1
James H Nguyen, Thomas T Chiang, Christopher T Falvey: Constant-peak-current minimum-off-time pulse frequency modulator for switching regulators. Monolithic Power Systems, Perkins Coie, October 3, 2006: US07116089 (24 worldwide citation)

Methods and apparatus are disclosed for controlling switching regulators to automatically switch from a traditional pulse-width modulation (PWM) mode, when the load current is higher than a predetermined value, to a pulse-frequency modulation (PFM) mode, when the load current drops to a point lower ...


2
James H Nguyen: Soft start system and method for switching regulator. Monolithic Power Systems, Perkins Coie, Zhou Lu, April 24, 2007: US07208927 (23 worldwide citation)

The present invention introduces methods and circuits to provide a soft start for a switching regulator. A feedback voltage from output terminal is monitored and used to regulate the bias current of the regulator's error amplifier. The present invention also enables a smooth transition from the soft ...


3
Giao M Pham, Barry J Concklin, James H Nguyen: Commutation delay generator for a multiphase brushless DC motor. Siliconix Incorporated, David E Steuber, Skjerven Morrill MacPherson Franklin & Friel, June 16, 1998: US05767643 (19 worldwide citation)

A commutation control circuit provides a substantially periodic series of commutation signals to a conventional motor sequencer. The control circuit includes a frequency-to-current converter that receives the series of commutation signals and outputs a current that has a magnitude proportional to th ...


4
James H Nguyen: Method and apparatus for synchronous buck with active negative current modulation. Monolithic Power Systems, Perkins Coie, July 17, 2012: US08222879 (9 worldwide citation)

A circuit is disclosed that includes a buck voltage regulator electrically coupled to an active current modulator. The active current modulator is operable to detect a negative current in the low-side switch of the buck voltage regulator circuit during a light mode operation. Whenever the negative c ...


5
James H Nguyen, Thomas T Chiang, Christopher T Falvey: Constant-peak-current minimum-off-time pulse frequency modulator for switching regulators. Monolithic Power Systems, Perkins Coie, Zhou Lu, October 21, 2008: US07439720 (8 worldwide citation)

Methods and apparatus are disclosed for controlling switching regulators to automatically switch from a traditional pulse-width modulation (PWM) mode, when the load current is higher than a predetermined value, to a pulse-frequency modulation (PFM) mode, when the load current drops to a point lower ...


6
James H Nguyen: Method and apparatus for synchronous buck with active negative current modulation. Monolithic Power Systems, Perkins Coie, April 19, 2011: US07928713 (7 worldwide citation)

A circuit is disclosed that includes a buck voltage regulator electrically coupled to an active current modulator. The active current modulator is operable to detect a negative current in the low-side switch of the buck voltage regulator circuit during a light mode operation. Whenever the negative c ...


7
Giao M Pham, James H Nguyen: Quiet commutation circuit for an electric motor. Siliconix incorporated, David E Steuber, Skjerven Morrill MacPherson Franklin & Friel, October 20, 1998: US05825145 (6 worldwide citation)

A commutation control circuit for a conventional brushless DC motor. The circuit reduces power supply noise normally induced when current is switched from one pair of motor windings to the next. The motor conventionally includes a number of windings, each of which includes a terminal connected to a ...


8
James H Nguyen: Power converter integrated circuit floor plan and package. Monolithic Power Systems, Perkins Coie, May 1, 2012: US08169088 (4 worldwide citation)

For a DC to DC converter circuit integrated on a packaged die, the relative positions of various die pads and power MOSFETs on the die for a small outline integrated circuit package are described.


9
James H Nguyen: Method and apparatus for synchronous boost voltage regulators with active negative current modulation. Monolithic Power Systems, Perkins Coie, February 22, 2011: US07893677 (3 worldwide citation)

A switch-mode synchronous boost voltage regulator is disclosed that includes a boost voltage regulator and an active current modulator. The active current modulator detects a negative current flowing through the high-side switch during a light load condition. When the negative current is detected, t ...


10
James H Nguyen, Francis C Yu: Current detection and emulation circuit, and method thereof. Monolithic Power Systems, Perkins Coie, November 10, 2015: US09184651 (3 worldwide citation)

A current detection circuit for detecting a current in a SMPS which has a first switch and a second switch; a current sensing circuit sensing a second switch current flowing through the second switch and providing a current sensing signal; and a current emulation circuit which generates a first curr ...