Power controller with smooth transition to pulse skipping
Granted: September 2, 2014
Patent Number:
8823353
A power converter control circuit includes a ramp signal circuit, a blanking circuit, and a pulse driver circuit. The ramp signal circuit provides a ramp signal in response to a power converter feedback signal and an enable signal. The blanking circuit provides a blanking signal in response to the ramp signal and a clock signal. The blanking signal is provided when both the ramp signal is increasing in value and the enable signal indicates a light load operating condition. The pulse…
High-voltage transistor structure with reduced gate capacitance
Granted: September 2, 2014
Patent Number:
8823093
In one embodiment, a high voltage field-effect transistor (HVFET) includes a field oxide layer that covers a first well region, the field oxide layer having a first thickness and extending in a second lateral direction from a drain region to near a second well region. A gate oxide covers a channel region and has a second dimension in a first lateral direction. A gate extends in the second lateral direction from the source region to over a portion of the field oxide layer, the gate being…
Second Schottky contact metal layer to improve GaN schottky diode performance
Granted: September 2, 2014
Patent Number:
8823013
A Schottky contact is disposed atop the surface of the semiconductor. A first Schottky contact metal layer is disposed atop a first portion of the semiconductor surface. A second Schottky contact metal is disposed atop a second portion of the surface layer and joins the first Schottky contact metal layer. A first. Schottky contact metal layer has a lower work function than the second Schottky contact metal layer.
Noise cancellation for a magnetically coupled communication link utilizing a lead frame
Granted: August 26, 2014
Patent Number:
8818296
An integrated circuit package includes an encapsulation and lead frame with a portion of the lead frame disposed within the encapsulation. The lead frame includes a first conductor formed in the lead frame having a first conductive loop and a third conductive loop disposed substantially within the encapsulation. A second conductor is formed in the lead frame galvanically isolated from the first conductor. The second conductor includes a second conductive loop disposed substantially…
Dimmer-disabled LED driver
Granted: August 26, 2014
Patent Number:
8816596
An integrated circuit controller for use in a light emitting diode (LED) driver includes a comparator, an input signal absence timer and a regulator circuit. The comparator receives a first voltage representative of an ac input signal and compares the first voltage with a reference voltage. The input signal absence timer determines whether the first voltage is less than the reference voltage for a threshold duration and in response thereto generates a detect signal indicating that a…
Checkerboarded high-voltage vertical transistor layout
Granted: August 26, 2014
Patent Number:
8816433
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…
Simplified current sense for buck LED driver
Granted: August 19, 2014
Patent Number:
8810157
A current sense and feedback circuit is provided for a non-isolated Buck power converter to maintain constant current load regulation. The Buck converter may have a high side power switch and may include an input port, a switcher unit including a switch and a controller, an inductor coupled to the output, and a freewheeling diode for circulating the inductor current when the switch is open. The simplified current sense and feedback circuit of the power converter may include a current…
Integrated on-time extension for non-dissipative bleeding in a power supply
Granted: August 12, 2014
Patent Number:
8803449
An example controller for a switched mode power supply includes a zero crossing detector, drive logic, and a logic gate. The zero-crossing detector generates a zero-crossing signal indicating a zero-crossing condition in the power supply. The drive logic generates a drive logic output signal in response to the zero-crossing signal and in response to a feedback signal, where the drive logic output signal is representative of an on-time of a switch to regulate an output of the power…
On time sampling prevention
Granted: August 5, 2014
Patent Number:
8797769
An example controller for a power converter includes a feedback sampling circuit, drive logic and a false sampling prevention circuit. The feedback sampling circuit is coupled to sample a feedback signal received from a terminal of the controller and to generate a sample signal representative of a value of the feedback signal. The drive logic is coupled to the feedback sampling circuit and coupled to control the power switch to regulate an output of the power converter in response to the…
Feedback circuit for non-isolated power converter
Granted: August 5, 2014
Patent Number:
8796950
A feedback circuit for a power converter (e.g., a non-isolated converter) is disclosed. The feedback circuit may include a sense circuit coupled to receive an output current of the converter. A sense voltage may be generated across the sense circuit and a voltage-to-current converter may be used to convert the sensed voltage into a feedback signal representative of the output current. The voltage-to-current converter may include a variable shunt regulator, resistor, and transistor. A…
Power semiconductor package with bottom surface protrusions
Granted: August 5, 2014
Patent Number:
8796560
A package includes a body that encapsulates a semiconductor die, the body having a first pair of opposing lateral sides, a second pair of opposing lateral sides, a top, and a bottom. The bottom has a primary surface and a plurality of protrusions that extend outward from the primary surface. When the package is mounted to a printed circuit board (PCB) the protrusions contact the PCB and the primary surface is disposed a first distance away from the PCB. The package further includes a…
Over-temperature protection of semiconductor components
Granted: July 29, 2014
Patent Number:
8791746
A device includes an over-temperature protection circuit configured to protect against over-temperature. The over-temperature protection circuit is coupled to receive a signal representative of temperature at the temperature sensor. The over-temperature protection circuit is coupled to adjust a temperature at which over-temperature protection is triggered based at least in part on a rate of change of the temperature at the temperature sensor.
