摘要:
A magnetic field sensor uses an angle sensor to measure and angle of rotation of a target object to which a magnet is attached. The angle sensor in combination with electronics can generate an angle sensor output signal related to a direction of a magnetic field of the magnet. The angle sensor output signal can be compared to thresholds to generate a magnetic field sensor output signal the same as a known true power on state (TPOS) sensor output signal. A corresponding method is also described.
摘要:
A magnetic field sensor has a plurality of vertical Hall elements arranged in at least a portion of a polygonal shape. The magnetic field sensor includes an electronic circuit to process signals generated by the plurality of vertical Hall elements to identify a direction of a magnetic field. A corresponding method of fabricating the magnetic field sensor is also described.
摘要:
Presented herein is a magnetic field sensor architecture that uses outputs of a peak detector and threshold detector operating in parallel to detect magnetic anomalies that may be associated with the target being sensed, e.g., a rotational ferromagnetic object such as a toothed gear, and use such detection to prevent sensor malfunction. The sensor includes an edge detection circuit and an error detection circuit. In one embodiment, the edge detection circuit includes circuits to detect edges (or transitions) of the threshold and peak detector output signals and the error detection circuit includes circuits, responsive to the edge detection circuit, to indicate an error when a “missed transition” occurs or a peak-to-peak value of an input signal as detected by the peak detector for a current cycle differs from an expected peak-to-peak value by a predetermined amount.
摘要:
A sensor with multiple magnetic field sensing elements for use in current sensing and other applications is presented. In one configuration, the sensor can obtain differential and absolute current measurements of current in current-carrying conductors. When employed in a ground fault interrupter (GFI) application, a first magnetic field sensing element can be used to measure the absolute current flowing in the phase conductor (phase current), a second magnetic field sensing element can be used to measure the absolute current flowing in the neutral conductor (neutral current) and a difference between the phase and neutral currents can be measured by a third magnetic field sensing element or determined from measurements of the first and second magnetic field sensing elements. In another configuration, the sensor can obtain a measure of the difference between currents and/or the sum of currents in current-carrying conductors.
摘要:
A differential magnetic field sensor that enables operation that is independent of sensor-to-target orientation is presented. The differential magnetic field sensor is provided with at least two differential channels. Each differential channel includes a pair of magnetic field sensing elements and has a respective sensing axis defined by those magnetic field sensing elements. The sensing axes are not aligned with respect to each other. One sensing axis is positioned relative to a reference axis of a target profile to define an orientation angle between the sensing axis and the reference axis. The differential magnetic field sensor includes circuitry to produce differential signals associated with the differential channels and use those differential signals to produce a single differential signal having an amplitude that is independent of the orientation angle.
摘要:
An integrated circuit includes a sensor for providing a sensor output signal and a diagnostic circuit coupled to the sensor for providing a self-diagnostic signal. The self-diagnostic signal comprises the sensor output signal during a first time duration and an inverted sensor output signal during a second different time duration.
摘要:
A magnetic field sensor has a plurality of vertical Hall elements arranged in at least a portion of a polygonal shape. The magnetic field sensor includes an electronic circuit to process signals generated by the plurality of vertical Hall elements to identify a direction of a magnetic field. A corresponding method of fabricating the magnetic field sensor is also described.
摘要:
A circuit to detect a movement of an object provides a threshold selection module that uses one or more threshold signals identified prior to a present cycle of magnetic field signal in order to establish a threshold signal used for a present cycle of the magnetic field signal. A method associated with the circuit is also described.
摘要:
A circuit to detect a movement of an object provides a threshold selection module that uses one or more threshold signals identified prior to a present cycle of magnetic field signal in order to establish a threshold signal used for a present cycle of the magnetic field signal. A method associated with the circuit is also described.
摘要:
A magnetic field sensor includes a lead frame, a semiconductor die supporting a magnetic field sensing element, a non-conductive mold material enclosing the die and a portion of the lead frame, a ferromagnetic mold material secured to the non-conductive mold material and a securing mechanism to securely engage the mold materials. The ferromagnetic mold material may comprise a soft ferromagnetic material to form a concentrator or a hard ferromagnetic material to form a bias magnet. The ferromagnetic mold material may be tapered and includes a non-contiguous central region, as may be an aperture or may contain the non-conductive mold material or an overmold material. Further embodiments include die up, lead on chip, and flip-chip arrangements, wafer level techniques to form the concentrator or bias magnet, integrated components, such as capacitors, on the lead frame, and a bias magnet with one or more channels to facilitate overmolding.