Alpha & Omega Semiconductor Patent Grants

Gas dopant doped deep trench super junction high voltage MOSFET

Granted: January 31, 2023
Patent Number: 11569345
A method for manufacturing and a Super Junction MOSFET are disclosed. The Super Junction MOSFET comprises a lightly doped epitaxial layer of a first conductivity type on a heavily doped substrate of the first conductivity type. A deep trench is formed in the epitaxial layer. The deep trench having an insulating layer with a thickness gradient formed on surfaces of the deep trench. One or more regions of the epitaxial layer proximate to sidewalls of the deep trench is doped of a second…

Silicon carbide MOSFET with source ballasting

Granted: January 10, 2023
Patent Number: 11552078
A method for making an integrated device that includes a plurality of planar MOSFETs, includes forming a plurality of doped body regions in an upper portion of a silicon carbide substrate composition and a plurality of doped source regions. A first contact region is formed in a first source region and a second contact region is formed in a second source region. The first and second contact regions are separated by a JFET region that is longer in one planar dimension than the other. The…

Fast transient response in DC-to-DC converters

Granted: December 27, 2022
Patent Number: 11539293
A capacitor is discharged to a point where ring back in an output voltage across the capacitor is eliminated in response a transient event to high side and low side switching devices conductively coupled to an inductor and the capacitor before turning on the high side switch and varying an output voltage with a change in a load current.

Schottky diode integrated into superjunction power MOSFETs

Granted: December 27, 2022
Patent Number: 11538933
A trench metal-oxide-semiconductor field-effect transistor (MOSFET) device comprises an active cell area including a plurality of superjunction trench power MOSFETs, and a Schottky diode area including a plurality of Schottky diodes formed in the drift region having the superjunction structure. Each of the integrated Schottky diodes includes a Schottky contact between a lightly doped semiconductor layer and a metallic layer.

Inductor binning enhanced current sense

Granted: December 6, 2022
Patent Number: 11522451
An apparatus, comprising, a MOSFET, a controller coupled to the MOSFET, an inductor conductively coupled to the MOSFET. A reported current output of the controller is adjusted based on a predetermined excursion of an attribute of the inductor from a fixed attribute value.

Autonomous current sharing for power stages

Granted: December 6, 2022
Patent Number: 11522448
Apparatus and associated methods relate to modulating a duty cycle in each of N interleaved power stages in response to determination whether a phase current is above or below an average of all phase output currents. In an illustrative example, the duty cycle modulation may increase or decrease delay on either the leading or trailing edges, which may fine-tune the phase PWM signal to correct the phase current to the average phase current. The modulation may be determined by comparing,…

Method for forming super-junction corner and termination structure with graded sidewalls

Granted: November 22, 2022
Patent Number: 11508819
A method for forming a superjunction power semiconductor device includes forming multiple epitaxial layers of a first conductivity type on a semiconductor substrate and implanting dopants of a second conductivity type into each epitaxial layer to form a first group of implanted regions in a first region and a second group of implanted regions in a second region in each epitaxial layer. The multiple epitaxial layers are annealed to form multiple columns of the second conductivity type…

Methods and apparatuses for auxiliary transient control system

Granted: November 15, 2022
Patent Number: 11502607
Apparatus and associated methods relate to providing an integrated circuit package having (a) a bypass circuit in parallel with an inductor and (b) a logic circuit configured to control the bypass circuit for conductivity modulation. In an illustrative example, in response to a corresponding load transient, the logic circuit may include a state machine configured to generate different control signals for the bypass circuit to control the timing and/or quantity of energy transfer from the…

Isolated converter with constant voltage mode and constant current mode and control method thereof

Granted: November 15, 2022
Patent Number: 11502592
An isolated converter has a constant voltage mode and a constant current mode. The isolated converter includes a transformer, a main switch, a driver, a controller, and an isolator. The controller includes a constant current control unit, a voltage comparator, and a control logic unit. The constant current control unit generates a voltage adjustment signal to adjust the reference voltage or voltage feedback signal according to a current feedback signal for sensing the output current. The…

Semiconductor package having thin substrate and method of making the same

Granted: November 8, 2022
Patent Number: 11495548
A semiconductor package comprises a semiconductor substrate, a first metal layer, an adhesive layer, a second metal layer, a rigid supporting layer, and a plurality of contact pads. A thickness of the semiconductor substrate is equal to or less than 50 microns. A thickness of the rigid supporting layer is larger than the thickness of the semiconductor substrate. A thickness of the second metal layer is larger than a thickness of the first metal layer. A method comprises the steps of…

