Patents Assigned to Melexis Tessenderlo NV
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Publication number: 20120001620Abstract: A magnetic angle sensor comprises a semiconductor chip, at least two magnetic field concentrators of planar shape which are arranged on a surface of the semiconductor chip, and four Hall sensors. Each Hall sensor is assigned to one of the magnetic field concentrators and comprises a Hall element or a cluster of Hall elements. The Hall elements are integrated in the semiconductor chip and are arranged in the region of the edge of the assigned magnetic field concentrator where they are permeated by field lines of the magnetic field which extend approximately perpendicularly to the mentioned surface of the semiconductor chip in the region of the edge of the magnetic field concentrator. Two Hall sensors form a first pair of sensors for measuring a first component of the magnetic field and the two other Hall sensors form a second pair of sensors for measuring a second component of the magnetic field.Type: ApplicationFiled: June 29, 2011Publication date: January 5, 2012Applicant: MELEXIS TESSENDERLO NVInventors: Arnaud Laville, Mathieu Poézart
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Patent number: 8009206Abstract: A system and method adaptively control sensitivity, on a pixel-by-pixel basis, of a digital imager. An illumination intensity level mapping controller determines a number of pixels of image data having illumination intensity levels within a first defined range of illumination intensity levels and determines an illumination intensity level mapping function based upon the determined number of pixels within the first defined range of illumination intensity levels. An exposure controller determines a number of pixels having illumination intensity levels within a second defined range of illumination intensity levels and determines an integration time based upon the determined number of pixels having illumination intensity levels within the second defined range of illumination intensity levels.Type: GrantFiled: January 4, 2002Date of Patent: August 30, 2011Assignee: Melexis Tessenderlo NVInventors: Ichiro Masaki, Lane Gearle Brooks, Vivek A. Sikri, Keith Glen Fife
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Publication number: 20110074327Abstract: In response to the determination or estimation of a back EMF zero crossing event for the phase, a time T1 is calculated, T1 being representative of the desired absolute maximum value of the phase current. Current samples are taken by the current sampling unit symmetrically centred around T1. The values of the samples CS[1] to CS[10] are then input into the error function to calculate an error function value. The calculated error function value is input to the lead angle control unit which calculates a value for lead_angle. The value of lead_angle is calculated to be the adjustment in phase angle of the driving voltage profile that will minimise the absolute value of the error function. In generating and adjusting the driving voltage profile the driving voltage generation unit takes into account both lead_angle and the output of the position and speed estimation unit.Type: ApplicationFiled: September 21, 2010Publication date: March 31, 2011Applicant: Melexis Tessenderlo NVInventors: Christian Paintz, Thomas Freitag
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Patent number: 7872322Abstract: A symmetrical vertical Hall element comprises a well of a first conductivity type that is embedded in a substrate of a second conductivity type and which is contacted by four contacts serving as current and voltage contacts. From the electrical point of view, such a Hall element with four contacts can be regarded as a resistance bridge formed by four resistors R1 to R4 of the Hall element. From the electrical point of view, the Hall element is then regarded as ideal when the four resistors R1 to R4 have the same value. The invention suggests a series of measures in order to electrically balance the resistance bridge. A first measure exists in providing at least one additional resistor. A second measure exists in locally increasing or reducing the electrical conductivity of the well. A third measure exists in providing two Hall elements that are electrically connected in parallel in such a way that their Hall voltages are equidirectional and their offset voltages are largely compensated.Type: GrantFiled: September 10, 2002Date of Patent: January 18, 2011Assignee: Melexis Tessenderlo NVInventors: Christian Schott, Radivoje Popovic, Pierre-Andre Besse, Enrico Schurig
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Patent number: 7859253Abstract: A magnetic structure for detecting a relative motion between the magnetic structure and a magnetic field sensor comprises at least two permanent magnets. The permanent magnets are arranged along a predetermined line which for example is a straight or circular line at a predetermined distance g from each other. The permanent magnets are magnetized in the direction of the line, adjacent permanent magnets having an opposite direction of magnetization.Type: GrantFiled: June 26, 2008Date of Patent: December 28, 2010Assignee: Melexis Tessenderlo NVInventors: Angelo Manco, Robert Racz, Michael Triulzi
