Atmel Corporation

At&t Intellectual Property I, L.p.

National Semiconductor Corporation

Sbc Knowledge Ventures, L.p.

Sean S Chen

Zesen Chen

Peter Chou

Brian Gonsalves

Yongdong Zhao

Dilip Sangam

Hong Zhang

Wenbo Liang

Jeff Kotowski

Hendrik Santo

Donald M Smith

Shih-Chung Tom Soon

Timothy James Herklots

Wenge Chen

Robert A Pease

Stuart B Shacter

Yongliang Wang

Tushar Heramb Dhayagude

Minjong Kim

Balaji Venugopal Virajpet

Holly Chen

Sivaprakash Kannan

Klen Vi

Liwei Liu

Methods, systems, and apparatus, including computer programs encoded on computer storage media, for fault detection in a power control system. In one aspect, a method includes measuring a plurality of values of a feedback voltage from a power control system over a period of time; determining a rate of feedback voltage change based on the measured values of the feedback voltage and a duration of the period of time; determining, with a controller, that the determined rate of feedback voltage change is smaller than a threshold rate of change; and in response to determining that the determined rate of feedback voltage change is smaller than the threshold rate of change, transmitting a fault indication signal to the power control system.

Fault detection

A circuit for driving light emitting elements, such as LEDs, includes a first transistor having a source coupled to ground through a first resistive element, and a second transistor having a gate electrically coupled to a gate of the first transistor, a source electrically coupled to ground, and a drain for electrical connection to a first group of light emitting elements. The circuit also includes circuitry to provide a predetermined voltage at the source of the first transistor, circuitry to compensate for a difference in respective gate-source voltages of the first and second transistors, and circuitry to compensate for a difference in respective drain-source voltages of the first and second transistors. In some implementations, the circuit can achieve relatively low power consumption.

Driving circuits for light emitting elements

A controller circuit for the control of a power converter is disclosed. An example controller circuit generates a waveform that drives a switch that controls the power converter. The controller circuit includes a divider module that generates a modification factor based on a ratio of the two input signals of the module. The circuit includes a module that generates a first waveform configured for a critical conducting mode of operation of a power converter and an on-time adjuster module that modifies the first waveform based on the modification factor and generates a second waveform. The second waveform is delivered to the switch. An example modification factor is the ratio of the output voltage to the rectified input voltage of the power converter.

Low total harmonic distortion and high power factor correction power converters

A fault protection and correction circuit for the control of a power converter is disclosed. An example circuit generates a waveform that drives a switch on or off and controls the power converter. The controller circuit in addition to power factor correction (PFC) circuitry includes a first and a second shut down mode modules, both of them cause the switching to stop. The circuit includes a module for receiving fault events. When a fault occurs, the controller enters the second shut down mode. The controller stays in the second shut down mode if the required current for this mode can be provided by the outside circuitry. Otherwise, the controller enters the first shut down mode that requires less current and subsequently restarts the controller. By modifying the outside circuitry the controller can respond differently to fault events.

Fault protection and correction of line and load faults

An adaptive phase-lead compensation (zero) circuit is disclosed that can be added to a circuit (e.g., a CMOS-based LDO) to ease the compensation and increase the phase margin of the circuit. By using the disclosed adaptive phase-lead compensation circuit, an adjustable resistance can be connected to any nodes in the compensated circuit rather than just to the voltage source (VDD) or ground (GND), allowing the Miller Effect to be used via a Miller capacitor.

Adaptive phase-lead compensation with Miller Effect

A dual-mode circuit for the control of an AC/DC power converter is disclosed. An example dual-mode controller circuit generates a waveform that drives a switch on or off and controls the power converter. The controller circuit in addition to power factor correction (PFC) circuitry includes a critical conducting mode (CrM) module as well as a discontinuous conducting mode (DCM) module configured to generate waveforms adapted for CrM and DCM operation of a power converter. The circuit includes a node for receiving a feedback signal of a voltage or a current. Based on the received signal, one of the modules is selected at a time to supply the waveform at the output of the dual-mode controller. An example of the output waveform is a series of pulses that are configured to drive the switch that controls the transfer of power between input and output of the power converter.