Signal transmission circuit for providing control information from secondary side to primary side of power converter, and control circuit for power converter

Granted: October 25, 2022
Patent Number: 11482936
A signal transmission circuit is configured for transmitting control information from a secondary side of a power converter to a primary side of the power converter. The signal transmission circuit includes a transmitter circuit, a signal transformer and a detection circuit. The transmitter circuit is configured to generate a ramp signal at least according to a first control signal outputted from the secondary side. The first control signal indicates the control information provided for…

Digitally programmable, fully differential error amplifier

Granted: October 25, 2022
Patent Number: 11480987
An error amplifier circuit receives first and second input signals and provides an error amplifier output signal indicative of the difference between the first and second input signals. The error amplifier circuit implements a proportional-integrator-differentiator (PID) circuit having a differential input signal path and including a proportional amplifier circuit, an integrator amplifier circuit, and a differentiator amplifier circuit. The differentiator amplifier circuit receives an AC…

Flyback converter for controlling on time variation

Granted: October 18, 2022
Patent Number: 11476768
A flyback converter to control conduction time in AC/DC conversion technology. The flyback converter includes a primary side and a secondary side. The primary side includes a main switch connecting a primary coil to the input of the flyback converter in series. The secondary side includes a secondary coil coupling with the output terminal of the flyback converter. When a switching frequency of the main switch is at a preset first on time in the range between the off frequency and the…

Low capacitance bidirectional transient voltage suppressor

Granted: October 4, 2022
Patent Number: 11462532
A bidirectional transient voltage suppressor (TVS) circuit for data pins of electronic devices includes two sets of steering diodes and a diode triggered clamp device in some embodiment. In other embodiments, a bidirectional transient voltage suppressor (TVS) circuit for data pins of electronic devices includes two sets of steering diodes with a clamp device merged with a steering diode in each set. The TVS circuit is constructed to realize low capacitance at the protected nodes and…

USB type-C load switch ESD protection

Granted: September 27, 2022
Patent Number: 11456596
A MOSFET and an electrostatic discharge (ESD) protection device on a common chip includes a MOSFET with a source, a gate, and a drain, and an ESD protection device configured to implement a diode function that is biased to prevent current from flowing through the common chip from the source to the drain.

Charger

Granted: September 13, 2022
Patent Number: 11444000
A charger includes a thermal conductive plate for heat dissipation, and a transistor. The transistor includes a drain terminal of a first pulsating voltage level, and a source terminal of a second pulsating voltage level. The second pulsating voltage level is lower than the first pulsating voltage level. The source terminal is disposed closer to the thermal conductive plate than the drain terminal.

Power semiconductor package having integrated inductor, resistor and capacitor

Granted: April 19, 2022
Patent Number: 11309233
A power semiconductor package comprises a lead frame, a low side field-effect transistor (FET), a high side FET, a capacitor, a resistor, an inductor assembly, a first plurality of bonding wires, and a molding encapsulation. In one example, an entirety of the inductor assembly is disposed at a position higher than an entirety of the low side FET, higher than an entirety of the high side FET, and higher than an entirety of the first plurality of bonding wires. In another example, a bottom…

Method and apparatus for generating control signal and charging DC supply in a secondary synchronous rectifier

Granted: March 29, 2022
Patent Number: 11290021
A multi-function switch has a Junction-Field Effect Transistor (JFET) that outputs a voltage for both charging and timing/sense the synchronous rectifier controller. Current is provided to a synchronous rectifier controller from a JET having its drain conductively coupled to the drain electrode of the secondary side rectifying MOSFET, wherein the current from the source of the JET is used for both timing/sense and powering the synchronous rectifier controller. The JFET is biased for a…

Port controller with real-time fault detection

Granted: March 8, 2022
Patent Number: 11269390
A port controller circuit implements monitoring and detection of power path short failures by regulating the control voltage to the power switches during the on-state of the power switches. A failure condition is indicated when the control voltage to a power switch is regulated to a voltage level outside of a permissible range. The port controller circuit implements real-time monitoring where a short within the power path can be detected while the power path is enabled and the fault…

Intelligent power module control method for resonant converter

Granted: March 8, 2022
Patent Number: 11271559
A method of generating a gate drive signal for driving a control terminal of a power switch includes detecting a system input signal; determining a signal pulse of the system input signal being a first signal pulse following a power up event, or following an idle period, or following removal of a fault condition; and in response, generating a soft gate drive signal to drive the control terminal of the power switch to softly turn on the power switch. In another embodiment, the method…