Abstract: A power management device for enabling multiply power sources to supply power to a load. The power management device includes a plurality of switches and a control logic. The plurality of switches are coupled to a plurality of power sources respectively and each switch coupled to each power source. The control logic is capable of selecting a set of switches among the plurality of switches to cooperate in a time-divided fashion to allow the power sources to provide power to the load. The set of switches is selected based on an electrical requirement of the load and an electrical condition of each switch.

Abstract: A driver package includes an integrated circuit (IC) comprising pull up circuitry capable of turning ON an associated switch and pull down circuitry capable of turning OFF the associated switch. The pull up circuitry may be coupled to a first bonding pad of the IC, and the pull down circuitry may be coupled to a second bonding pad of the IC. The driver package may further comprise a first conductive path coupled between the first bonding pad and a package pin of the driver package, where the package pin is coupled to the associated switch, and a second conductive path coupled between the second bonding pad and the package pin. The first conductive path may further provide a sensed signal representative of state of the associated switch to break before make control circuitry to assist in minimizing a break before make delay time interval.

Abstract: An audio controller for use with laptop and notebook digital computers for reproducing compressed digital audio recordings. The controller includes a drive interface for traversing and accessing audio data files stored on a drive of a computer system. Function keys coupled to the controller permit users to access drives containing desired audio data. The selected audio data is read from the drive into the controller. Decoding circuitry decodes the audio data and generates a decoded audio data stream. The data stream can be converted to an analog signal by the controller, or sent to the audio subsystem of the computer system. Advantageously, the controller operates when the computer system is in an inactive state, for example in power saving mode or OFF, and operates in passthrough mode when the computer system is ON or active.

Abstract: A capacitor charging circuit comprises, power transfer circuitry, power switching control circuitry and voltage measurement circuitry. The power transfer circuitry transfers power from a power source to a capacitor. The power switching control circuitry controls the switching that causes power to be delivered to the power transfer circuitry. The voltage measurement circuitry indirectly measures the output voltage to determine when to stop charging the capacitor.

Abstract: A liquid crystal display system and CCFL power converter circuit is provided using a high-efficiency zero-voltage-switching technique that eliminates switching losses associated with the power MOSFETs. An optimal sweeping-frequency technique is used in the CCFL ignition by accounting for the parasitic capacitance in the resonant tank circuit. Additionally, the circuit is self-learning and is adapted to determine the optimum operating frequency for the circuit with a given load. An over-voltage protection circuit can also be provided to ensure that the circuit components are protected in the case of open-lamp condition.

Abstract: A PC Card subsystem is used for coupling a PC card to a computer system and comprises a PC Card controller and a PC Card power switch. The PC Card controller is coupled to and operates the PC card. The PC Card power switch is used for supplying power to the PC Card and provides at least one control signal for operating the PC card.

Abstract: A circuit according to the present invention is used for driving a photoflash diode and comprises a current sink, a feedback circuit, and a DC-DC converter. The current sink is coupled to the photoflash diode for controlling the current through the photoflash diode. The feedback circuit receives a feedback signal indicative of the electrical condition of said first current regulator. The DC-DC converter is coupled to an external power source and the feedback circuit for powering the photoflash diode so as to control the electrical condition of the current sink to a predetermined value.

Abstract: A circuit is used for driving a plurality of LEDs by an external voltage source. The LEDs are coupled in series. The circuit comprises a plurality of switches coupled to the LEDs in parallel, respectively, for individually controlling the brightness of the LEDs. The circuit further includes a plurality of Pulse-Width Modulation (PWM) signals coupled to the switches, respectively, for individually controlling the switches.

Abstract: A computer capable of playing real time applications includes a processing circuit configured to operate in a first power state, a second power state, and a third power state where the processing circuit consumes less power in the second state than in the first state, and less power in the third state than in the second state; and a real time subsystem coupled to the processing circuit, wherein the real time subsystem includes a buffer. The buffer is further configured to store data and output the data to an output device thereby enabling the processing circuit to enter the third power state while the buffer is outputting said data.

Abstract: A smart card virtual hub combines an ISO7816 compliant smart card reader interface with a USB hub that provides one or more attachment points for connection of devices to the USB bus, thereby interfacing such devices to the host computer. The hub in the presently preferred embodiment of the invention provides one port to which one USB functional device, such as a keyboard, may be attached. The attached keyboard shares a common USB bus bandwidth with the internal embedded smart card reader through a host-scheduled, token-based communication protocol that is handled by the USB driver and the device driver.

