Abstract: A relaxation oscillator for generating an oscillator output signal having a predetermined frequency. The relaxation oscillator includes an interleaved charge pump for providing a restoring charge to an integrator in response to at least one charge pump control signal. The relaxation oscillator further includes an integrator having an integrator input connected to the current summing node. The integrator is adapted to produce an integrator output signal having the predetermined frequency at an integrator output. A comparator having an input connected to the integrator output is adapted to generate the oscillator output signal having the predetermined frequency in response to the integrator output signal.

Abstract: A watt-hour meter employs a power factor compensation technique that inserts a delay into the digitized current or voltage sample stream. An exemplary embodiment of the present invention includes an electronic watt-hour meter comprising a voltage sensor, a current sensor, a conversion circuit, and a processing circuit: The voltage sensor generates a voltage measurement signal responsive to a voltage provided to a load. Similarly, the current sensor generates a current measurement signal responsive to a current provided to a load. The conversion circuit further comprises: a first converter connected to the voltage sensor for generating sampled voltage data stream based on said voltage measurement signal; a second converter connected to the current sensor for generating a sampled current data stream based on said current measurement signal, and a phase correction circuit.

Abstract: An integrated circuit including one or more power devices, and circuitry which reliably (and independently) shuts down each power device that is detected to be in an undesired operating condition (e.g., one or both of an overcurrent condition and an overvoltage condition) that causes a thermal fault, but which does not shut down any power device that is not in such undesired operating condition. In typical implementations in which the integrated circuit has multiple power devices and an overvoltage detection circuit for each power device, the integrated circuit includes a thermal fault detection circuit and logic circuitry which receives the output of the thermal fault detection circuit and each overvoltage detection circuit. The logic circuitry generates signals which shut down appropriate ones of the power devices in response to the thermal fault detection and overvoltage detection signals it receives.

Abstract: A structure and process are provided for converting DC-DC voltages, which allows both buck and boost conversion utilizing a single switched capacitor array. In one embodiment of this invention, the switched capacitor array comprises multiple gain blocks, where the gain blocks are identical and stacked upon each other. The switches and capacitors are configured so that various combinations of series and parallel capacitor connections are possible, and thus both buck and boost conversions are attainable with one switched capacitor array. Other embodiments of the present invention use multiple gain blocks, configured such that the capacitor in each gain block can be connected to ground. As a result, a single charge state for a range of desired gains can be configured for use with a shared or common rest state, i.e., a capacitor configuration which is the same regardless of the desired gain.

Abstract: A structure and method are provided for converting unregulated DC voltages to regulated DC voltages using pulse frequency modulation (PFM) and a switched capacitor array capable of multiple gains, where gain selection is based on the output voltage. The selected gain is maintained at or above a minimum gain determined from the input voltage. A regulated voltage, which is equal to or greater than a desired output voltage, is thus available to the load over a wider range of inputs and with greater conversion efficiency.

Abstract: A tool for use as an aid in emptying waste fluid from a reservoir to a waste container. This tool is a funnel shaped device having a large circular opening for entrance of waste fluid. A funnel wall extends from the larger opening to a smaller opening, preferably offset from the larger circular opening. Access to the funnel interior is provided through the funnel wall, serving as a guide and seal for passage of a wrench extension. The end of the extension is preferably a standard 3/8" square drive plug for mounting an appropriately sized 3/8" drive socket or plug for removal of the reservoir drain plug. The choice of socket or plug to be mounted to the extension depends on the configuration of the drain plug. The opposite end of the wrench extension has a socket for adapting to a preferred 3/8" driver. In operation, the wrench extension is passed through the access to the funnel interior, and the appropriate sized socket or plug is placed on the 3/8" drive end of the wrench extension.

Abstract: The present invention discloses method and apparatus for offset and phase correction in multiplexed delta-sigma modulators. According to the invention, offsets and phases of input signals to multiplexed delta-sigma modulators are corrected by a simple and low cost method. The invention utilizes a novel switching technique during different sampling periods to eliminate the effect of DC offsets present in multiplexed input signals. The invention also uses a delay introduced by a FIFO or a shift register to individually correct for phase shifts present in individual multiplexed input signals. The invention accomplishes these objectives without introducing a significant quantization noise, and without requiring overlapping FIR filters.

Abstract: A programmable system synchronizes the operation of an electronic angular position indicator with the angular displacement of a rotor. The system can synchronize operation with rotors with non-uniform mark spacing. A sensor provides the system with electronic pulse patterns corresponding to marks on the rotor. Pulse patterns are compared to patterns stored in memory to determine the instantaneous angular position of the rotor. The synchronization system provides the angular position indicator with parameters appropriate to the angular position of the rotor. The system obtains synchronization during initial rotations of the rotor and continually checks synchronization during subsequent rotation.

Abstract: The present invention provides dynamic hysteresis for threshold detection circuitry. The hysteresis decay pattern, rate of decay, and minimum separation between the HSP and LSP are programmable. In particular, the hysteresis decay pattern may be programmed, in any manner, so that it has a better correlation to the amplitude of the input signal. The preferred embodiment of the present invention includes a comparator circuit, digital logic, and a digital-to-analog converter circuit. The comparator circuit has a fixed LSP and a programmable HSP for detecting threshold crossings of the input signal in order to accurately generate a pulse train. The HSP includes hysteresis for providing greater immunity to noise for an input signal having an amplitude which varies with frequency. The hysteresis of the HSP decays linearly at a programmable rate unlike prior art threshold detectors having a fixed rate of exponential decay determined by resistor and capacitor values.

Abstract: A programmable, electronic, angular position indicator, based upon engineering units, estimates the angular displacement of a rotating rotor. The angular position indicator is programmed with the particular arrangement of teeth (or other markings) on the rotor. Intermediate angular displacements are interpolated between a limited number of positive angular displacement indications. Offsets, due to acceleration or deceleration of the rotor, are corrected at each positive angular displacement indication without skipping the output of each interpolated angular displacement. Angular displacement is determined in standard engineering units.