Abstract: High power output may be obtained from a photovoltaic (PV) system by controlling each photovoltaic cell of a solar array individually to operate at its maximum power point. Each cell may have associated power electronics and control circuitry that may be integrated together on a chip which may be advantageously implemented in CMOS, enabling reductions in cost and size. A perturb and observe algorithm may be used to find the maximum power point by measuring the power produced at different operating points, and modifying the operating point in the direction of increased power production. In one aspect, performance of a perturb and observe algorithm may be improved in the presence of noise.

Abstract: Methods and apparatus for a sensor having non-ratiometric fault trip level setting. In embodiments, a sensor has a sensing element with a fixed gain. A signal processing module receives the fault trip level setting and maintains the fault trip level setting constant during changes in the supply voltage.

Abstract: Method and apparatus for a current sensing device including a magnetoresistive magnetic field sensing element positioned with respect to a shaped conductor such that an applied field generated by current through the shaped conductor forms an offset angle theta defined by the applied field and a field of a pinning layer of the magnetoresistive element. The offset angle increases a linearity of the device output for current in the shaped conductor flowing in a first direction.

Abstract: Method and apparatus for a current sensing device including a magnetoresistive magnetic field sensing element positioned with respect to a shaped conductor such that an applied field generated by current through the shaped conductor forms an offset angle theta defined by the applied field and a field of a pinning layer of the magnetoresistive element. The offset angle increases a linearity of the device output for current in the shaped conductor flowing in a first direction. A further sensor can increase linearity in the opposite direction.

Abstract: In one aspect, a magnetic field sensor includes a chopper stabilized amplifier and a plurality of Hall-type elements in parallel and connected to the chopper stabilized amplifier. In another aspect, a magnetic field sensor includes a chopper stabilized amplifier and a plurality of Hall quad elements in parallel and connected to the chopper stabilized amplifier. In a further aspect, a current sensor has a bandwidth of 1 MHz and includes a chopper stabilized amplifier and a plurality of Hall quad elements, fabricated in silicon, in parallel and connected to the chopper stabilized amplifier.

Abstract: A magnetic field sensor for sensing an external magnetic field includes at least one magnetic field sensing element for measuring a magnetic field produced by a first magnetic field generating source and a current generator configured to receive one or more drive current signals at an input thereof and to generate a drive current signal having a periodic waveform and an amplitude offset at an output thereof. Also included is a second magnetic field generating source configured to receive the drive current signal at an input thereof and in response thereto, provide a magnetic field to the at least one magnetic field sensing element. Additionally included is a comparator configured to receive a reference voltage as a first input and an output signal from the at least one magnetic field sensing element as a second input, and in response thereto to generate a comparator output signal having a duty cycle.

Abstract: A system for controlling a motor may include a motor driver circuit for driving a camera motor. A memory capable of storing a plurality of parameters for controlling the camera motor may also be included. A set of parameters from the memory may be chosen to be applied to driving the motor. A motor control module may receive a signal from the control logic module, apply the chosen set of parameters to driving the camera motor, and command the motor driver circuit to drive the motor in accordance with the applied set of parameters. The parameters may be chosen based on desired behavior of the system and various other stimuli.

Abstract: Method and apparatus for a magnetic sensor device having a magnetic field sensing element to generate an output signal and a signal processing module coupled to the magnetic field sensing element, the signal processing module including a linearization module to apply a third order Taylor expansion term to the output signal generated by the magnetic field sensing element. An output module can receive the linearized signal from the linearization module and provide a device output signal.

Abstract: A magnetic field sensor for sensing an external magnetic field includes at least one magnetic field sensing element for measuring a magnetic field produced by a first magnetic field generating source and a current generator configured to receive one or more drive current signals at an input thereof and to generate a drive current signal having a periodic waveform and an amplitude offset at an output thereof. Also included is a second magnetic field generating source configured to receive the drive current signal at an input thereof and in response thereto, provide a magnetic field to the at least one magnetic field sensing element. Additionally included is a comparator configured to receive a reference voltage as a first input and an output signal from the at least one magnetic field sensing element as a second input, and in response thereto to generate a comparator output signal having a duty cycle.

Abstract: The linear position of an object is estimated using multiple magnetic field sensors and a magnet. The multiple magnetic field sensors are held in fixed relation to one another and in moving relation with respect to the magnet. Readings of the first and second magnetic field sensors and the fixed distance between the first and second magnetic field sensors may be used to estimate the linear position. In some embodiments, an estimated frequency of an approximately sinusoidal field versus position characteristic is also used as part of the estimation.

Abstract: The linear position of an object is estimated using multiple magnetic field sensors and a magnet. The multiple magnetic field sensors are held in fixed relation to one another and in moving relation with respect to the magnet. Readings of the first and second magnetic field sensors and the fixed distance between the first and second magnetic field sensors may be used to estimate the linear position. In some embodiments, an estimated frequency of an approximately sinusoidal field versus position characteristic is also used as part of the estimation.

Abstract: A system for controlling a motor may include a motor driver circuit for driving a camera motor. A memory capable of storing a plurality of parameters for controlling the camera motor may also be included. A set of parameters from the memory may be chosen to be applied to driving the motor. A motor control module may receive a signal from the control logic module, apply the chosen set of parameters to driving the camera motor, and command the motor driver circuit to drive the motor in accordance with the applied set of parameters. The parameters may be chosen based on desired behavior of the system and various other stimuli.

Abstract: Methods and apparatus for providing a position sensor to sense the position of a ferromagnetic target and generate a target position signal, a scaling block to receive the target position signal, and a digital RC filter to generate an output using bit shifting for dividing by some factor of two, wherein all division for computations in the RC filter are performed by bit shifts.

Abstract: Methods and apparatus for providing a position sensor to sense the position of a ferromagnetic target and generate a target position signal, a scaling block to receive the target position signal, and a digital RC filter to generate an output using bit shifting for dividing by some factor of two, wherein all division for computations in the RC filter are performed by bit shifts.

Abstract: High power output may be obtained from a photovoltaic (PV) system by controlling each photovoltaic cell of a solar array individually to operate at its maximum power point. Each cell may have associated power electronics and control circuitry that may be integrated together on a chip which may be advantageously implemented in CMOS, enabling reductions in cost and size. A perturb and observe algorithm may be used to find the maximum power point by measuring the power produced at different operating points, and modifying the operating point in the direction of increased power production. In one aspect, performance of a perturb and observe algorithm may be improved in the presence of noise.