Patents Assigned to Zilker Labs, Inc.
  • Patent number: 7467309
    Abstract: A new system-level approach to managing the delivery of DC voltage and current. Several system level functions may be enabled without requiring separate ICs to perform those functions. Supervisory functions for a voltage converter may be performed by a central control module or chip that may be coupled to point-of-load voltage converters comprised in digital power management devices (DPMD) through a serial digital bus. The DPMDs may also use the high-speed serial digital bus to provide real-time feedback information to the central control module or chip. Single DPMDs may be combined together in a current sharing configuration in a “plug-and-play” fashion, where the control logic in each DPMD is capable of automatically establishing control loops required a multi-phase supply. Feedback necessary for establishing control may be transmitted across the digital bus coupling the devices.
    Type: Grant
    Filed: February 17, 2006
    Date of Patent: December 16, 2008
    Assignee: Zilker Labs, Inc.
    Inventor: James W. Templeton
  • Patent number: 7327130
    Abstract: A current-sense circuit for measuring a load current in a switching power regulator may operate independently of process variation and temperature, and measure bi-directional load currents without requiring high-speed, high-voltage amplifiers for operation. A positive sense voltage may be generated for positive and/or negative values of a switch current conducted by a power switching device in the switching power regulator, by applying a linear transformation to a switch voltage developed across the power switching device according to the switch current. A first sense current may be generated by applying the positive sense voltage across a matching switching device having a same channel length as the power switching device. A second sense current may be generated independently of the switch voltage, and a total sense current that is proportional to the switch current may be calculated by subtracting the second current from the first current.
    Type: Grant
    Filed: June 21, 2006
    Date of Patent: February 5, 2008
    Assignee: Zilker Labs, Inc.
    Inventor: Demetri Giannopoulos
  • Patent number: 7292019
    Abstract: The control precision of one or more parameters of an integrated circuit (IC), for example the output voltage of a voltage regulator comprised in the IC, may be improved even when using inaccurate components external to the IC. Control of the output voltage, or any parameter, using components external to the IC may include coupling a resistor to the IC and measuring the actual resistance value of the resistor, and based on the measured value, selecting a nominal resistance value from a set of resistance values previously specified by the user. The output voltage, or parameter, may be generated according to the nominal resistance value instead of the actual resistance value, thereby reducing the error that may be incurred due the actual resistance value of the resistor not matching the expected nominal value of the resistor.
    Type: Grant
    Filed: February 24, 2006
    Date of Patent: November 6, 2007
    Assignee: Zilker Labs, Inc.
    Inventor: Kenneth W. Fernald
  • Patent number: 7239257
    Abstract: A power converter including a hardware efficient control loop architecture. Error detection circuitry may generate an error signal based on the difference between a power converter output voltage and a reference voltage. An oversampling ADC may digitize the error signal. The transfer function associated with the ADC may include quantization levels spaced at non-uniform intervals away from a center code. A digital filter may calculate the average of the digitized error signal. A nonlinear requantizer may reduce the number of codes corresponding to the output of the digital filter. A proportional integral derivative (PID) unit may multiply the output of the nonlinear requantizer by PID coefficients to generate a PID duty cycle command, and a gain compensation unit may dynamically adjust the PID coefficients to maintain a constant control loop gain. A noise-shaped truncation unit including a multi-level error-feedback delta sigma modulator may reduce the resolution of the PID duty cycle command.
    Type: Grant
    Filed: March 16, 2006
    Date of Patent: July 3, 2007
    Assignee: Zilker Labs, Inc.
    Inventors: Mark A. Alexander, Douglas E. Heineman, Kenneth W. Fernald, Scott K. Herrington