Arques Technology, Inc.

Other

Semtech Corporation

Micro International Limited

O.sub.2 Micro, Inc.

Arquesttechnology, Inc.

Kwang H Liu

Sorin Laurentiu Negru

Fu-Yuan Shih

Terry J Groom

George Hsieh

Sterling D Du

Yung Lin Lin

Stuart Pullen

You-Yuh Jack Shyr

John Chou

Te-Jen Hsieh

Frank Shih

Scott Wu

Jacky Chen

An integrated circuit (IC) has logic and timing circuits that are coupled to discrete circuitry to provide protection and indications whenever an AC adapter that is faulty or has improper voltage levels or polarity are plugged into a system. In particular, the IC device provides over-voltage, under-voltage, and reversed-polarity protections to an electronic system to keep the electronic system from being damaged by an alternating current (AC) adapter having an improper voltage range or voltage polarity. It also provides a protection that prevents an adapter from powering a host system that has a short-circuit fault.

Power adapter interface circuitry for protecting a battery operated system

A dual-output voltage regulator is disclosed, which provides a first terminal voltage and a second terminal voltage to DDR DRAM. The dual-output voltage regulator comprises a first regulator unit for receiving an input voltage and providing the first terminal voltage via a first transistor unit; and a second regulator unit for receiving the input voltage and the first terminal voltage in order to output the second terminal voltage, wherein the second terminal voltage is half of the first terminal voltage.

Dual-output voltage regulator

A gate drive supply circuit generating a high-level supply voltage and a low-level supply voltage for driving N-type high-side and low-side power MOSFETs in a multiple-output, low-voltage DC-DC converter integrated circuit. The gate drive supply circuit includes a boost regulator for generating the low-level supply voltage and a charge pump doubler for generating the high-level supply voltage. Both the high-level supply voltage and the low-level supply voltage are distributed to one or more regulators, including but not limited to buck or boost type regulators.

Biasing system and method for low voltage DC&#x2014;DC converters with built-in N-FETs

A charging system that concurrently charges a main system and a battery for powering the main system when the charging system is connected to an adapter. The charging system includes a current sensing resistor, a first current control circuit for regulating the current in a linear battery charger and a second current control circuit for controlling the maximum adapter current. The charging system further includes a first temperature control circuit for regulating the current in the battery charger and a second temperature control circuit for controlling the maximum power dissipation of the charging system. The charging system further includes a linear regulator for providing power to the main system from the adapter and a main system voltage control circuit and a battery voltage control circuit. The charging system apportions the adapter current between the main system and the battery charger giving priority to the main system.

Charger system with dual-level current regulation and dual-level thermal regulation

A power converter including a first stage, a reservoir capacitor and a second stage. The first stage converts the voltage of a primary energy source, such as a battery, to a voltage on the reservoir capacitor, which stores a large amount of energy in the form of a voltage substantially larger than the voltage of the primary energy source. The second stage converts the voltage on the reservoir capacitor to a substantially constant voltage for a load device that demands current having the form of large, short, current pulses. The cascaded converter prevents the pulsating load currents of the load device, such as a GSM power amplifier, from causing a severe voltage loss at the battery. This increases the power available from the battery and reduces loses from the internal resistance of the battery.

Boost-buck cascade converter for pulsating loads

A voltage regulator for providing a bidirectional current and a regulated voltage to a load. The voltage regulator regulates the output voltage at one half the level of the input voltage using a voltage doubler circuit in reverse. The regulator provides current to the load when the output voltage drops and receives current from the load when the output voltage rises. The voltage regulator is particularly suited to supplying a termination voltage to multiple line drivers in a DDR DRAM system, where the line drives require an active termination voltage to reduce power. Additionally, a pair of linear regulators, one for clamping the output voltage at a predetermined low voltage level and for supplying additional current demanded by the load, and the other for clamping the output voltage at a predetermined high voltage level and for receiving additional current supplied by the load, is included.

Bidirectional voltage regulator sourcing and sinking current for line termination

A ripple-mode controller provides reliable operation in multi-phase power supply circuits, over a variety of operating conditions. Cross-phase blanking allows the controller to preserve the desired phase relationship between the switching pulses its provides to the different output phases, and permits the controller to operate each output phase at nearly 100% duty cycles. Active current sharing compliments blanking operations by adjusting the width of switching pulses the controller provides to one or more of the output phases based on detecting load current imbalances between the different output phases. With active current sharing, the controller prevents one or more output phases from carrying excessive portions of the load current. Further complimenting its operation, the controller may include virtual ripple generation to increase the noise immunity of its ripple-mode regulation.

Self-clocking multiphase power supply controller

Decorative fluorescent lamp and lamp fixture

An embodiment of a dual-channel switching power system comprises a standby power supply and a main power supply both regulated by an eight-pin control chip. The control chip generates two sets of pulse-width modulation signal from a common clock oscillator and regulates the two power supplies during alternate clock cycles. The switching frequency and over-current limits of the two power supplies are adjustable by selecting different resistance values for two external resistors. The control chip provides an independent over-current protection to each power supply by monitoring the input power flow of the two power supplies via a common current-sense resistor.

Dual-channel power system with an eight-pin PWM control chip

A controller for a smart battery selector included in a portable device has a plurality of switch-drivers at least equal to a plurality of smart batteries. The batteries provide battery-state data via a bus to a host computer included in the portable device. Each switch-driver effects selection of an associated battery. A control electronic-circuit in the controller directs operation of the switch-drivers for selecting the battery so that at any instant only one battery powers the portable device. A bus-snooper circuit permits the controller to independently monitor the bus for battery-condition alarm-messages. The controller may respond to such messages by selecting a different battery. The controller may also select a single battery for recharging, and may terminate charging upon receiving a battery overcharge message.

Smart battery selector offering power conversion internally within a

An electrical circuit for simultaneously energizing at least a pair of CCFLs that are connected in series. The circuit also includes a transformer having a primary winding adapted to receive an alternating current. A secondary winding is coupled in series with the CCFLs to energize their operation. A shunt capacitor, connected in parallel across one CCFL, significantly reduces the peak voltage that must be applied across the CCFLs. Usually, the circuit also includes an isolation capacitor connected in series between the CCFLs and the secondary winding of the transformer. The isolation capacitor provides both DC blocking and electrical isolation between the secondary winding and the CCFLs.

Circuit for energizing cold-cathode fluorescent lamps

A switched-mode power supply for energizing a cold-cathode fluorescent lamp ('CCFL') includes a first semiconductor switch connects in series with a primary winding of a step-up transformer. The primary winding and a secondary winding, having many more turns than the primary winding, are disposed about a transformer core which has a linear magnetic permeability. A series connected second semiconductor switch and capacitor connect in parallel with the transformer's primary winding. A controller circuit transmits signals to turn the switches on and off. The controller circuit turns the first and second semiconductor switches on and off at a frequency that is higher than a resonant frequency of a parallel resonant circuit formed by the primary inductance of the transformer and capacitance of the capacitor. A decoupling capacitor connects in series to a first end of the transformer's secondary winding. A second terminal of the decoupling capacitor and a second end of the secondary winding provide ac power output terminals for the switched-mode power supply across which a CCFL may be connected.

Growing community of inventors

Sunnyvale, CA, United States of America

Kwang H Liu