Abstract: An over voltage transient controller to protect a rechargeable battery from an over voltage transient condition. The over voltage transient controller may comprise a comparator to compare a first signal with a second signal representative of a reference voltage level and to provide an output signal representative of an over voltage transient condition to a switch if the first signal is greater than or equal to the second signal. The switch is responsive to the output signal to protect the rechargeable battery from the over voltage transient condition. The over voltage transient controller may further comprise a DAC, wherein the second signal is based, at least in part, on an output of the DAC. An apparatus comprising a charge switch and such an over voltage transient controller is also provided.

Abstract: A DC to DC converter includes a comparator, a driver, and a pair of switches. The comparator compares the output voltage with a reference voltage signal and generates a PWM signal. The driver drives the switches so as to force the output voltage to follow the reference signal. In a multiphase architecture, two or more such converter circuits are incorporated to minimize the output voltage ripple and further reduce the recovery time. In a two-phase architecture, two reference signals are phase-shifted by 180 degrees. In an N-phase architecture, the reference signals are phase-shifted by 360/N degrees.

Abstract: Power supply circuit for LCD backlight and method thereof are disclosed in the present invention. The power supply circuit includes a power bus, a boost converter, a buck converter and a controller. The power bus supplies power to a load. The boost converter and buck converter are coupled to the power bus respectively for storing the power from the power line and restoring the power to the load. A controller is further coupled to the buck and boost converter for enable them alternatively according to a pulse width modulation (PWM) signal.

Abstract: A selector circuit configured to select among a DC power source and a plurality of batteries for an electronic device. The selector circuit is responsive to an output signal from an associated power management unit. The selector circuit is further configured to permit parallel operation of two or more of the batteries. The selector circuit may further act to independently verify power conditions and override instructions from the PMU in certain instances to enhance power supply safety and battery life such as by preventing inter battery current flow from a higher potential battery to a lower potential battery coupled in parallel.

Abstract: A selector circuit configured to select among a DC power source and a plurality of batteries for an electronic device. The selector circuit includes a first comparator configured to compare a first input signal representative of a voltage level of the DC power source with a first threshold level and provide a first output signal representative of a difference between the first input signal and the first threshold level, and a selector output circuit. The selector output circuit is configured to provide selector output signals that control selection among the DC power source and the plurality of batteries. The selector output circuit providing said selector output signals to select the DC source and deselect the plurality of batteries if the first output signal is representative of the voltage level of said DC power source being greater than the first threshold level.

Abstract: The present invention provides a driving circuit with protection function for driving a set of external electrode fluorescent lamps (EEFL). The drive circuit includes: a transformer connected to the set of EEFLs; a switching network connected to the transformer which delivers power to the transformer; a sensing circuit connected to the set of EEFLs which detects disconnection if one light source is disconnected; and a controller connected to the switching network which controls the switching network to reduce the total current supplied to the EEFLs which remain connected, if the sensing circuit detects that one EEFL is disconnected. Appropriate protection can therefore be implemented when the EEFL is disconnected on one end or both ends.

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.

Abstract: A low-power digital audio decoding and playing system and method for computing devices provides a low-cost, low power-consumption, long-battery-life audio playing and decoding system, which may be used to play compressed audio files of various formats. In one aspect, a computer system adapted to play audio files comprises a system CPU, memory, at least one drive comprising compressed audio data, and an audio controller coupled to the system CPU, memory and drive. The audio controller is adapted to cause the drive to read the compressed audio data from the drive, to cause the system CPU to decompress the compressed audio data from the drive into decompressed audio data, to cause the decompressed audio to be stored in the memory, and to cause the decompressed audio data to be retrieved from the memory for playing.

Abstract: A low-power digital audio decoding and playing system and method for computing devices provides a low-cost, low power-consumption, long-battery-life audio playing and decoding system, which may be used to play compressed audio files of various formats. In one aspect, a computer system adapted to play audio files comprises a system CPU, memory, at least one drive comprising compressed audio data, and an audio controller coupled to the system CPU, memory and drive. The audio controller is adapted to cause the drive to read the compressed audio data from the drive, to cause the system CPU to decompress the compressed audio data from the drive into decompressed audio data, to cause the decompressed audio to be stored in the memory, and to cause the decompressed audio data to be retrieved from the memory for playing.

Abstract: A low-power digital audio decoding and playing system and method for computing devices provides a low-cost, low power-consumption, long-battery-life audio playing and decoding system, which may be used to play compressed audio files of various formats. A software only solution for such a system is provided. Various applications including media select applications, voice recording applications, digital device applications, and remote control applications are also provided.

