DIGITAL-TO-ANALOG CONVERTER TO PRODUCE PAIRED CONTROL SIGNALS IN A POWER SUPPLY CONTROLLER
Granted: September 22, 2011
Application Number:
20110228567
An controller for use in a power supply includes a variable oscillator and a digital-to-analog converter (DAC). The variable oscillator generates a switching signal having an on-time and a switching period to control a first switch to regulate an output of the power supply. The DAC provides the variable oscillator with a first analog signal and a second analog signal, where the on-time of the switching signal is responsive to the first analog signal and where the switching period is…
OFF-LINE CONVERTER WITH DIGITAL CONTROL
Granted: September 22, 2011
Application Number:
20110228568
A circuit for regulating the level at a power converter output is disclosed. An example circuit includes an input for receiving a feedback signal. The feedback signal has a first feedback state that represents a level that is above a threshold level and a second feedback state that represents a level that is below the threshold level. An oscillator is included that provides an oscillation signal that cycles between two states. A switch having a first terminal, a second terminal and a…
PULSE WIDTH MODULATOR WITH TWO-WAY INTEGRATOR
Granted: September 22, 2011
Application Number:
20110227627
An example two-way integrator includes a first current source, a second current source, a first offset current source, a second offset current source, a capacitor, a switching reference and a comparator. The capacitor integrates a sum of a first input current and a first offset current by charging with both the first current source and the first offset current source. The capacitor subsequently integrates a sum of the second input current and the second offset current by discharging with…
Termination and contact structures for a high voltage GaN-based heterojunction transistor
Granted: September 8, 2011
Application Number:
20110215339
A semiconductor device is provided that includes a substrate, a first active layer disposed over the substrate, and a second active layer disposed on the first active layer. The second active layer has a higher bandgap than the first active layer such that a two-dimensional electron gas layer arises between the first active layer and the second active layer. A termination layer, which is disposed on the second active layer, includes InGaN. Source, gate and drain contacts are disposed on…
METHOD AND APPARATUS TO REDUCE AUDIO FREQUENCIES IN A SWITCHING POWER SUPPLY
Granted: September 1, 2011
Application Number:
20110211373
An example controller for use in a power supply regulator includes a switch signal generator, a modulation circuit, and a multi-cycle modulator circuit. The modulation circuit modulates the duty cycle of a pulse width modulated switching signal to provide a fixed peak switching current in the switch during light load conditions and a variable peak switching current during load conditions other than the light load condition. The multi-cycle modulator circuit enables the switch signal…
METHOD AND APPARATUS FOR A HIGH VOLTAGE POWER SUPPLY CIRCUIT
Granted: August 18, 2011
Application Number:
20110199795
A power converter is disclosed. An example power converter includes an energy transfer element coupled between a power converter input and a power converter output. A power switch is coupled to the energy transfer element. A control circuit is coupled to receive a feedback signal representative of the power converter output during a feedback portion of an off time of the power switch. The control circuit is coupled to generate an output signal in response to the feedback signal. The…
METHOD AND APPARATUS FOR IMPLEMENTING AN UNREGULATED DORMANT MODE IN A POWER CONVERTER
Granted: August 18, 2011
Application Number:
20110199798
A control circuit for use in a power converter with an unregulated dormant mode of operation is disclosed. In one aspect a power converter includes a drive signal generator that is coupled to generate a drive signal to control switching of a power switch coupled to the control circuit to regulate a flow of energy to an output of the power converter in response to an energy requirement of one or more loads coupled to the output of the power converter. A regulator circuit is coupled to…
PHASE ANGLE MEASUREMENT OF A DIMMING CIRCUIT FOR A SWITCHING POWER SUPPLY
Granted: August 11, 2011
Application Number:
20110194311
An example controller for a switched mode power supply includes a zero-crossing detector, a feedback reference circuit, and a drive signal generator. The zero-crossing detector is coupled to generate a zero-crossing signal representative of a length of time that a zero-crossing condition of an input voltage of the power supply exists. The feedback reference circuit is to be coupled to receive a feedback signal and a reference signal, where the feedback signal is representative of an…
Power supply circuit with a control terminal for different functional modes of operation
Granted: August 11, 2011
Application Number:
20110194315
A method of operation for flyback power converter includes operating a controller of the flyback power converter in a regulation mode when a control signal is below a first threshold. The control signal is provided as an input to a terminal of the flyback power converter. When the control signal is below a second threshold and above the first threshold, the controller is operated in a limiting mode. The controller is operated in an external command mode when the control signal is below a…
METHOD AND APPARATUS FOR DETERMINING ZERO-CROSSING OF AN AC INPUT VOLTAGE TO A POWER SUPPLY
Granted: August 11, 2011
Application Number:
20110194312
An example controller for a switched mode power supply includes a drive signal generator and a zero-crossing detector. The drive signal generator is to be coupled to control switching of a switch included in the power supply to regulate an output of the power supply. The zero-crossing detector is coupled to the drive signal generator and coupled to receive a current sense signal representative of a switch current flowing through the switch. The zero-crossing detector generates a…
