METHOD AND APPARATUS TO LIMIT MAXIMUM SWITCH CURRENT IN A SWITCHING POWER SUPPLY
Granted: December 3, 2009
Application Number:
20090296427
Techniques are disclosed to limit the current in a switch of a switching power supply. An example switching regulator circuit includes a power switch to be coupled to an energy transfer element of a power supply. A controller to generate a drive signal is coupled to be received by the power switch to control the switching of the power switch. A short on time detector is included in the controller. The short on time detector is to detect an occurrence of a threshold number of one or more…
Segmented pillar layout for a high-voltage vertical transistor
Granted: November 5, 2009
Application Number:
20090273023
In one embodiment, a transistor fabricated on a semiconductor die includes a first section of transistor segments disposed in a first area of the semiconductor die, and a second section of transistor segments disposed in a second area of the semiconductor die adjacent the first area. Each of the transistor segments in the first and second sections includes a pillar of a semiconductor material that extends in a vertical direction. First and second dielectric regions are disposed on…
METHOD AND APPARATUS FOR A CONTROL CIRCUIT RESPONSIVE TO AN IMPEDANCE COUPLED TO A CONTROL CIRCUIT TERMINAL
Granted: October 29, 2009
Application Number:
20090268362
A power supply controller method and apparatus measuring impedance is disclosed. An apparatus according to aspects of the present invention includes a sense circuit coupled to a sense terminal. A regulation circuit coupled to the sense circuit and coupled to regulate the sense terminal to a first voltage level when a current flowing through the sense terminal is less than a first threshold current level. The regulation circuit is further coupled to regulate the sense terminal to a second…
METHOD AND APPARATUS TO IMPROVE REGULATION OF A POWER SUPPLY
Granted: October 22, 2009
Application Number:
20090262561
Techniques are disclosed to regulate a power supply with a compensation signal generation circuit. One example regulated power supply includes a sense circuit coupled to sense an output voltage of the regulated power supply. The regulated power supply also includes a switching power converter circuit, which includes a switch coupled to be switched in response to a control signal received from the sense circuit to regulate the output voltage of the regulated power supply. The regulated…
INTEGRATED SWITCH WITH INTERNALLY ADJUSTED CONDUCTION TIME
Granted: October 15, 2009
Application Number:
20090256536
An apparatus and method of providing a pulse width modulated signal that is responsive to a current are disclosed. An integrated circuit according to aspects of the present invention regulates an output of a power supply and includes a switch coupled to receive an external current. The integrated circuit also includes a controller coupled to the switch to control a switching of the external current by the switch in response to an external control signal and an internal current sense…
METHOD AND APPARATUS TO LIMIT OUTPUT POWER IN A SWITCHING POWER SUPPLY
Granted: October 15, 2009
Application Number:
20090256544
Techniques are disclosed to adjust a current limit in a switching regulator. One example switching regulator includes a comparator having first and second inputs and an output. The first input of the comparator is adapted to sense a current flow through a switch and the second input of the comparator is adapted to sense a variable current limit value. A controller is coupled to the output of the comparator and to the switch to control switching of the switch to regulate an output of a…
METHOD AND APPARATUS FOR CONDITIONAL RESPONSE TO A FAULT CONDITION IN A SWITCHING POWER SUPPLY
Granted: October 8, 2009
Application Number:
20090251931
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 REGULATING AN OUTPUT CURRENT FROM A POWER CONVERTER
Granted: October 8, 2009
Application Number:
20090251930
Techniques are disclosed to regulate an output current through a load coupled to a power converter using a current source coupled to the load. For instance, one power converter according to the teachings of the present invention includes an energy transfer element coupled between an input of the power converter and an output of the power converter. A power converter controller is coupled to the energy transfer element to control a transfer of energy from the input of the power converter…
METHOD AND APPARATUS FOR SUBSTANTIALLY REDUCING ELECTRICAL EARTH DISPLACEMENT CURRENT FLOW GENERATED BY WOUND COMPONENTS WITHOUT REQUIRING ADDITIONAL WINDINGS
Granted: October 8, 2009
Application Number:
20090251273
Apparatus for reducing electrical earth displacement current flow generated by wound components is disclosed. In one aspect, an apparatus includes a plurality of layers of an input winding wound around an energy transfer element core. An outer layer of the plurality of layers of the input winding is wound with a number of turns different than the number of turns in substantially each of the inner layers of the plurality of layers of the input winding. An output winding is wound around…
METHOD AND APPARATUS PROVIDING FINAL TEST AND TRIMMING FOR A POWER SUPPLY CONTROLLER
Granted: October 8, 2009
Application Number:
20090251121
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 AND APPARATUS FOR POWER CONVERSION AND REGULATION
Granted: October 8, 2009
Application Number:
20090251116
Techniques are disclosed to control a power converter with multiple output voltages. One example regulated power converter includes a an energy transfer element coupled between a power converter input and first and second power converter outputs. A switch is coupled between the power converter input and the energy transfer element such that switching of the switch causes a first output voltage to be generated at the first power converter output and a second output voltage to be generated…
METHOD AND APPARATUS FOR FAULT DETECTION IN A SWITCHING POWER SUPPLY
Granted: September 17, 2009
Application Number:
20090231888
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 AC TO DC POWER CONVERSION WITH REDUCED HARMONIC CURRENT
Granted: September 17, 2009
Application Number:
20090231889
A method and apparatus are disclosed for controlling a buck converter. In one aspect, an integrator is coupled to receive a current sense signal representative of a current in a switch of the buck converter and to integrate the current sense signal to produce a first input signal. A ramp generator is coupled to receive an oscillating signal having a same switching period as the switch, and to generate a piecewise linear ramp signal in response to the oscillating signal. The piecewise…
Method of fabricating a high-voltage transistor with an extended drain structure
Granted: September 17, 2009
Application Number:
20090233407
A method for fabricating a high-voltage transistor with an extended drain region includes forming in a semiconductor substrate of a first conductivity type, first and second trenches that define a mesa having respective first and second sidewalls; then partially filling each of the trenches with a dielectric material that covers the first and second sidewalls. The remaining portions of the trenches are then filled with a conductive material to form first and second field plates. Source…
METHOD AND APPARATUS TO PROVIDE TEMPORARY PEAK POWER FROM A SWITCHING REGULATOR
Granted: August 27, 2009
Application Number:
20090212755
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 AN IN-RUSH CURRENT LIMITING CIRCUIT
Granted: August 13, 2009
Application Number:
20090201619
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: August 13, 2009
Application Number:
20090201701
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 APPARATUS FOR REDUCING AUDIO NOISE IN A SWITCHING REGULATOR
Granted: August 6, 2009
Application Number:
20090195229
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 MODE SELECTION FOR HIGH VOLTAGE INTEGRATED CIRCUITS
Granted: July 30, 2009
Application Number:
20090189682
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 A CONTROL CIRCUIT WITH MULTIPLE OPERATING MODES
Granted: July 23, 2009
Application Number:
20090185396
An apparatus of 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…
