Abstract: A method and circuit for managing thermal performance of an integrated circuit. Temperature sensing circuits and a plurality of power FETs that are coupled together in parallel are manufactured from a semiconductor substrate. Each temperature sensing circuit monitors the temperature of the portion of the semiconductor substrate near or including a corresponding power FET. When the temperature of the semiconductor substrate near one or more of the power FETs reaches a predetermined value, the corresponding temperature sensing circuit reduces a voltage appearing on the gate of the power FET. The reduced voltage increases the on-resistance of the power FET and channels a portion of its current to others of the plurality of power FETs. The power FET continues operating but with a reduced current flow. When the temperature of the semiconductor substrate falls below the predetermined value, the gate voltage of the power FET is increased to its nominal value.

Abstract: In one embodiment, an in-rush limiter is configured to control an output voltage to increase at a rate that is independent of the load that is powered by the in-rush limiter.

Abstract: In one embodiment, an LED system is controlled to have a substantially unity power factor.

Abstract: In one embodiment, an LED system is controlled to have a substantially unity power factor.

Abstract: In one embodiment, a vertical N-channel transistor is coupled in a high side configuration to control a current through an LED.

Abstract: In one embodiment, a capacitor of a charge pump circuit is referenced to a high side voltage or top voltage rail.

Abstract: In one embodiment, a diagnostic circuit is used to test the on-resistance of a transistor.

Abstract: In one embodiment, a self-gated transistor includes a sensing portion that generates a sense signal that is used to drive the self-gated transistor.

Abstract: In one embodiment, a capacitor of a charge pump circuit is referenced to a high side voltage or top voltage rail.

Abstract: An inrush current limiter circuit (20) includes a mirrored transistor (50) responsive to a control signal (VDRIVE) developed from a sense current (ISENSE), and has a first source (51) coupled to a supply voltage, a common drain (53) that routes a load current (ILOAD) to an output node (45), and a second source that samples the load current to produce the sense current. A fault protection circuit (64) disables the mirrored transistor in response to a first fault condition (TEMP, UVLO) and is coupled to a first lead (43) for externally adjusting a fault threshold. A fault communication circuit (250) is coupled to the first lead to receive a fault signal representative of an external fault condition to disable the mirrored transistor.

Abstract: A power factor correction device (26, 75) stores the output of an error amplifier (32) on a storage element (39). A zero crossing detector (37) detects the zero crossings of the AC input voltage and enables the power factor correction device (26, 75) to adjust the value of the voltage stored on the storage element (39).

Abstract: An inrush current limiter circuit (20) includes a mirrored transistor (50) responsive to a control signal (VDRIVE) developed from a sense current (ISENSE), and has a first source (51) coupled to a supply voltage, a common drain (53) that routes a load current (ILOAD) to an output node (45), and a second source that samples the load current to produce the sense current. A fault protection circuit (64) disables the mirrored transistor in response to a first fault condition (TEMP, UVLO) and is coupled to a first lead (43) for externally adjusting a fault threshold. A fault communication circuit (250) is coupled to the first lead to receive a fault signal representative of an external fault condition to disable the mirrored transistor.

Abstract: A switching power supply (30) includes a compensation circuit (58) which monitors a transformers (36) primary side to provide a voltage compensation signal, COMPV. A transistor inductor current, VTRAN is fed to the compensation circuit (58) to establish a DC level proportional to the peak primary side inductor current flowing through a power transistor (38). VTRAN is fed to a multiplier circuit (98). The output of the multiplier circuit (98) is scaled by a resistor (80) to establish the compensation signal, COMPV at the output to the compensation circuit (58). When at current limit, an amplifier (66) becomes saturated causing a diode (68) to reverse bias, effectively removing compensation signal COMPV from operation. An amplifier (70) falls into a linear region and a diode (74) becomes forward bias forcing compensation signal COMPC into operation providing regulation to the output of the switching power supply (30) at current limit.

Abstract: Abrasive articles comprising abrasive particles and at least one of (a) a reaction product of components comprising a resole phenolic resin and a bisphenol/fornaldehyde resin, (b) a bond system is derived by curing a mixture of a resole phenolic resin and a bisphenol/formaldehyde resin, and/or (c) a bond system comprising polymeric material preparable by combining components comprising a resole phenolic resin and a bisphenol/formaldehyde resin.

Abstract: A liquid level sensor device, particularly adapted for use with corrosive and hazardous liquids such as oil, for measuring the liquid level in a storage tank or vessel. A tubular device is placed vertically in a liquid storage tank and senses the liquid level by having a float embedded with magnets move vertically along the axis of reed switches encased in the tubular device. The device contains temperature sensors to measure the temperature of the tank fluid, and microprocessors that scan the reed switches, transmitting data through a connector in the device top to a nearby computer for recording and transmission to a control and monitoring location. The electrical data system inside the device utilizes only two conductive trace runs throughout the device length to maximize reliability while minimizing the copper used. Special mechanical and electrical assembly connectors inside the device permit the device to flex safely in turbulent liquid conditions, without breakage.