Abstract: A low-power digital audio decoding and playing system and method for computing devices provides a low-cost, low power-consumption, long-battery-life audio playing and decoding system, which may be used to play compressed audio files of various formats. A software only solution for such a system is provided.

Abstract: A 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 reconfigurable flash media reader system provides a flash media reader that accepts both asynchronous and synchronous flash media cards. The reader identifies the card type of the inserted flash media card and notifies the host computer of the card type. The host computer has a list of interface information for different types of flash media cards and references the card type in the list and sets the proper baud rate on the reader. If the flash media card is a synchronous card, data that is to written into the flash media card is gathered and converted to the proper card IO strobes for the card type which are interleaved with the proper card clock strobes for the card type into a bit stream in a bulk transfer packet. The reader extracts the data bit stream from said bulk transfer packet and clocks the data bit stream into the flash media card using the baud rate as a reference clock.

Abstract: A controller for a DC to DC converter. The controller may comprise linear mode circuitry and switch mode control circuitry. The linear mode control circuitry may be capable of providing a first control signal to a controlled device of the DC to DC converter. The controlled device may operate as a variable resistor in response to the first control signal to control an output voltage of the DC to DC converter. The switch mode control circuitry may be capable of providing a second control signal to the controlled device of the DC to DC converter. The controlled device may turn ON and OFF in response to the second control signal to control the output voltage of the DC to DC converter. One of the linear mode control circuitry and the switch mode control circuitry may be enabled. The controller may also include protection circuitry.

Abstract: A computer system having entertainment mode capabilities is provided. In an exemplary embodiment, the system may include an entertainment mode power switch. A machine-readable medium may be provided that includes instruction stored thereon that may perform operations including enabling entertainment mode user account data to be stored on the computer system. Further operations may include passing the entertainment mode user account data to an operating system logon process associated with the computer system when the entertainment mode power switch is activated to power the computer system. In at least one exemplary embodiment, the entertainment mode user account data is passed automatically to the operating system during a logon process.

Abstract: A selector circuit configured to select among a DC power source and a plurality of batteries for an electronic device. The selector circuit includes a first comparator configured to compare a first input signal representative of a voltage level of the DC power source with a first threshold level and provide a first output signal representative of a difference between the first input signal and the first threshold level, and a selector output circuit. The selector output circuit is configured to provide selector output signals that control selection among the DC power source and the plurality of batteries. The selector output circuit providing said selector output signals to select the DC source and deselect the plurality of batteries if the first output signal is representative of the voltage level of said DC power source being greater than the first threshold level.

Abstract: A charging circuit for controlling a system charging parameter provided to a host of rechargeable batteries, wherein the host of batteries includes at least a first battery and second battery that may be coupled in parallel. The charging circuit provides for fast charging of rechargeable batteries in parallel. Independent current and voltage sensing for each battery enables parallel charging of batteries at different charging currents. The charging circuit may be configured to accept either analog or digital signals from an associated power management unit.

Abstract: A programmable after-package, on-chip reference voltage trim circuit for an integrated circuit having a plurality of programmable trim cells generating a programmed sequence. A converter is provided to convert the bit sequence into a trim current. The trim current is added to an initial value of a reference voltage to be trimmed, as generated by the integrated circuit. Once the correct value of the trim current is determined, isolation circuitry is programmed to isolate the trim circuitry from the remainder of the IC, thereby freeing the logic and package pins associated with the IC for use by users of the IC. The preferred trim circuitry includes fuses which are blown in accordance with a bit value supplied to the trim cell to permanently fix a trim current value, once a best fit value is determined.

Abstract: A sequential burst mode regulation system to deliver power to a plurality of loads. In the exemplary embodiments, the system of the present invention generates a plurality of phased pulse width modulated signals from a single pulse width modulated signal, where each of the phased signals regulates power to a respective load. Exemplary circuitry includes a PWM signal generator, and a phase delay array that receives a PWM signal and generates a plurality of phased PWM signals which are used to regulate power to respective loads. A frequency selector circuit can be provided that sets the frequency of the PWM signal using a fixed or variable frequency reference signal.

Abstract: A DC to DC converter having improved transient response, accuracy, and stability. The DC to DC converter includes a comparator configured to compare a reference signal with a second signal. The reference signal has a DC offset determined, at least in part, by a DC reference voltage source. The second signal is representative of an output voltage of the DC to DC converter. The comparator is further configured to provide a control signal to a driver that drives the output voltage of the DC to DC converter in response to a comparison of the reference and second signal. The DC to DC converter further includes an accuracy circuit to enhance accuracy of the DC to DC converter. The DC to DC converter may further include a stability circuit to enhance stability of the DC to DC converter.