Abstract: A bridgeless PFC (power factor correction) converter with improved efficiency is disclosed. The bridgeless PFC converter comprises: a first input terminal and a second input terminal configured to receive an input AC signal; an output terminal; an inductor set comprising N inductors, wherein a first terminal of each inductor is coupled to the first input terminal; and an output stage comprising (N+1) switching circuits coupled between the output terminal and a ground node.

Abstract: An integrated circuit for implementing a switch-mode power converter is disclosed. The integrated circuit comprises at least a first semiconductor die having an electrically quiet surface, a second semiconductor die for controlling the operation of said first semiconductor die stacked on said first semiconductor die having said electrically quiet surface and a lead frame structure for supporting said first semiconductor die and electrically coupling said first and second semiconductor dies to external circuitry.

Abstract: The present technology is generally related to LED bypass circuits and associated methods of operation. In one embodiment, an LED bypass circuit includes a monitoring circuit and a bypass switch. The monitoring circuit is coupled to the LED to monitor the differential voltage across the LED. The bypass switch is coupled to the LED in parallel. When an open status is detected by the monitoring circuit, the bypass switch is turned on to bypass the LED.

Abstract: A current balance scheme for driving LED strings is disclosed. A power supply unit provides a driving voltage to drive a plurality of LED strings. A feedback selector is configured to select a minimum feedback signal indicative of the driving voltage to the power supply unit for regulating the driving voltage. Based on the minimum feedback signal, the driving voltage gets a minimum value to sufficiently drive the plurality of LED strings. A protection circuit is configured to protect the current balance circuit from high voltage especially when there is a shorted LED string.

Abstract: A connector assembly according to embodiments of the present disclosure is advantageously configured to allow a sensor connector to straightforwardly and efficiently join with and detach from a patient cable connector. Further, embodiments of the connector assembly advantageously reduce un-shielded area in an electrical connection between a patient cable and a sensor connector. In addition, embodiments of the connector assembly advantageously increase the shielding of detector signals coming from the patient sensor to the monitor.

Abstract: A contract management mechanism is disclosed for managing contracts in the software licensing arena. The management mechanism may be used, for example, to manage one or more fulfillment contracts. In operation (assuming a software licensing implementation for the sake of example), the management mechanism receives an inquiry regarding licensing of a particular set of software under a particular contract (the contract entitles a customer to consume a certain quota of resources under the contract). In response to the inquiry, the management mechanism determines a licensing amount. This licensing amount may be determined based upon many factors, including the set of software selected, other parameters specified in the inquiry, and the terms associated with the contract. Once the licensing amount is determined, and the customer commits to licensing the software, the management mechanism reduces the quota parameter of the contract by the licensing amount and allows the software to be used under the contract.

Abstract: An input surge suppression device and method that uses a simple JFET structure. The JFET has its gate clamped to a predetermined value, its the drain receives the input voltage from an input power source, its source is connected to the input of a down-stream device, and a resistor connected between the drain and the gate or between the source and the gate. Thus, when the drain voltage approximates the clamped gate voltage, the source voltage nearly equals the drain voltage. When the drain voltage rises above the clamped gate voltage, the source voltage is lower than the drain voltage. The downstream device may be a DC-DC converter and the gate is biased by the enable (EN) pin of a DC-DC converter.

Abstract: A CCFL inverter circuit integrates a feedback circuit and protection circuit together. For both in-phase and out-of-phase applications, sensed lamp voltages can be used for open lamp and short lamp detection and sensed currents can be used for open lamp detection. The driving circuit adjusts the open lamp frequency by using a duty cycle control signal so that the driving circuit can always achieve the desired lamp voltage gain.

Abstract: The present technology discloses a package for a synchronous rectifier module, and also discloses synchronous rectification circuits and power supply adapters. The synchronous rectification circuit co-packages the synchronous rectifier and the driver into one single package. The single package simplifies the external circuitry and reduces potential electromagnetic interferences.

