Method and apparatus to control output power from a switching power supply
Granted: June 30, 2009
Patent Number:
7554826
Techniques are disclosed to control output power from a switching power supply. A sample power converter controller circuit includes a control circuit coupled to be coupled to a switch. The control circuit includes a current sense circuit to be coupled to a primary winding of an energy transfer element coupled to the switch. The control circuit also includes a measurement circuit to be coupled to a secondary winding of the energy transfer element. A feedback circuit is also included and…
Method and apparatus to provide temporary peak power from a switching regulator
Granted: May 26, 2009
Patent Number:
7538533
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 fault detection in a switching power supply
Granted: May 26, 2009
Patent Number:
7539028
Techniques are disclosed to detect a fault in the feedback circuit of a switching power supply while the power supply operates in a mode where the output is below its regulated value. The power supply delivers maximum power at a given switching frequency without a feedback signal while the output is below its regulated value. A fault protection circuit substantially reduces the average output power if there is no feedback signal for the duration of a fault time. When there is no feedback…
Method and apparatus for mode selection for high voltage integrated circuits
Granted: May 19, 2009
Patent Number:
7535130
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…
Method and apparatus for an in-rush current limiting circuit
Granted: May 19, 2009
Patent Number:
7535691
An in-rush current limiting circuit is disclosed. An apparatus according to aspects of the present invention includes a power switch having a first, second and third terminals. A capacitor having a first terminal and a second terminal is also included. The second terminal of the capacitor is coupled to the first terminal of a current source. The second terminal of the current source is coupled to a second input terminal of the in-rush current limit circuit. A power switch is also…
Compensation for parameter variations in a feedback circuit
Granted: May 19, 2009
Patent Number:
7535735
Techniques to compensate for parameter variations in a feedback circuit are disclosed. In one embodiment, a regulator circuit includes an energy source coupled to output a generated current in response to a control current. A feedback resistor is coupled to an output of the regulator circuit. The feedback resistor is coupled to conduct a feedback current responsive to the output of the regulator circuit. A current amplifier is coupled to the feedback resistor to generate the control…
Method and article of manufacturing for designing a transformer
Granted: April 21, 2009
Patent Number:
7520046
Various techniques directed to the design and construction of transformers are disclosed. In one aspect, a computer system according to embodiments of the present invention includes instructions stored on a storage media which when executed by a processor performs the operations of 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…
Method and apparatus for a control circuit with multiple operation modes
Granted: April 14, 2009
Patent Number:
7518885
An apparatus for regulating a power converter with multiple operating modes includes a switch coupled to an energy transfer element coupled between an input and an output of the power converter. A control circuit is also included, which is coupled to the switch to control the switch. The control circuit includes first and second duty cycle control modes to regulate power delivered to the output of the power converter. A transition between the first and second duty cycle control modes is…
Method and apparatus for conditional response to a fault condition in a switching power supply
Granted: April 14, 2009
Patent Number:
7518889
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 to be coupled to receive a feedback signal representative of an output of the power converter is also included. A drive signal generator is also included to generate a drive signal coupled to control switching of a switch to provide a…
Method and apparatus for output voltage regulation in primary control switched mode power supplies
Granted: April 7, 2009
Patent Number:
7515440
A voltage sense circuit and power supply regulation technique. In one aspect, a voltage sense circuit utilized in a power supply regulator includes a transformer including a sense winding and an output winding. A first diode is coupled to the sense winding, a first resistor is coupled to the first diode and a first capacitor coupled to the first resistor and the first diode. A second diode coupled to the first capacitor, the first resistor and the first diode. A second capacitor coupled…
Power supply controller responsive to a feedforward signal
Granted: March 10, 2009
Patent Number:
7502236
An apparatus and method of switching a switch of a power supply in response to an input voltage signal are disclosed. According to aspects of the present invention, a power supply controller includes a switch duty cycle controller coupled to receive a feedback signal and a duty cycle adjust signal. The switch duty cycle controller is coupled to generate a drive signal coupled to control switching of a switch, which is coupled to an energy transfer element, to regulate energy delivered…
Gate etch process for a high-voltage FET
Granted: February 24, 2009
Patent Number:
7494875
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 controlling a circuit with a high voltage sense device
Granted: February 17, 2009
Patent Number:
7491611
A control circuit with a high voltage sense device. In one embodiment, a circuit includes a first transistor disposed in a first substrate having first, second and third terminals. A first terminal of the first transistor is coupled to an external voltage. A voltage provided at a third terminal of the first transistor is substantially proportional to a voltage between the first and second terminals of the first transistor when the voltage between the first and second terminals of the…
Method and apparatus to improve frequency stability of an integrated circuit oscillator
Granted: February 17, 2009
Patent Number:
7492229
A simple low cost integrated circuit oscillator includes a capacitor coupled to be charged and discharged by first and second current sources. A first voltage follower circuit including a first bipolar transistor having a base is coupled to the capacitor. The first bipolar transistor is biased such that a voltage at an emitter of the first bipolar transistor follows a voltage on the capacitor. A first current path of a current mirror is coupled to the base of the first bipolar…
Method and apparatus for a high voltage power supply circuit
Granted: February 10, 2009
Patent Number:
7489120
A high voltage power supply method and apparatus is disclosed. An apparatus according to aspects of the present invention includes a power supply circuit having a rectifier circuit coupled to input terminals of the power supply circuit that are to be coupled to receive an AC input voltage. A switchmode power converter circuit is coupled to the rectifier circuit to receive a rectified input voltage to generate a regulated output voltage in response to the rectified input voltage. A switch…
Method and apparatus for fault condition protection of a switched mode power supply
Granted: February 10, 2009
Patent Number:
7489491
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 trimming current limit and frequency to maintain a constant maximum power
Granted: February 3, 2009
Patent Number:
7486062
A method which regulates a power supply. In one aspect of the invention, the method includes switching a power switch of a power supply regulator at an operating frequency (f) during operation of the power supply regulator. A current through the power switch is controlled to keep the current through the power switch below a peak current limit threshold (Ip) during operation of the power supply regulator. The maximum deliverable power value of a power supply to be regulated by the power…
Method and apparatus for transferring energy in a power converter circuit
Granted: January 27, 2009
Patent Number:
7482905
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…
Off-line converter with digital control
Granted: January 13, 2009
Patent Number:
7477534
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 to reduce audio frequencies in a switching power supply
Granted: December 30, 2008
Patent Number:
7471530
An apparatus and method of switching a switch of a power supply are disclosed. According to aspects of the present invention, a method includes controlling a switch of a switching power supply to switch on and off within a switching cycle. The switching cycle has a substantially fixed period. One group of consecutive switching cycles is separated from a next group of consecutive switching cycles by a time of no switching. Each group of consecutive switching cycles has at least a…