FORWARD CONVERTER TRANSFORMER SATURATION PREVENTION
Granted: August 11, 2011
Application Number:
20110194310
A power converter in one aspect limits the magnetic flux in a transformer. A control circuit included in the power converter includes a pulse width modulator, logic circuits and saturation prevention circuits. The saturation prevention circuits assert a first signal when a first integral value of the input voltage reaches a first threshold value and assert a second signal after a delay time that begins when a difference between the first integral value and a second integral value of a…
METHOD AND APPARATUS TO CONTROL A POWER CONVERTER HAVING A LOW LOOP BANDWIDTH
Granted: August 11, 2011
Application Number:
20110194309
A power converter controller is disclosed. An example power converter controller includes a feedback sensor circuit coupled to receive a feedback signal representative of an output of the power converter. The controller also includes a feedback sampling signal generator coupled to generate a feedback sampling signal coupled to be received by the feedback sensor circuit. The feedback sensor circuit is coupled to sample the feedback signal in response to the feedback sampling signal. The…
INTEGRATED ON-TIME EXTENSION FOR NON-DISSIPATIVE BLEEDING IN A POWER SUPPLY
Granted: August 11, 2011
Application Number:
20110193494
An example controller for a switched mode power supply includes a zero-crossing detector, drive logic, and an on-time extension block. The zero-crossing detector is coupled to generate a first signal prior to a zero-crossing of an input voltage of the power supply. The drive logic is to generate a drive logic output signal in response to a feedback signal, where the drive logic output signal is representative of an initial on-time. The on-time extension block is coupled to the…
FAULT CONDITION PROTECTION
Granted: August 4, 2011
Application Number:
20110188274
A regulator for a switched mode power supply includes switching regulator logic, a counter and a switching transistor. The switching regulator logic is coupled to receive a feedback signal and to generate a switching signal in response. The feedback signal periodically cycles between a first state and a second state when the power supply operates normally. The counter is coupled to receive the feedback signal and an output of the counter indicates an auto-restart mode of the regulator in…
COMPACT DIGITAL-TO-ANALOG CONVERTER
Granted: July 28, 2011
Application Number:
20110181453
A digital-to-analog converter is disclosed. An example digital-to-analog converter circuit includes a reference scaling circuit coupled to receive a first reference current. The reference scaling circuit is coupled to generate a second reference current in response to the first reference current. The digital-to-analog converter circuit also includes a first plurality of binary-weighted current sources coupled to a summing node. A current of a first one of the first plurality of…
POWER CONVERTER HAVING A SWITCH COUPLED BETWEEN WINDINGS
Granted: June 30, 2011
Application Number:
20110156675
An example power converter includes a first winding, a second winding, a switch, a controller and an output circuit. The second winding is magnetically coupled to the first winding and the controller includes a feedback terminal and a common terminal. The controller is coupled to control the switch to regulate an output of the power converter in response to a feedback voltage received at the feedback terminal. The output circuit is coupled between the common terminal of the controller…
POWER CONVERTER HAVING A SWITCH COUPLED BETWEEN WINDINGS
Granted: June 30, 2011
Application Number:
20110156689
An example power converter includes a first winding, a second winding, a switch, and a controller. The second winding is magnetically coupled to the first winding and the switch is coupled between the first winding and the second winding such that a current flows through the first winding, the second winding and the switch when the switch is in an ON state. The controller is coupled to control the switch to regulate an output of the power converter in response to a feedback signal.
METHOD AND APPARATUS TO REDUCE LINE CURRENT HARMONICS FROM A POWER SUPPLY
Granted: June 30, 2011
Application Number:
20110157943
A method and apparatus for controlling a power converter. In one aspect, a controller for use in a power converter includes a first calculator coupled to determine an end of an on time of a power switch of the power converter by integrating an input current to output an on time signal representative of the end of the on time of the power switch. The controller also includes a second calculator coupled to determine an end of an off time of the power switch by integrating a difference…
DIGITAL-TO-ANALOG CONVERTER TO PRODUCE PAIRED CONTROL SIGNALS IN A POWER SUPPLY CONTROLLER
Granted: June 23, 2011
Application Number:
20110148681
An example digital-to-analog converter (DAC) for a power supply controller includes a first node, a second node, a current source, and a switch. The first node is to be coupled to provide a first analog signal to a variable oscillator of the power supply controller. The second node is to be coupled to provide a second analog signal to the variable oscillator of the power supply controller. The switch is coupled to the current source and configured to couple the current source to the…
METHOD AND APPARATUS FOR LIMITING MAXIMUM OUTPUT POWER OF A POWER CONVERTER
Granted: June 23, 2011
Application Number:
20110149615
An example power converter includes an energy transfer element, a switch, a controller, and a current offset circuit. The controller is coupled to switch the switch between an ON state and an OFF state to regulate the output of the power converter. The controller is also adapted to terminate the ON state of the switch in response to a switch current flowing through the switch reaching a switch current threshold. An auxiliary winding of the energy transfer element is adapted to generate…
