserts the shock signal to make the switch non-conductive with a delay after the end of the shock applied to the capacitive sensor.

Read circuit for capacitive sensors, corresponding sensor device and method

Disclosed herein is a system for measuring current, including an input inductor and a self-test inductor through which respective input and self-test currents flow. A Hall-effect sensor circuit senses magnetic fields around these inductors, producing differential voltage outputs. These outputs are received by an input and self-test extraction circuit, which alternatingly outputs differential voltages representative of the magnetic fields around the inductors. Amplification of these differential voltages is performed by an amplifier. Sampling of the amplified differential voltages is performed by two sample/hold circuits, each designated for a specific inductor's magnetic field. An integrator circuit adjusts a voltage for the Hall effect sensor circuit, causing the gain applied to the sampled differential voltage to remain consistent and uninfluenced by the sensitivity of the Hall effect sensor circuit.

Closed loop, high accuracy hall effect sensor AFE with autozeroed switched-capacitor analog accumulator

In accordance with an embodiment, a method of measuring a load current flowing through a current measurement resistor coupled between a source node and a load node includes: measuring a first voltage across a replica resistor when a first end of the replica resistor is coupled to the source node and a second end of the replica resistor is coupled to a reference current source; measuring a second voltage across the replica resistor when the second end of the replica resistor is coupled to the source node and the first end of the replica resistor is coupled to the reference current source; measure a third voltage across the current sensing resistor; and calculating a corrected current measurement of the load current based on the measured first voltage, the measured second voltage and the measured third voltage.

Current sensing circuit

A current measurement circuit, for wireless charging systems, for instance, comprises a differential input configured to have applied an input voltage sensed across a shunt resistor traversed by a current to be measured, a voltage reversal switch arrangement selectively switchable to reverse the polarity of the input voltage as applied between a first and a second voltage sensing nodes as well as a first and a second current flow line between the voltage sensing nodes and ground. A difference resistor intermediate the two current flow lines is traversed by a current which is a function of the input voltage as applied to the first and second sensing nodes via the voltage reversal switch arrangement. First and second current sensing nodes at the two current flow lines are coupled to a differential current output via a current reversal switch arrangement selectively switchable to reverse the output current polarity.

Sensing circuit, corresponding device and method

Hall sensing signals are received in a spinning readout pattern of subsequent readout phases, wherein the pattern is cyclically repeated at a spinning frequency and a polarity of the Hall sensor signals is reversed in two non-adjacent readout phases of the readout pattern. A signal storage circuit includes signal storage capacitors. An accumulation circuit includes accumulation capacitors. A switch network is selectively actuated to couple the signal storage capacitors with the accumulation capacitors synchronously with phases in the spinning readout pattern in subsequent alternating first and second periods. The spinning output is stored with alternating opposite signs on the signal storage capacitors and the Hall sensing signals are stored in the signal storage capacitors and then accumulated on the accumulation capacitors with alternate signs in subsequent periods. The accumulated output signal is then demodulated with a demodulation frequency half the spinning frequency.

Hall sensor readout circuit, corresponding device and method

An embodiment voltage-current converter circuit comprises a first amplifier and a second amplifier having homologous first input nodes configured to receive a voltage signal therebetween as well as homologous second input nodes having a resistor coupled therebetween. First and second current mirror circuits are provided comprising first input transistors having their control terminal coupled to the output nodes of the amplifiers. First and second current sensing circuitry having first and second current output nodes are coupled to the current mirror output nodes of the current mirror circuits and configured to provide therebetween a current which is a function of the voltage signal between the homologous first input nodes of the amplifier.

Voltage-current converter, corresponding device and method

A sensor comprises a first transistor comprising a first control terminal, a second transistor that is a scaled version of and connected to the first transistor and comprising a second control terminal, an operational amplifier connected to both the first and second transistors and configured to generate an intermediate signal at an output terminal, a variable current source, a current mirror, a measurement circuit, and a chopper circuit. The first and second control terminals are configured to receive a drive signal. The variable current source is configured to generate a first variable current as a function of the intermediate signal. The current mirror configured to apply a second variable current proportional to the first variable current to the second transistor. The measurement circuit is configured to generate a measurement signal indicative of current through the first transistor. The chopper circuit is configured to shift an offset of the operation amplifier.

Current sensing system comprising a scaled transistor and methods of operation thereof

A compensation circuit receives a sensing signal from a Hall sensor and outputs a compensated Hall sensing signal. The compensation circuit has a gain that is inversely proportional to Hall sensor drift mobility. The compensated Hall sensing signal is temperature-compensated.

Temperature compensation circuit, corresponding device and method

A Hall sensor compensation circuit includes an input node configured for receiving a bias signal for a Hall sensor. A bias node provides to the Hall sensor a compensated bias signal. A compensation network coupled between the input node and the bias node has a gain inversely proportional to Hall mobility, &#x3bc;', wherein the Hall sensing signal is temperature-compensated.

An integrated sensor device including a first die, housing a sensor element to detect a quantity external to the sensor device and transduce the external quantity into an electrical sensing signal; a second die mechanically coupled to the first die so that the first and second dies are stacked on one another along one and the same axis; and at least one heater of a resistive type integrated in the first die and/or in the second die, having a first conduction terminal and a second conduction terminal configured to couple respective first and second conduction terminals of a signal generator for causing an electric current to flow, in use, between the first and second conduction terminals of the heater and generate heat by the Joule effect. It is possible to carry out calibration in temperature of the sensor element.

Sensor device with integrated calibration system and calibration method

A differential current conveyor circuit includes two or more single-ended current conveyor stages and a common bias stage. First and second switches are set between the control terminals of the transistors in the common bias stage and a respective one of a first and a second coupling line of the single ended stages can be switched between the following: a reset state of the circuit with the transistors in the common bias stage coupled to the first and second coupling lines with the single-ended stages set to a bias condition; and a sensing state of the circuit with the transistors in the common bias stage decoupled from the first and second coupling lines, with the single-ended stages in a high impedance state with the control terminals of the input transistors of the single ended stages capacitively coupled to the input terminal.

Differential current conveyor circuit, corresponding device, and method of operation thereof

A sensor includes a first transistor including a first terminal and a second terminal defining a current path, and a first gate terminal configured to receive a drive signal. The sensor further includes a sensor circuit configured to generate a measurement signal indicative of a first current flowing through the first transistor. The sensor circuit includes a second transistor including a third terminal, a fourth terminal, and a second gate terminal. The third terminal is connected to the first terminal of the first transistor. The second gate terminal is configured to receive the drive signal. The second transistor is a scaled version of the first transistor. The sensor circuit further includes an operational amplifier, a variable current source, a current mirror, and a measurement circuit.

A circuit includes a first transistor having a control terminal and a current path between first and second current path terminals. A second transistor has a control terminal and a current path between first and second current path terminals. The first current path terminal of the first transistor is coupled to the first current path terminal of the second transistor at an intermediate point. A first current buffer has an input and an output. The input of the first current buffer is coupled to the second current path terminal of the first transistor. A second current buffer has an input and an output, the input of the second current buffer being coupled to the second current path terminal of the second transistor. A summation node is coupled to the outputs of the first and second current buffer.

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Bologna, Italy

Paolo Angelini