Power Integrations Patent Grants

Gate metal routing for transistor with checkerboarded layout

Granted: December 23, 2008
Patent Number: 7468536
In one embodiment, a transistor fabricated on a semiconductor die is arranged into sections of elongated transistor segments. The sections are arranged in rows and columns substantially across the semiconductor die. Adjacent sections in a row or a column are oriented such that the length of the transistor segments in a first one of the adjacent sections extends in a first direction, and the length of the transistor segments in a second one of the adjacent sections extends in a second…

Method and apparatus for simplifying the control of a switch

Granted: December 16, 2008
Patent Number: 7466170
A technique for simplifying the control of a switch is presented. In one embodiment, a method of controlling a switch as a function of the voltage across the switch is presented. In one embodiment a method of controlling a switch as a function of the slope of the voltage across the switch is present. In one embodiment a switching is switched on for an on time period that is substantially fixed in response to a voltage across the switch while the switch is off. In one embodiment a switch…

High-voltage vertical transistor with a multi-gradient drain doping profile

Granted: December 2, 2008
Patent Number: 7459366
A high-voltage transistor includes first and second trenches that define a mesa in a semiconductor substrate. First and second field plate members are respectively disposed in the first and second trenches, with each of the first and second field plate members being separated from the mesa by a dielectric layer. The mesa includes a plurality of sections, each section having a substantially constant doping concentration gradient, the gradient of one section being at least 10% greater than…

Method and apparatus for increasing the power capability of a power supply

Granted: November 18, 2008
Patent Number: 7453709
Techniques are disclosed to extend an on time period of switch to regulate a transfer of energy from an input of a power supply to an output of a power supply. One example integrated circuit includes an energy transfer element coupled between an input and an output of the power supply. A switch is coupled to the input of the energy transfer element. A controller is coupled to the switch to control switching of the switch to regulate a transfer of energy from the input of the power supply…

Transformerless safety isolation in a power supply using safety capacitors for galvanic isolation

Granted: November 18, 2008
Patent Number: 7453710
An apparatus and method are disclosed to provide transformerless safety isolation in a power supply. One example regulated power converter includes input terminals included in a primary circuit of the power converter. Output terminals are included in a secondary circuit of the power converter. A plurality of safety capacitors including first and second safety capacitors are also included. Each of the plurality of safety capacitors includes a respective first terminal coupled to the…

Fault condition protection

Granted: November 4, 2008
Patent Number: 7446988
A circuit protects a power conversion system with a feedback control loop from a fault condition. The circuit has an oscillator having an input for generating a signal with a frequency and a timer connected to the oscillator input and to the feedback control loop. The timer disables the oscillator after a period following the opening of the feedback control loop to protect the power conversion system.

Method and apparatus for a voltage triggered current sink circuit

Granted: October 28, 2008
Patent Number: 7443153
A current sink circuit is disclosed. An apparatus according to aspects of the present invention includes a sensing element, a pass element coupled to the sensing element and a setting element coupled to the pass element. The setting element provides both a voltage threshold level and a current regulation reference. The pass element is to pass current conducted through the current sink circuit in response to the setting element. The current conducted through the current sink circuit is…

Method and apparatus to select a parameter/mode based on a time measurement

Granted: September 16, 2008
Patent Number: 7425834
Techniques are disclosed to select functional parameters and/or operating modes of a circuit based on a time measurement are disclosed. One example integrated circuit includes a threshold detection and timing circuit that is coupled to measure a signal during an initialization period of the integrated circuit from a multifunction capacitor that is to be coupled to a first terminal of the integrated circuit. A selection circuit is coupled to the threshold detection and timing circuit to…

Method and apparatus for conditional response to a fault condition in a switching power supply

Granted: July 29, 2008
Patent Number: 7405954
Techniques are disclosed to regulate an output of a power converter. One example power converter controller circuit includes a line sense input to be coupled to receive a signal representative of an input voltage of a power converter. A feedback input is included and is to be coupled to receive a feedback signal representative of an output of the power converter. A drive signal generator is included and is to generate a drive signal coupled to control switching of a switch to provide a…

Method and apparatus for extending the operating range of a flyforward converter

Granted: July 22, 2008
Patent Number: 7403402
A technique for extending the operating range of a flyforward converter to low input voltages. In one aspect, power converter includes a positive input supply rail and a negative input supply rail. A power converter input voltage is to be applied between the positive and negative input supply rails. A flyback energy transfer element having a flyback input winding and a forward energy transfer element having a forward input winding are also included. The flyback and forward input windings…

