An apparatus for driving LEDs using high voltage includes two LED driving circuits and two switches that can be turned on or off by a universal controller so as to connect the two LED driving circuits in two different configurations. When the input voltage is in a range from rectified 90 volt AC to rectified 140 volt AC, the two switches are controlled in such a way that the two LED driving circuits are connected in parallel. When the input voltage V.sub.IN is in a range from rectified 180 volt AC to rectified 265 volt AC, the two switches are controlled to connect the LED segments of the LED unit in one LED driving circuit in series with the other LED driving circuit.

An apparatus for driving LEDs using high voltage includes two LED driving circuits and two switches that can be turned on or off by a universal controller so as to connect the two LED driving circuits in two different configurations. When the input voltage is in a range from rectified 90 volt AC to rectified 140 volt AC, the two switches are controlled in such a way that the two LED driving circuits are connected in parallel. When the input voltage V.sub.IN is in a range from rectified 180 volt AC to rectified 265 volt AC, the two switches are controlled to connect the LED segments of the LED unit in one LED driving circuit in series with the other LED driving circuit.

Provided are an apparatus and method for controlling a ripple current sensing motor. An apparatus for controlling a ripple current sensing motor may include a first shunt resistor having one end connected to one end of a motor and the other end of the first shunt resistor connected to a ground, a second shunt resistor having one end connected to the other end of the motor and the other end of the second shunt resistor connected to the ground, a first amplifying circuit amplifying a first signal from one end of the motor, a second amplifying circuit amplifying a second signal from the other end of the motor, and a detector detecting a rotation amount and a rotation direction of the motor using a change in voltages of a first detection signal from the first amplifying circuit and a second detection signal from the second amplifying circuit.

A system that applies a counteracting voltage or current to a rotating shaft to minimize a grounding voltage signal of the shaft, measures and analyzes the counteracting signal, and provides expert system logic that compares prior learned waveforms and models of baseline, fault, and degradation waveforms to operational waveforms to determine and predict faults and degradation events. Self-learning logic analyzes the operational waveforms to look for changes, and finds or predicts fault and degradation events in relation to archived characteristics of earlier waveforms. It then adds characteristics of predictive waveforms to the database of model waveforms, and updates rules and thresholds in the expert logic based on the found predictors. It may further calculate and continuously refine a counteracting signal waveform to minimize the shaft grounding waveform.

A system that applies a counteracting voltage or current to a rotating shaft to minimize a grounding voltage signal of the shaft, measures and analyzes the counteracting signal, and provides expert system logic that compares prior learned waveforms and models of baseline, fault, and degradation waveforms to operational waveforms to determine and predict faults and degradation events. Self-learning logic analyzes the operational waveforms to look for changes, and finds or predicts fault and degradation events in relation to archived characteristics of earlier waveforms. It then adds characteristics of predictive waveforms to the database of model waveforms, and updates rules and thresholds in the expert logic based on the found predictors. It may further calculate and continuously refine a counteracting signal waveform to minimize the shaft grounding waveform.

Techniques and examples pertaining to variation calibration for envelope tracking on chip are described. Envelope tracking (ET) statistics among multiple wireless-capable mobile devices (e.g., smartphones) may be collected in laboratory. Optimal ET parameters may be determined based on ET statistics. An ET setting file may be generated for ET factory calibration. In production lines, the ET setting file may be loaded into each mobile device for ET factory calibration.

Techniques and examples pertaining to variation calibration for envelope tracking on chip are described. Envelope tracking (ET) statistics among multiple wireless-capable mobile devices (e.g., smartphones) may be collected in laboratory. Optimal ET parameters may be determined based on ET statistics. An ET setting file may be generated for ET factory calibration. In production lines, the ET setting file may be loaded into each mobile device for ET factory calibration.

A measuring system for measuring a high frequency signal is provided. The measuring system comprises an antenna module, adapted for receiving the high frequency signal. Moreover, the system comprises a detector module adapted for deriving a measuring signal from the high frequency signal. Finally, the system comprises a sensor module adapted for measuring the measuring signal. The sensor module is arranged in a housing, while the detector module is not arranged in the housing. The detector module is connected to the sensor module by a first cable, which is adapted to transmit the measuring signal from the detector module to the sensor module.

A squelch detector, including: an input configured to receive an input signal; a peak detector connected to the input configured to detect a maximum value of the input signal wherein the peak detector includes a refresh input configured to receive a refresh signal to refresh the output of the peak detector, a valley detector connected to the input configured to detect a minimum value of the input signal wherein the valley detector includes a refresh input configured to receive the refresh signal to refresh the output of the valley detector, and a comparator including a first signal input connected to an output of the peak detector, a second input connected to an output of the valley detector, and a first reference input, wherein the comparator is configured to compare a difference between an output of the peak detector and an output of the valley detector and a reference value received at the first reference input and configured to produce an output based upon the comparison.

A fast algorithm is used to study the transient behavior due to the step-like pulse. This algorithm consists of two parts: The algorithm I reduces the computational complexity to T.sup.0N.sup.3 for large systems as long as T<N; The algorithm II employs the fast multipole technique and achieves scaling T.sup.0N.sup.3whenever T<N.sup.2 beyond which it becomes T log.sub.2 N for even longer time. Hence it is of order O(1) if T<N.sup.2. Benchmark calculation has been done on graphene nanoribbons with N=10.sup.4 and T=10.sup.8. This new algorithm allows many large scale transient problems to be solved, including magnetic tunneling junctions and ferroelectric tunneling junctions that could not be achieved before.