Off-line converter with digital control
Granted: July 24, 2007
Patent Number:
7248029
A DC to DC converter comprising an energy storage element comprising an energy storage element input and an energy storage element output, the energy storage element input coupled to receive a first power level and the energy storage element output providing a second power level. The converter also comprises a feedback circuit comprising a feedback input and a feedback output, the feedback input coupled to the energy storage element output. The converter further comprises a regulator…
Method and apparatus for conditional response to a fault condition in a switching power supply
Granted: July 17, 2007
Patent Number:
7245510
Techniques are disclosed to regulate an output of a power converter. One example power converter includes an energy transfer element coupled between an input and an output of the power converter. A switch included in the power converter is coupled to the input of the energy transfer element. The power converter also includes a controller circuit coupled to the switch. The controller circuit is also coupled to receive a feedback signal representative of the output of the power converter…
Method and apparatus to provide temporary peak power from a switching regulator
Granted: July 3, 2007
Patent Number:
7239119
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 substantially reducing electrical earth displacement current flow generated by wound components
Granted: June 26, 2007
Patent Number:
7236078
A method of transferring energy is disclosed. In one aspect, a method includes transferring energy from a first winding wound around a transformer core to a second winding wound around the transformer core. The first and second windings capacitively coupled to electrical earth. The method further includes generating a third winding electrostatic field with a third winding wound around the transformer core and coupled to the first winding. A fourth winding electrostatic field is generated…
Method and apparatus providing final test and trimming for a power supply controller
Granted: June 5, 2007
Patent Number:
7227733
A power supply controller having final test and trim circuitry. In one embodiment, a power supply controller for switched mode power supply includes a selector circuit, a trim circuit, a shutdown circuit and a disable circuit. The trim circuit includes a programmable circuit connection that can be selected by the selector circuit by toggling a voltage on an external terminal such as for example a power supply terminal, a control terminal or a function terminal of the power supply…
Method of manufacturing an integrated circuit with multilength power transistor elements
Granted: May 22, 2007
Patent Number:
7220629
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…
High-voltage vertical transistor with a multi-gradient drain doping profile
Granted: May 22, 2007
Patent Number:
7221011
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 fault condition protection of a switched mode power supply
Granted: May 15, 2007
Patent Number:
7218495
Methods and apparatuses for fault condition protection of a switched mode power supply. In one aspect of the invention, a power supply circuit having an auto-restart function to turn the power supply on and off repeatedly under fault conditions is included. In one embodiment, one or more off-times following detection of a fault condition is smaller than subsequent off-times.
Method and apparatus for maintaining a constant load current with line voltage in a switch mode power supply
Granted: May 8, 2007
Patent Number:
7215105
A power supply including a regulation circuit that maintains an approximately constant load current with line voltage. An example circuit includes a switch including first, second and third terminals. The first terminal is coupled or decoupled to the second terminal in response to a control signal received at the third terminal. Voltage sense circuitry is included and is coupled to sense a voltage drop across the switch. The voltage drop is representative of a current in the switch…
Method and apparatus to limit output power in a switching power supply
Granted: May 8, 2007
Patent Number:
7215107
Techniques are disclosed to adjust a current limit in a switching regulator. One example switching regulator includes a switch to be coupled to an energy transfer element of a power supply. A controller to generate a drive signal is coupled to control switching of the switch to regulate an output of the power supply. A current limiter is included in the controller to adjust the drive signal to limit a current though the switch to a variable current limit value. The variable current limit…
Method and apparatus for reducing audio noise in a switching regulator
Granted: May 1, 2007
Patent Number:
7211991
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 robust mode selection with low power consumption
Granted: May 1, 2007
Patent Number:
7212058
A low power method and apparatus for selecting operational modes of a circuit. One circuit according to the teachings of the disclosed method and apparatus includes a first current limiting circuit coupled between a selector terminal and a first voltage bus. The first current limiting circuit is adapted to vary a current limit out of the selector terminal in response to a voltage on the selector terminal. The circuit also includes a second current limiting circuit coupled between the…
Method and apparatus for extending the operating range of a flyforward converter
Granted: April 24, 2007
Patent Number:
7209371
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 first 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 a switch mode power supply that generates a high pulse width modulation gain while maintaining low noise sensitivity
Granted: April 17, 2007
Patent Number:
7205754
A power supply with high pulse width modulation gain and low noise sensitivity has been disclosed. In one example, a control current is received at a control terminal of a regulator circuit. The control current includes a consumption current of the regulator circuit and a feedback current. A duty cycle at which a power switch is switched is adjusted in response to the feedback current. The consumption current of the regulator circuit is increased during an on-time of the power switch in…
Method and apparatus for controlling a circuit with a high voltage sense device
Granted: April 17, 2007
Patent Number:
7205824
A control circuit with a high voltage sense device. In one embodiment, an apparatus includes a first transistor disposed in a substrate having a first, a second and a third terminal. The first terminal of the first transistor is to be coupled to an external voltage and the second and third terminals of the first transistor are to be coupled to a ground reference voltage. The apparatus also includes a second transistor disposed in the substrate having a first, a second and a tap terminal.…
Method and apparatus for transferring energy in a power converter circuit
Granted: April 17, 2007
Patent Number:
7205877
A reduced cost energy transfer element for power converter circuits. In one embodiment, an energy transfer element according to an embodiment of the present invention includes a magnetic element having an external surface with at least a first winding and a second winding wound around the external surface of the magnetic element without a bobbin. As such, energy to be received from a power converter circuit input is to be transferred from the first winding to the second winding through a…
Switched mode power supply responsive to current derived from voltage across energy transfer element input
Granted: March 20, 2007
Patent Number:
7193865
A switched mode power supply having a regulated reflected voltage. In one circuit, a power switch is coupled between first and second electrical terminals. An energy transfer element is coupled to the first electrical terminal of the power switch. A power supply rail is coupled to the second electrical terminal. A control circuit is coupled to the energy transfer element and to the power switch. The control circuit is to switch the power switch in response to a signal derived from a…
Method and apparatus for dissipative clamping of an electrical circuit
Granted: March 20, 2007
Patent Number:
7193870
Dissipative clamping apparatuses and methods for electrical circuits. In one aspect of the invention, In one aspect of the invention, a method includes switching a power supply input on an energy transfer element, regulating a power supply output by switching the power supply input on the energy transfer element, clamping a voltage on the energy transfer element to a clamp voltage and varying the clamp voltage in response to the power supply input. In another aspect, an electrical…
Method and apparatus for sensing current and voltage in circuits with voltage across an LED
Granted: March 13, 2007
Patent Number:
7190215
Methods and apparatuses to sense current and voltage in circuits with voltage drop. In one aspect of the invention, a sense circuit includes a first diode, a first resistor and a light emitting diode (LED). The first resistor is coupled to the first diode. The first current is to be directed through the first diode and the first resistor. A first voltage being the sum of the voltages is developed across the first resistor and the first diode. The LED is coupled to the first diode and the…
Method and apparatus to reduce maximum power from a power supply with transition region regulation
Granted: February 20, 2007
Patent Number:
7180280
Techniques are disclosed to regulate the output power of a power supply. An example power supply regulator includes an energy transfer element coupled between an input and an output of a switched mode power supply. A switch is coupled to the energy transfer element at the input of the power supply. A controller is coupled to the switch to control switching of the switch to regulate the output of the switched mode power supply in response to a feedback signal. A feedback circuit is…