Power system with shared clamp reset
Granted: July 15, 2014
Patent Number:
8780589
An example power supply includes a first power converter, a second power converter, and a shared clamp reset circuit. The first power converter is adapted to convert an input to a first voltage output and includes a first diode and a first transformer having a first primary winding. The second power converter is adapted to convert the input to a second voltage output and includes a second diode and a second transformer having a second primary winding. The shared clamp reset circuit is…
Detector circuit with low threshold voltage and high voltage input
Granted: July 15, 2014
Patent Number:
8779827
An integrated circuit includes a high voltage transistor having a first terminal coupled to sense a high voltage terminal and a control terminal coupled to a regulated voltage, which is regulated with respect to a ground terminal and is substantially less than a high voltage that the high voltage terminal is adapted to withstand. A logic gate is also included and is coupled to be powered from the regulated voltage. The logic gate has an input threshold that is less than the regulated…
Method and apparatus for sensing multiple voltage values from a single terminal of a power converter controller
Granted: July 8, 2014
Patent Number:
8773871
A controller for use in a power converter includes a sensor coupled to receive a signal from a single terminal of the controller. The signal from the single terminal represents an output voltage of the power converter during at least a portion of an off time of a power switch and a line input voltage during a portion of an on time of the power switch. A switching control is to be coupled to switch the power switch to regulate the output of the power converter in response to the sensor. A…
Method and apparatus for varying current limit to limit an output power of a power supply
Granted: July 1, 2014
Patent Number:
8767423
A power supply controller includes an input voltage sense input and an output voltage sense input coupled to sense an input voltage and an output voltage of a power supply. A current limit circuit includes a first variable resistance coupled in parallel with a second variable resistance. The first variable resistance responsive the input voltage of the power supply and the second variable resistance is responsive to the output voltage of the power supply. The current limit circuit is…
Method and apparatus for a control circuit with multiple operating modes
Granted: July 1, 2014
Patent Number:
8767414
An example controller for use in a power converter includes an oscillator that is to be coupled to a switch of the power converter to determine a switching cycle period of the switch. The controller also includes means for controlling a duty cycle of the switch to regulate an output of the power converter and for maintaining a substantially constant rate of change of the duty cycle with respect to changes in a magnitude of a feedback signal as the controller transitions between duty…
Transverse shroud and bobbin assembly
Granted: July 1, 2014
Patent Number:
8766756
A transformer assembly includes a vertical bobbin and a shrouding element. The vertical bobbin includes a first winding portion, a second winding portion, and a flange. The flange is disposed between the first winding portion and the second winding portion. The flange includes a flange edge. The shrouding element, which substantially covers the first winding portion or the second winding portion, includes a shrouding edge that is operatively coupled to the flange edge. The flange edge…
Deposit/etch for tapered oxide
Granted: July 1, 2014
Patent Number:
8765609
A process for fabricating a tapered field plate dielectric for high-voltage semiconductor devices is disclosed. The process may include depositing a thin layer of oxide, depositing a polysilicon hard mask, depositing a resist layer and etching a trench area, performing deep silicon trench etch, and stripping the resist layer. The process may further include repeated steps of depositing a layer of oxide and anisotropic etching of the oxide to form a tapered wall within the trench. The…
Method and apparatus for power converter fault condition detection
Granted: June 17, 2014
Patent Number:
8755201
An example controller includes a feedback circuit coupled to provide feedback information representative of an output of the power converter during at least a portion of an OFF time of a power switch. A sense input receives a sense signal that is representative of a reflected voltage representative of an input voltage of the power converter during at least a portion of an ON time of the power switch. A fault detector is to be coupled to detect a fault condition in response to the…
