Abstract: Motor control circuits and associated methods to control an electric motor provide a plurality of drive signal channels at the same phase, resulting in reduced jitter in the rotational speed of the electric motor.

Abstract: An electronic circuit has a differential amplifier with a differential transistor pair having two transistors. The electronic circuit also has two digital-to-analog converters, a respective one of the two digital-to-analog converters coupled to each respective one of the two transistors. Control bits adjust the DACs to provide an offset voltage adjustment of the differential amplifier.

Abstract: A magnetic field sensor includes a true power on state (TPOS) detector for which a measured threshold value is stored prior to power down and recalled upon power up. A corresponding method is associated with the magnetic field sensor.

Abstract: In one aspect, a current driver, includes an operational amplifier that includes a first input port configured to receive a reference signal and a second input port configured to receive a variable signal. The variable signal is a function of an output current of the current driver. The reference signal corresponds to a selected maximum output current of the current driver. The current driver also includes a feedback transistor comprising a gate coupled to the output of the operational amplifier and a summing junction coupled to a drain of the feedback transistor and configured to receive a signal from the drain to enable clamping of the output current of the current driver to the maximum output current when the variable signal exceeds the reference signal. The summing junction is coupled to a set of transistors configured to provide the output current of the current driver.

Abstract: A Hall effect transducer in a semiconductor wafer comprises a first layer of semiconducting material, a second layer of semiconducting material, and a contact structure configured to provide a path for electrical current to pass through the second layer. The second layer has higher electron hole mobility than the first layer, and is epitaxially grown atop the first layer.

Abstract: An electronic circuit and an associated method used to drive an electric motor provide a user selectable relationship between rotational speed of the electric motor and phase advances of signals used to drive the electric motor. By selecting the relationship, efficiency of the electric motor drive can be improved.

Abstract: 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.

Abstract: A magnetic field sensor and a method used therein provide an output signal in angle units representative of an angle of rotation of a target of and also an output signal in speed units representative of a speed of rotation of the target object. A power control circuit can cycle a magnetic field sensor on and off in accordance with a sensed rotation speed of the object.

Abstract: A circuit to detect a movement of an object includes a magnetic field sensing element for generating a magnetic field signal proportional to a magnetic field associated with the object and a motion detector to generate a motion signal indicative of the movement of the object. The motion detector includes a peak identifying circuit to provide a peak signal and a peak sample selection module that selects a sample associated with one or more prior cycles of a magnetic field signal to generate a selected peak signal. The motion detector further includes a threshold generator to generate a threshold signal as a function of the selected peak signal and a comparator to compare the threshold signal with the magnetic field signal to generate the motion signal. Peak samples from prior magnetic field signal cycles may be averaged for use to establish the threshold signal. A method associated with the circuit is also described.

Abstract: Electronic circuits provide an error signal to control a regulated output voltage signal generated by a controllable DC-DC converter for driving one or more series connected strings of light emitting diodes.

Abstract: A linear motion control device for use in a linear control system is presented. The linear motion control device includes a coil driver to drive a coil that, when driven, effects a linear movement by a motion device having a magnet. The linear motion control device also includes a magnetic field sensor to detect a magnetic field associated with the linear movement and an interface to connect an output of the magnetic field sensor and an input of the coil driver to an external controller. The interface includes a feedback loop to relate the magnetic field sensor output signal to the coil driver input.

Abstract: A magnetic field sensor includes a diagnostic circuit that allows a self-test of most of, or all of, the circuitry of the magnetic field sensor, including a self-test of a magnetic field sensing element used within the magnetic field sensor. The magnetic field sensor can generate a diagnostic magnetic field to which the magnetic field sensor is responsive.

Abstract: In one aspect, a circuit includes a switching regulator configured to provide power to a load, a current regulator circuit coupled to the load and a response circuit configured to provide a control signal to the switching regulator in response to electrical changes of the current regulator circuit. The control signal changes non-linearly with respect to the electrical changes at the current regulator circuit. In another aspect, a circuit includes an adaptive regulation voltage circuit configured to provide a regulation voltage to a first input of an amplifier to maintain operability of a current regulator circuit. The adaptive regulation voltage circuit replicates electrical characteristics of the current regulator circuit.

Abstract: A motion sensor has an output protocol processor configured to provide a validated output signal after a determined time period, wherein the determined time period is extended if a vibration is detected.

Abstract: An apparatus and a method provide an output signal indicative of a speed of rotation and a direction of rotation of a ferromagnetic object capable of rotating. A variety of signal formats of the output signal are described.

Abstract: Methods and apparatus to provide an integrated circuit package having a conductive leadframe, a non-conductive die paddle mechanically coupled to the leadframe, and a die disposed on the die paddle and electrically connected to the leadframe. With this arrangement, eddy currents are reduced near the magnetic field transducer to reduce interference with magnetic fields.

Abstract: An apparatus and a method provide an output signal indicative of a speed of rotation and a direction of rotation of a ferromagnetic object capable of rotating. A variety of signal formats of the output signal are described.

Abstract: A motion sensor includes an amplitude difference processor coupled to receive a first signal representative of a first one of a plurality of AGC control signals and a second signal representative of a second one of the plurality of AGC control signals. The amplitude difference processor is configured to detect if a value of the first signal is representative of a different gain than a value of the second signal by a predetermined amount. In response to the detection, the AGC processor is configured to change the value of the first one of the plurality of AGC control signals to bring its value closer to the value of the second one of the AGC control signals. A method and computer-readable storage medium can use the motion sensor.

Abstract: A magnetic field sensor includes a reference-field-sensing circuit channel that allows a calibration or a self-test of the circuitry of the magnetic field sensor. The magnetic field sensor can generate a reference magnetic field to which the magnetic field sensor is responsive.

Abstract: 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.