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Publication number: 20100213968Abstract: A test insert for an integrated circuit according to the present invention comprises access contacts and an electrical path. Furthermore, there may be additional access contacts and a plurality of different electrical paths. The electrical path is comprised of a plurality of tracks, each track provided at a single layer of the integrated circuit and connected to the other tracks by interconnecting vias. The vias provide interlayer contacts and thus allow the tracks to be connected into a single electrical track. In one embodiment, an access contact is connected to ground; another contact is connected to a reference voltage; and connected to various points in the electrical path are transistor-resistor pairs. The transistor-resistor pairs are in connected between earth and a third access contact. If the electrical path is intact at the track connected to a transistor-resistor pair, a current can flow between contact and the respective earth of the transistor-resistor pair.Type: ApplicationFiled: February 25, 2010Publication date: August 26, 2010Applicants: MELEXIS TESSENDERLO NV, MELEXIS UK Ltd.Inventors: Rudi De Winter, William Robert Betts
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Patent number: 7760938Abstract: A method and apparatus for enhancing the contrast of an image. The method may include creating a histogram of an original image, determining output pixel values based on one or more thresholds that define a minimum number of pixels in each histogram bin, and correcting the original image using the output pixel values.Type: GrantFiled: October 11, 2005Date of Patent: July 20, 2010Assignee: Melexis Tessenderlo NVInventors: Vivek Ashwini Sikri, Xiaofeng Michael Lu
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Publication number: 20100141192Abstract: The present invention there is provides a method of determining the rotor position in an electric motor comprising the steps of: superimposing one or more alternating signals on to the driving waveform so as to generate one or more oscillating currents in the stator coils; monitoring the variation in magnitude of the oscillating currents and thereby determining the rotor position. Typically, two alternating signals are applied in opposition so as to have no net effect on the torque applied by the driving waveform. Using this technique rotor position estimation can be obtained at start-up from stand-still and at low to medium speeds. The method can be used in applications where a fast motor start is needed under unknown load conditions and can be used to detect when the rotor has passed a certain position that coincides with the commutation instance.Type: ApplicationFiled: December 10, 2009Publication date: June 10, 2010Applicant: MELEXIS TESSENDERLO NVInventors: Christian Paintz, Thomas Freitag
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Patent number: 7719583Abstract: A method and apparatus to selectably operate a pixel circuit within an active pixel image sensor in a source follower mode or a common source amplifier mode.Type: GrantFiled: September 7, 2005Date of Patent: May 18, 2010Assignee: Melexis Tessenderlo NVInventors: Hae-Seung Lee, Keith G. Fife
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Patent number: 7697050Abstract: A method and apparatus to perform low noise reset of a pixel circuit within an active pixel image sensor.Type: GrantFiled: September 7, 2005Date of Patent: April 13, 2010Assignee: Melexis Tessenderlo NVInventors: Hae-Seung Lee, Keith G. Fife
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Patent number: 7612595Abstract: A circuit for generating non-overlapping clock signals includes a programmable delayed reference clock signals circuit to produce a plurality of delayed reference clock signals and a plurality of delay clock signal generators, operatively connected to the programmable delayed reference clock signals circuit, to generate non-overlapping clock signals. Each delay clock signal generator includes a latch or flip-flop to control a delay in a rising edge of a clock signal and to output a first signal, another latch or flip-flop to control a delay in a falling edge of a delayed clock signal and to output a first signal, and a logic circuit to generate the clock signal from the first and second signals. The latches or flip-flops independently control a delay in the rising edge of the clock signal in response to one of the plurality of delayed reference clock signals.Type: GrantFiled: September 17, 2007Date of Patent: November 3, 2009Assignee: Melexis Tessenderlo NVInventors: Jungwook Yang, Lane Brooks, Pavan Mudunuru
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Patent number: 7609303Abstract: A method and apparatus to perform low noise reset of a pixel circuit within an active pixel image sensor.Type: GrantFiled: October 12, 2005Date of Patent: October 27, 2009Assignee: Melexis Tessenderlo NVInventors: Hae-Seung Lee, Keith G. Fife
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Patent number: 7557334Abstract: A method and apparatus to operate a pixel circuit within an active pixel image sensor in a common gate amplifier mode.Type: GrantFiled: January 31, 2008Date of Patent: July 7, 2009Assignee: Melexis Tessenderlo NVInventors: Hae-Seung Lee, Keith G. Fife