A method for synchronizing an internal combustion engine includes: a) a first step of acquiring, by the camshaft sensor, signals corresponding to at least five cam edges x; b) a second step of determining the value, from the camshaft signal, of a first, second and third actual ratio; c) a third step of establishing, for each actual value ratio obtained in b), a list of possible cam edges x by comparing the values of the first, second and third actual ratios, respectively, with a tolerance window corresponding to a value of a first, second or third theoretical ratio for a given cam edge x, each weighted by a tolerance factor k; and d) a fourth step of determining the cam edge x seen by the camshaft sensor, the cam edge actually seen by the sensor corresponding to the cam edge x common to the three lists established in c).

A method for automatic calibration of a camshaft sensor for a motor vehicle engine. The sensor includes a processing module configured to generate, from a raw signal indicative of the variations in a magnetic field which are caused by a rotation of a target and measured by a primary cell, an output signal indicative of the moments at which teeth of the target pass past the primary cell. The sensor further includes two secondary measurement cells. The calibration method therefore makes it possible to determine two different switching thresholds for each tooth from a differential signal indicative of a difference in magnetic field measurement by the secondary cells. Also disclosed are a camshaft sensor implementing such a method, and a motor vehicle including such a sensor.

A method for calibrating a position measurement system includes receiving measurement data from the position measurement system and determining that the measurement data includes periodic distortion data. The position measurement system includes a nonius track and a master track. The method also includes modifying the measurement data by decomposing the periodic distortion data into periodic components and removing the periodic components from the measurement data.

A rotational angle detection device includes a magnet with n pole pairs (where n≥3) provided to be integrally rotatable with a rotating body; magnetic detection parts including first and second magnetic detection parts; a corrected signal generation part generating first and second corrected signals; and a rotational angle detection part detecting the rotational angle of the rotating body based on the first and second corrected signals. The waveform of the first and second detection signals have a phase difference of 90° from each other. The corrected signal generation part adds the first sensor signals and adds the second sensor signals. The region at the perimeter of the magnet includes first through nth regions, and at least two of the first and second magnetic sensor parts are positioned in different regions from each other among the first through nth regions.

A two-wire reference accelerometer includes integrated mechanical transducing and self-calibration capability based on gravity only. The reference accelerometer includes an external two-wire connector and an internal three-wire transducer that responds to both steady-state acceleration and time-varying accelerations by producing a modulated transducer output signal having a steady-state waveform when the transducer senses steady state acceleration and a time-varying waveform when the transducer senses time-varying accelerations. A signal conditioning circuit conditions the transducer output signal and applies it to the two-wire electrical connector as a modulated reference accelerometer output signal. The transducer and the signal conditioning circuit can operate without modification in either a DUT calibration mode or a self-calibration mode. The self-calibration mode determines the 1 g output sensitivity of the reference accelerometer from first and second readings of the reference accelerometer output signal taken while the reference accelerometer rests on a non-accelerating surface in respective non-inverted and inverted orientations.

In some embodiments, a method can include receiving, by an angle sensor, a first periodic angle signal indicative of an angle of a first magnetic field associated with a first track of a target; receiving, by the angle sensor, a second periodic angle signal indicative of an angle of a second magnetic field associated with a second track of the target; generating an uncorrected absolute angle signal indicative of an absolute angle of the target based on the first and second periodic angle signals; determining an estimated error associated with the uncorrected absolute angle signal based on the first periodic angle signal and the second periodic signal; subtracting the estimated error from the uncorrected absolute angle to generate a corrected absolute angle signal; and providing the corrected absolute angle signal as output of the angle sensor.

There is provided a light control circuit including a light detector, a frequency detector, an error amplifier, an NMOS driver and a light source. The frequency detector identifies a signal frequency according to detected voltage signals outputted by the light detector and generates a control signal accordingly. The NMOS driver changes a drive current of the light source according to an output of the error amplifier. The error amplifier changes a bandwidth thereof according to the control signal from the frequency detector to regulate a response time of the drive current of the light source.

An angle sensor includes a plurality of magnetic sensors and a processor. The plurality of magnetic sensors generate a plurality of detection values representing directions of a composite magnetic field, which is a composite of a magnetic field to be detected and a noise magnetic field. The processor assumes a group of estimated unknowns. The group of estimated unknowns is a set of estimated values of a first, a second, and a third unknown. The first unknown corresponds to an angle detection value. The second unknown corresponds to the direction of the noise magnetic field. The third unknown corresponds to the strength of the noise magnetic field. The processor executes a process for determining the group of estimated unknowns a plurality of times, and assumes an estimated value of the first unknown in the last determined group of estimated unknowns as the angle detection value.

A method for determining the angle of the rotor of an electric motor includes receiving a first rotor position signal from a rotor position sensor by using a control unit, the first rotor position signal including a plurality of orders; determining the angular velocity of the electric motor at least by way of the first rotor position signal by using an angular velocity module of the control unit; determining a first base signal by way of the determined angular velocity and the first rotor position signal by using a first filter module of the control unit; and determining the angle of the rotor at least by way of the determined first base signal by using an angle module of the control unit.

A rotary movement position sensor is presented that includes a first sensor output, a second sensor output, a first signal processing unit, a second signal processing unit, a first system output providing the output of the first signal processing unit or of the second signal processing unit, and a second system output providing the output of the second signal processing unit or of the first signal processing unit. A swapping unit that swaps the first signal processing unit between the first sensor output and first system output to the second sensor output and second system output and simultaneously swaps the second signal processing unit from the second sensor output and second system output to the first sensor output and first system output and vice versa. A method for detecting errors in a position sensor system is also presented.