Koninklijke Philips Corporation N.V.

Philips Electronics North America Corporation

Jerome E Liebler

Alma Stephenson Anderson

The present invention provides an improved measuring circuit for measuring a current of an inductor with minimum losses and errors. According to one embodiment of the invention, the measuring circuit comprises an op-amp, a RC network connected in a feedback loop of the op-amp, and a scaling resistor connected in series to one of the input terminals of the op-amp. By setting the RC constant of the RC network to be equal to the ratio of the inductor value over its internal resistance value, the inductor current can be derived independent of the frequencies of AC signals.

Method and apparatus for near losslessly measuring inductor current

A buck converter has an input circuit for receiving an input signal, a controller connected to and controlling the input circuit, a switch controllable by the controller for switching on/off, a current storage element connected to the input circuit and the switch, and an output voltage storage element connected to the current storage element for connecting in parallel with a load. In a charging phase, the controller causes (a) the input circuit to allow the input signal to pass through for provision to the load via the current storage element and (b) the switch to switch off (becoming an open circuit). In a discharging phase, the controller causes (a) the input circuit to decouple from the input signal and (b) the switch to switch on (become a short circuit), so that (c) current flows within a loop formed by the switch and the current storage element.

Buck regulator with ability to handle rapid reduction of load current

In a power converter for supplying a controlled output from an input supply, a plurality of transfer devices is used to selectively couple the input supply to a distribution of storage devices. In a high-current mode, each of the transfer devices and associated storage device is used to couple the input supply to the controlled output. In a minimal-current mode, each of the transfer devices and associated storage device is selectively disabled until only one transfer device and storage device is utilized, and this remaining device may also be selectively disabled. Because the storage devices are distributed, each storage device can be smaller than that required for the high-current operation, thereby minimizing the losses associated with high-current switching converters during low-current operation. In another aspect of this invention, the plurality of transfer devices is operated at different phases to one another, thereby reducing the ripple associated with high-current operation. In another aspect of this invention, the storage devices are each sized for efficient operation at a given load level.

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North Plains, OR, United States of America

Jerome E Liebler