Alpha & Omega Semiconductor Patent Grants

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…

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…

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…

Super-fast transient response (STR) AC/DC converter for high power density charging application

Granted: February 22, 2022
Patent Number: 11258270
A charger comprises a housing, a first multi-layer printed circuit board (PCB), a second multi-layer PCB, and a third multi-layer PCB. The first PCB comprises at least a portion of a primary side circuit. The second PCB comprises at least a portion of a secondary side circuit. The third PCB is perpendicular to the first PCB and the second PCB. An isolation coupling element is disposed on the third PCB. The isolation coupling element comprises a multi-layer PCB. The first PCB comprises a…

Silicon carbide trench semiconductor device

Granted: February 8, 2022
Patent Number: 11245016
A semiconductor apparatus has a silicon carbide substrate heavily doped with the first conductivity type and a lightly doped silicon carbide drift region of the first conductivity type over the silicon carbide substrate. A first body region in the drift region is doped with second conductivity type opposite the first. A first source region in the first body region is heavily doped with the first conductivity type. A gate trench is formed in the first source region and first body region.…

Semiconductor chip integrating high and low voltage devices

Granted: February 1, 2022
Patent Number: 11239312
The present invention is directed to a semiconductor chip comprising a high voltage device and a low voltage device disposed thereon. The chip may be formed in several different configurations. For example, the semiconductor chip may include a NPN bipolar transistor, PNP bipolar transistor, a diode, an N channel DMOS transistor and the like. the first doped well being configured as a base of the DMOS transistor, a P channel DMOS transistor and the like. These and other embodiments are…

Power stages and current monitor output signal (IMON) generation circuit

Granted: January 25, 2022
Patent Number: 11233454
Apparatus and associated methods relate to implementing an auto-inductance-detection architecture to reconstruct current monitor output (IMON) when a low-side switch in a power stage is on. In an illustrative example, an IMON generation circuit may include a variable resistor. A close loop control (e.g., OTA, switches, and variable resistor) may be configured to adjust a resistance value of the variable resistor automatically. The IMON generation circuit may also include a low pass…

Semiconductor package having enlarged gate pad and method of making the same

Granted: January 11, 2022
Patent Number: 11222858
A semiconductor package fabrication method comprises the steps of providing a wafer, applying a seed layer, forming a photo resist layer, plating a copper layer, removing the photo resist layer, removing the seed layer, applying a grinding process, forming metallization, and applying a singulation process. A semiconductor package comprises a silicon layer, an aluminum layer, a passivation layer, a polyimide layer, a copper layer, and metallization. In one example, an area of a contact…