Patents Assigned to iWatt, Inc.
  • Publication number: 20140022829
    Abstract: The embodiments disclosed herein describe a method of a controller of a switching power converter that provides a configurable power factor control method for the switching power converter. In one embodiment, the controller combines power regulation control methods of constant on-time control and constant power control to adjust the power factor of the switching power converter.
    Type: Application
    Filed: July 18, 2012
    Publication date: January 23, 2014
    Applicant: IWATT, INC.
    Inventors: Fuqiang Shi, Xiaolin Gao, Hien Huu Bui, Yong Li, John William Kesterson
  • Publication number: 20130241430
    Abstract: The embodiments disclosed herein describe the dynamic control of a switching power converter between different operation modes of the switching power converter. In one embodiment, the operation modes of the switching power converter include a switching mode and a linear mode. The switching power converter may be included in a LED lamp system according to one embodiment.
    Type: Application
    Filed: March 13, 2012
    Publication date: September 19, 2013
    Applicant: IWATT, INC.
    Inventors: Andrew Kwok-Cheung Lee, Chuanyang Wang, Jiang Chen, Liang Yan
  • Publication number: 20130107584
    Abstract: The embodiments herein describe a dynamic metal-oxide-semiconductor field-effect transistor (MOSFET) gate driver system architecture and control scheme. The MOSFET gate driver system dynamically adjusts both the gate driver turn-on-resistance and the gate driver turn-off resistance within a single (i.e., one) switching cycle to reduce electromagnetic interference (EMI) in the system and to minimize the conduction loss of a power MOSFET during operation.
    Type: Application
    Filed: August 7, 2012
    Publication date: May 2, 2013
    Applicant: IWATT, INC.
    Inventors: Yong Li, Fuqiang Shi, Andrew Kwok-Cheung Lee, David Nguyen, Jiang Chen
  • Patent number: 8184762
    Abstract: A digital phase lock loop circuit provides an output with reduced jitter. The digital phase lock loop circuit includes a phase frequency detector that determines a phase difference between a feedback signal and a reference frequency signal to generate an error signal indicative of the phase difference. A numerically controlled oscillator generates a first oscillator output signal with a frequency proportional to the error signal and a second oscillator output signal indicative of jitter of the first oscillator output signal in reference to the reference frequency signal. A phase accuracy extender determines a delay amount from the second oscillator output signal and delays the first oscillator output signal by the delay amount to generate a phase-enhanced output signal with edges aligned with one of a plurality of reference clock signals.
    Type: Grant
    Filed: November 6, 2008
    Date of Patent: May 22, 2012
    Assignee: iWatt, Inc.
    Inventors: John W. Kesterson, Carrie Seim, Selcuk Sen, Xuecheng Jin
  • Patent number: 6972969
    Abstract: A primary side sensing power control system and method that controls the current limit such that it is maintained within a small range for any acceptable input voltages and causes the output voltage of a PWM controller to drop as the output load increases when the current limit is reached.
    Type: Grant
    Filed: August 19, 2004
    Date of Patent: December 6, 2005
    Assignee: iWatt, Inc.
    Inventors: Anatoly Shteynberg, Junjie Zheng, Harry Rodriguez, Mark D. Telefus, Dongsheng Zhou
  • Patent number: 6900995
    Abstract: A method of regulating voltage at an output of a switching power converter includes sensing an output voltage feedback signal; comparing the sensed feedback signal to a reference at a determined time during a cycling of the switch; and regulating the output voltage by either enabling or inhibiting cycling of a switch by a cycle of a drive signal produced by pulse generation circuitry in response to an output of the comparison.
    Type: Grant
    Filed: November 27, 2002
    Date of Patent: May 31, 2005
    Assignee: iWatt, Inc.