Abstract: A tracking system for use with a pipeline includes a scraper having signal generation capability for generating acoustic signals, a plurality of acoustic pressure sensors positioned at intervals along the path travelled by the scraper, and a plurality of local processors positioned at intervals along the path travelled by the scraper. Each of the local processors is in communication with a respective acoustic pressure sensor. A central processor is in communication with the local processors and determines the location of the scraper using time-stamped acoustic signals received by the pressure sensors and a speed of sound in a fluid within the pipeline.

Abstract: An LED backlight circuit includes a transformer that takes a high voltage from a high voltage bus on a first winding. Current induced on a second winding of the transformer charges an energy storage capacitor. Energy stored in the energy storage capacitor drives a single string of series-connected LEDs to provide backlighting to an LCD panel. The high voltage may be taken directly off an output of a power factor correction circuit.

Abstract: A system for detecting and locating leaks includes a pipeline, strain sensors positioned on the external surface of the pipeline, acoustic pressure sensors positioned at intervals along the pipeline, local processors connected to the strain sensors and acoustic pressure sensors, and a central processor connected to the local processors. The strain sensors measure a strain on the external surface of the pipeline indicative of changes in the pressure of the fluid within the pipeline. The acoustic pressure sensors sense acoustic signals within the pipline. Sensed acoustic pressure signals and sensed strain measurements are compared to each other and to stored profiles to detect and locate leaks.

Abstract: The present invention discloses a double-edge pulse width modulation (PWM) controller based on the output current and output voltage which is modulated in real time by the output current and the output voltage. The controller uses an extra first adder to sum up the compensation signal and a triangular signal (or a saw-tooth signal); a second adder to sum up the output current signal to a bias value; a PWM comparator, with its non-inverting input receiving the output of said first adder, its inverting input receiving the output of said second adder and outputs the PWM signal.

Abstract: An embodiment of the present disclosure provides a noninvasive optical sensor or probe including disposable and reusable components. The assembly of the disposable and reusable components is straightforward, along with the disassembly thereof. During application to a measurement site, the assembled sensor is advantageously secured together while the componentry is advantageously properly positioned.

Abstract: A dual ended driver circuit for a LCD backlight is disclosed. The circuit comprises a master board and a slave board, which provides a first output drive signal and a second output drive signal to either end of a lamp set, respectively. The circuit only uses one control chip to synchronize and make symmetrical the first output drive signal and the second output drive signal.

Abstract: The present invention discloses a DC/AC converter in the backlight power supply system using cold cathode fluorescent lamp (CCFL). The DC/AC converter comprises a front end DC/DC converter, a full-bridge or half bridge inverter, and a piezoelectric transformer. Even with a wide range of input voltages, the front end DC/DC converter produces a predetermined DC voltage or a DC voltage with a predetermined small range and the cascaded inverter operates with a switching frequency close to the resonant frequency of the piezoelectric transformer, which helps the backlight power supply system achieve high efficiency.

Abstract: A circuit for controlling the switch frequency of an inverter that strikes and drives fluorescent lamps is disclosed. The circuit comprises a frequency generator and an offset circuit. The offset circuit provides a current signal in response to the lamp status. The frequency generator provides a frequency control signal in respond to the current signal so as to control the switch frequency of the inverter. When the lamp is open, the switch frequency of the inverter is higher; when the lamp is lighted, the switch frequency of the inverter is lower.

Abstract: The present invention discloses a multi-die package which facilitates heat dissipation for a high power consumption die. In the package, part of the lead frame is bent so as to be exposed at the surface of the package. On the opposite side of the exposed surface, a high power consumption die is attached. The other die with lower power consumption is not at the surface of the multi-die package.

Abstract: An input surge suppression device and method that uses a simple JFET structure. The JFET has its gate clamped to a predetermined value, its the drain receives the input voltage from an input power source, its source is connected to the input of a down-stream device, and a resistor connected between the drain and the gate or between the source and the gate. Thus, when the drain voltage approximates the clamped gate voltage, the source voltage nearly equals the drain voltage. When the drain voltage rises above the clamped gate voltage, the source voltage is lower than the drain voltage. The downstream device may be a DC-DC converter and the gate is biased by the enable (EN) pin of a DC-DC converter.