Variable frequency timing circuit for a power supply control circuit
Granted: March 4, 2014
Patent Number:
8665620
A timing circuit of a controller generates a clock signal having a switching period for use by a pulse width modulation (PWM) circuit to control a switch of a power supply. The switching period of the clock signal is based on a charging time plus a discharging time of a capacitor included in the timing circuit. A first current source charges the capacitor while the timing circuit is in a normal charging mode. A second current source charges the capacitor while the timing circuit is in an…
Method and apparatus for increasing the power capability of a power supply
Granted: March 4, 2014
Patent Number:
8665615
One controller for a power supply includes an oscillator, a first circuit, a counter, and a pause circuit. The first circuit generates a drive signal to control switching of a switch to regulate an output of the power supply. The first circuit initiates an on time period of the switch in response to both a clock signal of the oscillator and an enable signal that is generated in response to a feedback signal of the power supply. The counter receives the enable signal and generates an…
Self-aligned semiconductor devices with reduced gate-source leakage under reverse bias and methods of making
Granted: February 25, 2014
Patent Number:
8659057
A vertical junction field effect transistor (VJFET) having a self-aligned pin, a p+/n/n+ or a p+/p/n+ gate-source junction is described. The device gate can be self-aligned to within 0.5 ?m to the source in order to maintain good high voltage performance (i.e. low DIBL) while reducing gate-source junction leakage under reverse bias. The device can be a wide-bandgap semiconductor device such as a SiC vertical channel junction field effect. Methods of making the device are also described.
Method and apparatus for digital control of a switching regulator
Granted: February 18, 2014
Patent Number:
8654547
In one aspect, a power supply includes an energy transfer element, a switch, a feedback circuit, a comparator, a state machine, and a control circuit. The feedback circuit generates a feedback signal representative of an output level of the power supply. The comparator provides a feedback state signal having a first feedback state that represents the output level of the power supply being above a threshold level and a second feedback state that represents the output level being below the…
High-voltage monolithic schottky device structure
Granted: February 18, 2014
Patent Number:
8653600
A semiconductor device includes a pillar formed on a substrate of the same conductivity type. The pillar has a vertical thickness that extends from a top surface down to the substrate. The pillar extends in first and second lateral directions in a loop shape. First and second dielectric regions are disposed on opposite lateral sides of the pillar, respectively. First and second conductive field plates are respectively disposed in the first and second dielectric regions. A metal layer is…
Sensing FET integrated with a high-voltage transistor
Granted: February 18, 2014
Patent Number:
8653583
In one embodiment, a semiconductor device includes a main vertical field-effect transistor (FET) and a sensing FET. The main vertical FET and the sense FET are both formed on a pillar of semiconductor material. Both share an extended drain region formed in the pillar above the substrate, and first and second gate members formed in a dielectric on opposite sides of the pillar. The source regions of the main vertical FET and the sensing FET are separated and electrically isolated in a…
Adjacent terminal fault detection
Granted: February 4, 2014
Patent Number:
8643983
This relates to detecting unwanted couplings between a protected terminal and other terminals in an integrated controller of a power supply. Offset and clamp circuitry may apply a positive or negative offset voltage and clamp current to one or more terminals of the controller. In the event that a terminal having the offset voltage and clamp current is accidentally coupled to the protected terminal, the offset voltage and clamp current may be applied to the protected terminal. The…
Apparatus and method for detecting a change in output voltage of an isolated power converter
Granted: January 28, 2014
Patent Number:
8638572
A power converter controller includes a drive circuit coupled to control switching of a power switch coupled to an energy transfer element and an input of the power converter. An output voltage sensor including first and second pulse sampler circuits is coupled to capture first and second peak voltages, respectively, that are representative of a second peak of a ringing voltage of a feedback signal representative of an output of the power converter. The first pulse sampler circuit is…
Electrostatic discharge conducting pathway having a noise filter spark gap
Granted: January 28, 2014
Patent Number:
8638536
A printed circuit board includes a primary region, a secondary region and an isolation region disposed between the primary region and the secondary region to galvanically isolate the primary region from the secondary region. The primary region is to be coupled to an AC source. The primary region also includes an electrostatic discharge (ESD) conducting pathway to redirect current to the AC source that crosses the isolation region. A spark gap is included in the ESD conducting pathway.