Abstract: The present invention is a LDO voltage regulator circuit with common-mode feedback. The LDO voltage regulator includes an error amplifier with a common-mode feedback unit, a pass device and a compensation circuit. A signal from the pass device acts as an input signal to the error amplifier and is compared with another input signal, producing a differential signal. The differential signal is amplified and then provided to the pass device. A capacitor in the compensation unit provides frequency compensation to the LDO voltage regulator. The common-mode feedback unit incorporated into the error amplifier greatly improves a slew rate of a gate voltage of the pass device.

Abstract: A method according to one embodiment may include supplying power to plurality of External Electrode Fluorescent Lamps (EEFLs). The method of this embodiment may also include generating signals proportional to the voltage of each EEFL. The method of this embodiment may also include generating a feedback signal indicative of the state of one or more of the plurality of EEFLs based on, at least in part, the value of at least one signal proportional to the voltage of each EEFL. Of course, many alternatives, variations, and modifications are possible without departing from this embodiment.

Abstract: A switched bridge circuit comprises a first switch, a second switch, and a non-overlapping pulse generator. The first switch is coupled to a load. The second switch is coupled to said load. The non-overlapping pulse generator is coupled to the first switch and the second switch and coupled to receive an input signal. The non-overlapping pulse generator in response to the input signal generates a first control signal and a second control signal that respectively control the first and second switches. The pulses in the first and second control signals are not overlapped so that the first and second switches are not simultaneously enabled.

Abstract: A DC to DC controller for controlling an inrush current from a DC to DC converter to a battery system having an internal isolating switch. The DC to DC controller is configured to control the DC to DC converter based on a state of the internal isolating switch. If the switch is open, the DC to DC controller adjusts the output voltage of the DC to DC converter to a predetermined voltage level. Based on the value of such voltage level, in rush current from the DC to DC converter to the battery system can be reduced or eliminated when the isolating switch changes from an open state to a closed state. An electronic device including such a DC to DC controller is provided. Related methods for controlling inrush current are also provided.

Abstract: A DC/DC converter for converting an input voltage to an output voltage comprises a switch, an inductor, two voltage dividers, a capacitor, and a controller. The switch coupled to the input voltage. The inductor having a parasitic direct current resistance is used for coupling the switch to an output node of the DC/DC converter so as to generate the output voltage at the output node. The first voltage divider is coupled to the output node for generating a divided voltage of the output voltage. The second voltage divider is coupled to the switch and ground. The capacitor coupled to the first voltage divider and the second divider to measure the current through the inductor by sensing a voltage across the capacitor. The controller coupled to the first switch for enabling and disenabling it so as to discontinuously providing power from the input voltage to the inductor.

Abstract: An analog to digital converter may include an input switch array configured to alternately sample a first and a second input signal to a first and a second input capacitor during two different sample time intervals, an integrator having a first and second integration capacitor, and a cross switch array coupled to the input switch array and the integrator. The cross switch array may be configured to alternately transfer charges from the first and second input capacitors to the first and second integration capacitors during two different transfer time intervals. A system including an analog to digital converter consistent with an embodiment and an associated method of sampling and transferring charges in an analog to digital converter are also provided.

Abstract: The present invention provides systems and methods to operate a PC as an alarm clock. An IC is provided to monitor the power status of PC and generate an alarm clock event at a preselected time. The alarm clock event includes a variety of operations, for example, powering on or off the PC system or controlling an AM/FM or TV module.

Abstract: A cardbus controller is provided that reduces signal count and board area. In one exemplary embodiment, the controller is adapted to multiplex selected signals in a two PC Card system so that signal lines are not repeated. The selected signals may include common signals between two PC Cards. The controller may also include early detection circuitry, arbitration circuitry and power management circuitry to more effectively operate two PC Cards. In other exemplary embodiments, the invention provides a method of reducing the chip area of a PC Card controller integrated circuit by mapping an internal IDSEL signal to an external address line.

Abstract: An inverter controller for an LCD panel display with automatic brightness adjustment circuitry is provided. In one exemplary embodiment, the controller includes a look-up table that receives a signal indicative of the ambient light around the LCD panel and generates a signal corresponding to desired panel brightness. The signal corresponding to the desired panel brightness is, in turn, used as a threshold signal in a conventional feedback inverter topology supplying power to lamps associated with the LCD panel. In another exemplary embodiment, a master controller is provided that includes a light sensor controller to poll a slave light sensor to generate a signal indicative of the ambient light around the LCD panel.

Abstract: The present invention provides a driving circuit for driving a light source. The driving circuit includes a serial-arranged transformers system having multiple primary windings and secondary windings; a first switch conducting current though a first path and a second switch conducting current though a second path. The first path is a first set of primary windings connected in series and the second path is a second set of primary windings connected in series and the first set of primary transformer windings and the second set of primary transformer windings form the dual primary windings of the transformers respectively. Based on the conduction of each switch, a DC voltage source supplies power to the primary windings of the transformers, which in turn powers on the light source connected to the secondary windings of the transformers.