Abstract: A linear regulator includes a drive circuit having an input and an output, with the output configured to drive a control terminal of a power transistor for the delivery of a load current. An error amplifier functions to amplify a difference between a reference signal and a feedback signal to generate an error signal at the input of the drive circuit. A compensation circuit includes a series circuit formed by a compensation capacitor and a variable resistance circuit, where the series circuit is coupled to the input of the drive circuit. A current sensing circuit operates to sense the load current. The resistance of the variable resistance circuit is varied in response to the sensed load current.

Abstract: A method and apparatus for determining the attitude of an object is provided herein. The method for determining the attitude of the object comprises: receiving a gravity acceleration signal and a geomagnetic field signal, the gravity acceleration signal and the geomagnetic field signal changing with the attitude of the object accordingly; determining a gravity field representation in an object coordinate system according to the gravity acceleration signal, and determining a geomagnetic field representation in the object coordinate system according to the geomagnetic field signal; calculating a conversion parameter of coordinate system between to the object coordinate system and a terrestrial coordinate system according to the gravity field representation and the geomagnetic field representation in the object coordinate system; and determining the attitude of the object according to the conversion parameter of coordinate system.

Abstract: A switching regulator includes circuitry for reducing conductive emissions caused when the regulators switch from one transistor switch to the other. The switching regulator includes at least one switch with a diode connected from the source to the drain of at least one of the transistor switches. When the regulator switches from one transistor switch to the other, the circuitry initiates turning on the switch with a relatively small, current-limited signal, waits for the diode across the recently turned off switch to complete reverse recovery, and then quickly turns the new switch fully on.

Abstract: An oscillator circuit operates to selectively charge and discharge a capacitance with a charging circuit. An inverting circuit includes a first transistor, second transistor, third transistor and fourth transistor having source-drain paths coupled in series. The second and third transistors are connected as an inverter with an input coupled to the capacitance and an output. A feedback loop couples the output of the inverter to an input of the charging circuit. A first shunting transistor is configured to selective shunt across the first transistor in response to a first logic state of a feedback signal in the feedback path. A second shunting transistor is configured to selective shunt across the fourth transistor in response to a second logic state of the feedback signal in the feedback path.

Abstract: A voltage regulator includes two input pairs of opposite type transistors, p-type and n-type, to provide a soft-start functionality for gradually increasing the voltage regulator's output voltage from zero, or a voltage below the thresholds of the n-type transistors, to an operational voltage. The voltage regulator operates in a soft-start mode during which a variable input voltage signal is ramped up to allow the output voltage to reach the operational voltage, and a normal-operation mode during which the operational voltage is maintained.

Abstract: Congruent power and timing signals in a single electronic device. In an embodiment, a circuit may include just one isolation transformer operable to generate a power signal and a timing signal. On the secondary side, two branches may extract both a power signal and a clock signal for use in the circuit on the isolated secondary side. The first branch may be coupled to the transformer and operable to manipulate the signal into a power signal, such as a 5V DC signal. Likewise, the second circuit branch is operable to manipulate the signal into a clock signal, such as a 5 V signal with a frequency of 1 MHz. By extracting both a power supply signal and a clock signal from the same isolation transformer on the secondary side, valuable space may be saved on an integrated circuit device with only having a single winding for a single isolation transformer.

Abstract: A current detection module generates a first current detection signal of a first current flowing through a first power line and a second current detection signal of a second current flowing through a second power line. A multiplexer periodically switches between the two current detection signals in response to a control signal so as to output the first current detection signal within a first duration of each cycle of the control signal and the second current detection signal within a second duration of each cycle of the control signal. A signal processing module generates an energy accumulation signal according to the output of the multiplexer and a voltage detection signal of the voltage of a phase line. A control module provides the control signal to the multiplexer, and generates an effective value of the second current during the second duration.

Abstract: Apparatus and methods to compensate hard iron and soft iron magnetic interference in magnetic sensing devices are described. Hard and soft iron interference may be modeled using an ellipsoidal surface generated by a plurality of magnetic field measurements. A displacement of the ellipsoid from a reference frame origin corresponds to hard iron or permanent magnetic field interference. A shape and orientation of the ellipsoid corresponds to soft iron magnetic field interference. The ellipsoidal surface may be analyzed to obtain magnetic field compensation values for cancelling hard iron and soft iron interference.

Abstract: A magnetic sensor is calibrated by acquiring magnetic field measurements, fitting at least part of the plurality of magnetic field measurements to an ellipsoid model to obtain a coordinate of a center of the ellipsoid model, and determining a calibration offset according to the coordinate of the center of the ellipsoid model. The calibration offset is used to calibrate the magnetic sensor. The magnetic sensor itself obtains the magnetic field measurements. A processing device coupled to the magnetic sensor operates to process the magnetic field measurements is accordance with the ellipsoid mode and determine the calibration offset.

Abstract: The invention relates to a method of determining a zero-bias error of a gyroscope, an apparatus for determining a zero-bias error of a gyroscope and a system including the apparatus. The method includes the steps of: a. obtaining a set of outputs of the gyroscope; b. determining a dispersion degree of the outputs; c. determining whether the dispersion degree satisfies a predetermined condition and performing the step of d or e based upon a result of the determination; and d. determining an average of the outputs as the zero-bias error of the gyroscope when the dispersion degree satisfies the predetermined condition; or e. obtaining another set of outputs of the gyroscope and repeating performing the steps of b to c on the another set of outputs when the dispersion degree does not satisfy the predetermined condition.

Abstract: A method and apparatus for determining the attitude of an object is provided herein. The method for determining the attitude of the object comprises: receiving a gravity acceleration signal and a geomagnetic field signal, the gravity acceleration signal and the geomagnetic field signal changing with the attitude of the object accordingly; determining a gravity field representation in an object coordinate system according to the gravity acceleration signal, and determining a geomagnetic field representation in the object coordinate system according to the geomagnetic field signal; calculating a conversion parameter of coordinate system between to the object coordinate system and a terrestrial coordinate system according to the gravity field representation and the geomagnetic field representation in the object coordinate system; and determining the attitude of the object according to the conversion parameter of coordinate system.