Monolithic AC/DC converter for generating DC supply voltage
Granted: January 21, 2014
Patent Number:
8634218
An integrated circuit (IC) comprises a rectifier/regulator circuit coupled to receive an ac source voltage and output a regulated dc voltage. The rectifier/regulator circuit includes first and second switching elements that provide charging current when enabled. The first and second switching elements do not provide charging current when disabled. A sensor circuit is coupled to sense the regulated dc voltage and generate a feedback control signal coupled to the rectifier/regulator…
Power supply circuit with a control terminal for different functional modes of operation
Granted: January 21, 2014
Patent Number:
8634213
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…
GaN high voltage HFET with passivation plus gate dielectric multilayer structure
Granted: January 21, 2014
Patent Number:
8633094
A method of fabricating a multi-layer structure for a power transistor device includes performing, within a reaction chamber, a nitrogen plasma strike, resulting in the formation of a nitride layer directly on a nitride-based active semiconductor layer. A top surface of the nitride layer is then exposed to a second source. A subsequent nitrogen-oxygen plasma strike results in the formation of an oxy-nitride layer directly on the nitride layer. The nitride layer comprises a passivation…
Method and apparatus for programming a power converter controller with an external programming terminal having multiple functions
Granted: January 14, 2014
Patent Number:
8630103
A power converter controller is disclosed. An example controller includes a control circuit coupled to receive a feedback signal representative of an output of the power converter. The control circuit coupled to control a switching of a power switch of the power converter in response to the feedback signal to control a transfer of energy from an input of the power converter to the output of the power converter. An internal programming interface circuit is coupled to the control circuit.…
Ultra low standby consumption in a high power power converter
Granted: January 14, 2014
Patent Number:
8630102
A power converter includes a dc input having first and second terminals. A main converter is coupled to the first terminal of the dc input. A standby circuit coupled to the second terminal of the dc input and the main converter. The main converter is coupled to control a transfer of energy from the dc input through the standby circuit to a main output of the main converter during a normal operating condition of the power supply. The standby circuit is coupled to decouple the main…
Second contact schottky metal layer to improve GaN schottky diode performance
Granted: January 14, 2014
Patent Number:
8629525
A Schottky diode includes a first nitride-based semiconductor layer disposed atop a substrate. A second nitride-based semiconductor layer is disposed atop a portion of the first nitride-based semiconductor layer. The second layer has a doping concentration lower than that of the first layer. A first Schottky contact metal layer having a first metal work function is disposed on a top planar surface of the second layer, forming a first Schottky junction. A second Schottky contact metal…
Asymmetric switch forward converter
Granted: January 7, 2014
Patent Number:
8625312
A switching circuit for use in a power converter includes a first active switch coupled between a first terminal of an input of the power converter and a first terminal of a primary winding of a transformer. A second active switch is coupled between a second terminal of the input and a second terminal of the primary winding. An output capacitance of the first active switch is greater than an output capacitance of the second active switch. A first passive switch is coupled between the…
Method and apparatus for implementing a power converter input terminal voltage discharge circuit
Granted: January 7, 2014
Patent Number:
8624562
A switch is coupled to a control circuit and to an input of a power converter. The control circuit is coupled to drive the switch in a first operating mode to transfer energy from the input to an output of the power converter when an electrical energy source is coupled to the input of the power converter. The control circuit is coupled to drive the switch in a second operating mode when the electrical energy source is uncoupled from the input. A capacitance is coupled between input…
Feed forward imbalance corrector circuit
Granted: January 7, 2014
Patent Number:
8624514
A circuit includes a first active device is coupled between a third terminal and a second terminal. The first active device has a control terminal coupled a first terminal to receive a signal representative of a rectified input voltage. A second active device is coupled between the control terminal of the first active device and the second terminal. The second active device has a control terminal coupled to a fourth terminal. The second active device is coupled to be controlled in…
Energy transfer assembly with tuned leakage inductance and common mode noise compensation
Granted: December 24, 2013
Patent Number:
8614615
An energy transfer assembly with tuned leakage inductance and common mode noise compensation is disclosed. An example energy transfer assembly for use in a resonant power converter includes a first winding wound around a bobbin mounted on a magnetic core. The first winding has a first number of layers proximate to a first end along a length of the bobbin and a second number of layers proximate to a second end along the length of the bobbin. The energy transfer assembly also includes a…
Controller with punctuated switching control circuit
Granted: December 17, 2013
Patent Number:
8610409
An example controller for use in a power supply includes a zero crossing detection (ZCD) circuit, a threshold detection circuit, and a punctuated switching control circuit. The ZCD circuit generates a ZCD signal that pulses each zero-crossing of an ac input voltage. The threshold detection circuit receives and compares an output of the power supply with a threshold reference. The punctuated switching control circuit generates a switching signal to control a switch to regulate the output…