    Inventors: Mark R. Muegge, Mark Eason, Mark D. Telefus
  • Patent number: 6894911
    Abstract: A method of regulating voltage at an output of a switching power converter, the converter comprising a switch and pulse generation circuitry, the pulse generation circuitry producing one or more drive signals for cycling the switch ON and OFF, wherein if the switch is cycled ON and OFF according to a cycle of a drive signal, power is transferred from a source to a load. The method includes sensing an output voltage feedback signal, comparing the sensed feedback signal to a reference at a determined time during a cycling of the switch, and regulating an output voltage at the load by controlling whether a cycle of one of the drive signals cycles the switch in response to the comparison.
    Type: Grant
    Filed: November 27, 2002
    Date of Patent: May 17, 2005
    Assignee: iWatt, Inc.
    Inventors: Mark D. Telefus, Mark R. Muegge, Charles R. Geber, Dickson T. Wong
  • Patent number: 6882552
    Abstract: A power converter for delivering power from a source to a load includes a switch, pulse generation circuitry producing one or more drive signals for cycling the switch ON and OFF, wherein if the switch is cycled ON and OFF according to a cycle of a drive signal, power is transferred from the source to the load, a comparator for comparing a feedback signal approximating an output voltage at the load to a reference, and a controller coupled to the pulse generation circuitry for controlling which, if any, cycle of a drive signal cycles the switch in response to an output of the comparator.
    Type: Grant
    Filed: November 27, 2002
    Date of Patent: April 19, 2005
    Assignee: iWatt, Inc.
    Inventors: Mark D. Telefus, Mark R. Muegge, Charles R. Geber, Dickson T. Wong
  • Patent number: 6862198
    Abstract: Switching power converters for regulating voltage at an output of a load include digital control circuitry for sensing an output voltage feedback signal, comparing the sensed feedback signal to a reference at a determined time during a cycling of the switch; and regulating the output voltage by either enabling or inhibiting cycling of a switch by a cycle of a drive signal produced by pulse generation circuitry in response to the comparison.
    Type: Grant
    Filed: November 27, 2002
    Date of Patent: March 1, 2005
    Assignee: iWatt, Inc.
    Inventors: Mark R. Muegge, Mark Eason, Mark D. Telefus
  • Patent number: 6765774
    Abstract: A high-impedance-insertion system suppresses load-produced electromagnetic noise from interfering into a power source by coupling the load to the power source through a switch. If the power source is an AC power source, the switch couples to the power source through a storage element and a rectifier, such that the switch is OFF (in the high impedance state) when the rectifier is reversed biased (or in a low impedance state). If the power source is a DC power source, the switch couples to the power source through a storage element and a second switch, such that the switch is OFF (in the high impedance state) when the second switch is ON (in the low impedance state).
    Type: Grant
    Filed: May 31, 2002
    Date of Patent: July 20, 2004
    Assignee: iWatt, Inc.
    Inventors: Mark D. Telefus, Anatoly Shteynberg
  • Patent number: 6621255
    Abstract: A power supply having a plurality of switches coupled in parallel between an input and an output regulates the output voltage by altering the number of conducting switches in response to power demands at the output.
    Type: Grant
    Filed: January 15, 2002
    Date of Patent: September 16, 2003
    Assignee: iWatt, Inc.
    Inventor: Mark D. Telefus
  • Patent number: 6385059
    Abstract: Control circuitry for controlling the delivery of power from a source voltage to a load in a transformer coupled power converter. The control circuitry includes a power switch having an input coupled to the source, an output, and an activation gate, the power switch, when cycled ON and OFF, defining a pulses of power at the load. A pulse generator is coupled to the power switch, the pulse generator producing a train of constant frequency, constant ON time switching pulses for driving the power switch activation gate. A pulse rate controller responsive to an error signal is coupled between the pulse generator and the power switch, the pulse rate controller regulating an output voltage at the load by controlling the rate of switching pulses delivered to the power switch activation gate over time. The error signal is derived by estimating the output voltage at each switching cycle from the primary side current, while compensating for the expected loss between the source and the load for each power switch cycle.
    Type: Grant
    Filed: November 14, 2000
    Date of Patent: May 7, 2002
    Assignee: Iwatt, Inc.
    Inventors: Mark D. Telefus, Mark R. Muegge