Method and apparatus for reducing audio noise in a switching regulator

Granted: July 15, 2008
Patent Number: 7400122
A switching regulator utilizing on/off control that reduces audio noise at light loads by adjusting the current limit of the switching regulator. In one embodiment, a switching regulator includes a state machine that adjusts the current limit of the switching regulator based on a pattern of feedback signal values from the output of the power supply for a preceding N cycles of the drive signal. The state machine adjusts the current limit lower at light loads such that cycles are not…

Method and apparatus for adjusting a reference

Granted: July 8, 2008
Patent Number: 7397231
Examples of a method and apparatus for adjusting a reference. One circuit includes a current divider to divide a current from a current source into a first current and a reference current. The circuit also includes a current mirror coupled to the current divider to receive the first current from the current divider and to receive an adjustment current. The adjustment current is to set the reference current such that the reference current is adjustable between a full value and a fraction…

Method and apparatus for balancing active capacitor leakage current

Granted: July 8, 2008
Patent Number: 7397680
A circuit that provides a method and apparatus to actively balance capacitor leakage current from series stacked capacitors and disconnects itself when stacked capacitors are configured for doubler operation. In one embodiment, the active circuit includes high voltage low current transistors, such as for example a PNP bipolar transistor and an NPN bipolar transistor, that are configured in a sink-source voltage follower arrangement with the bases of the transistors connected to a voltage…

Integrated circuit with multi-length output transistor segments

Granted: June 24, 2008
Patent Number: 7391088
A monolithic integrated circuit fabricated on a semiconductor die includes a control circuit and a first output transistor having segments substantially equal to a first length. A second output transistor has segments substantially equal to a second length. The first and second output transistors occupy an L-shaped area of the semiconductor die, the L-shaped area having first and second inner sides that are respectively disposed adjacent first and second sides of the control circuit. At…

Method and apparatus to provide temporary peak power from a switching regulator

Granted: June 17, 2008
Patent Number: 7388360
Various techniques directed to providing temporary peak power from a switching regulator are disclosed. In one aspect, a switching regulator includes a switch that is to be coupled between a power supply input and an energy transfer element of the power supply. A controller is coupled to be responsive to a feedback signal to be received from an output of the power supply. The controller is coupled to switch the switch in response to the feedback signal to regulate the output of the power…

Method and apparatus for mode selection for high voltage integrated circuits

Granted: June 10, 2008
Patent Number: 7385312
A method is disclosed to add functionality to a terminal of a high voltage integrated circuit without the penalty of additional high voltage circuitry. The benefit is that alternative modes of operation can be selected for testing, trimming parameters of the integrated circuit, or any other purpose without the cost of an additional terminal. In one embodiment, ordinary low voltage circuitry monitors the voltage on the terminal that normally is exposed to high voltage. The configuration…

Gate etch process for a high-voltage FET

Granted: June 3, 2008
Patent Number: 7381618
A method, in one embodiment, includes etching first and second dielectric regions in a substantially isotropic manner through first and second openings of a mask layer to create first and second trenches. The first and second dielectric regions are disposed on opposite sides of a mesa of semiconductor material, the mesa having first and second sidewalls that respectively adjoin the first and second dielectric regions. The first and second dielectric regions in the first and second…

Method and apparatus for substantially reducing electrical displacement current flow between input and output circuits coupled to input and output windings of an energy transfer element

Granted: May 27, 2008
Patent Number: 7378929
An energy transfer element with substantially reduced electrical displacement current flow between an input circuit coupled to the energy transfer element input winding and an output circuit coupled to the energy transfer element output winding. In one aspect, an energy transfer element includes an input winding, an output winding, an electrically conductive shield coupled to the input winding and a first cancellation winding coupled to the input winding. The electrically conductive…

Method and article of manufacture for designing a transformer

Granted: May 20, 2008
Patent Number: 7373714
Various techniques directed to the design and construction of transformers are disclosed. In one aspect, a method according to embodiments of the present invention includes loading parameters of a transformer included in a power supply design, calculating primary winding parameters of the transformer in response to the loaded parameters of the transformer, calculating secondary winding parameters of the transformer in response to the loaded parameters of the transformer. Shield winding…

Method for reducing the cost of voltage regulation circuitry in switch mode power supplies

Granted: May 6, 2008
Patent Number: 7368894
A reduced cost voltage regulation circuit for switched mode power supplies. In one example, a current sense circuit includes a current sense terminal of a voltage regulation circuit. A voltage difference between the current sense terminal and a voltage reference terminal of the voltage regulation circuit is substantially fixed when a first current to be sensed by the current sense circuit at the current sense terminal is substantially equal to a first current sense threshold. A power…