Dual-mode, AC/DC power converter with power factor correction

Various embodiments of the disclosed subject matter provide methods and systems to store a policy specifying rules relating to recording, storage or delivery of broadcast programming to a consumer of such programming, and to record, store or deliver broadcast programming in response to a rule. According to an example embodiment, a method and system provide for a subscriber requesting that a broadcast television program be saved for the subscriber upstream from the subscriber in a television distribution system, and that the program offered to the subscriber for saving is determined based on a policy established for the program. According to another example embodiment a system provides a computing device including a computer program to control the recording or delivery of a broadcast television program in accordance with a policy established to control the recording or delivery of the broadcast television program.

System and method for recording and time-shifting programming in a television distribution system using policies

In one novel aspect, driving a string of light emitting elements, such as LEDs, includes applying a drive signal to circuitry that regulates a voltage appearing at a source of a transistor whose drain is coupled to one end of the string of light emitting elements and whose source is coupled to ground through a resistive element. Sequencing of the drive signal and a voltage supply signal for the light emitting elements is controlled such that the voltage supply signal is not increased above a predetermined allowable voltage for the transistor until the transistor is turned on, and such that the supply voltage is not decreased below the allowable voltage for the transistor until the transistor is turned off.

Circuit for driving light emitting elements

The disclosed multi-channel driver equalizer circuit matches currents in multiple strings of illumination devices at low current levels by using an analog equalizer to sequentially couple the output of a reference amplifier in series with each current source amplifier in a current limit loop of the driver equalizer circuit to correct the offsets of the current source amplifiers, resulting in the matching of string currents on average.

Multi-channel driver equalizer

Various embodiments of the disclosed subject matter provide methods and systems to store a policy specifying at least one rule relating to recording, storage or delivery of broadcast programming to a consumer of such programming, and to record, store or deliver broadcast programming in response to at least one of the rules in the policy. According to another example embodiment, a method and system provide for a subscriber requesting that at least one broadcast television program be saved for the subscriber upstream from the subscriber in a television distribution system, and further that the at least one program offered to the subscriber for saving is determined based on a policy established for the at least program. According to another example embodiment a system provides at least one computing device including a computer program to control the recording or delivery of at least one broadcast television program in accordance with a policy established to control the recording or delivery of the broadcast television program.

Various embodiments of the disclosed subject matter provide methods and systems to record broadcast programming for at least one television channel for a period of time, wherein the recording is performed upstream from subscribers in a television distribution system, and further including after the period of time, keeping recorded programming by request from at least one subscriber. And further wherein the request is for at least one television program contained in the recorded programming or for a time window for a particular channel. According to another embodiment a subscriber requests that broadcast programming be saved for the subscriber upstream from the subscriber in a television distribution system, and wherein the subscriber may request the programming be saved for later viewing by the subscriber between the time the programming was broadcast and a later point in time.

System and method for recording and time-shifting programming in a television distribution system with limited content retention

The innovation relates to systems and/or methodologies for error detection during sub-assembly in high voltage analog circuits. A signal driver communicates test signals to one or more high voltage analog circuits, and a state machine compares the electrical and/or thermal responses of the high voltage analog circuits to a set of predetermined expected results (e.g., signatures). The signal driver and state machine can be incorporated into the high voltage analog circuits. The expected results can be stored in the target circuits in the form of look-up tables, matrices, and so forth. Errors, such as, dry solders and bridge solders can be determined based on the comparison of the obtained responses to the expected signatures.

Method and apparatus for sub-assembly error detection in high voltage analog circuits and pins

The present invention discloses apparatus and techniques relating to the intelligent control of a display's backlight LED strings. The present invention provides for controlling the display intensity on a region-by-region basis and for adjusting the intensity multiple times within the duration of a frame. The present invention also provides backlight adjustment in a manner that emphasizes certain colors and deemphasizes certain colors. The present invention also provides for adjustment of the backlight based on the ambient temperature.

Growing community of inventors

Sunnyvale, CA, United States of America

Sean S Chen