IXYS Patent Grants

Gate driver that drives with a sequence of gate resistances

Granted: November 7, 2017
Patent Number: 9813055
A gate driver integrated circuit for driving a gate of an IGBT or MOSFET receives an input signal. In response to a rising edge of the input signal, the integrated circuit causes the gate to be driven in a first sequence of time periods. In each period, the gate is driven high (pulled up) via a corresponding one of a plurality of different effective gate resistances. In response to a falling edge of the input signal, the integrated circuit causes the gate to be driven in a second…

Buck converter having self-driven BJT synchronous rectifier

Granted: October 24, 2017
Patent Number: 9800159
A switching converter has a self-driven bipolar junction transistor (BJT) synchronous rectifier. The BJT rectifier includes a BJT and a parallel-connected diode, and has a low forward voltage drop. In a first portion of a switching cycle, a main switch is on and the BJT rectifier is off. Current flows from an input, through the main switch, through the first inductor, to an output. Current also flows through the main switch, through the second inductor, to the output. In a second portion…

Method of joining metal-ceramic substrates to metal bodies

Granted: October 17, 2017
Patent Number: 9790130
A method of joining a metal-ceramic substrate having metallization on at least one side to a metal body by using metal alloy is disclosed. The metal body has a thickness of less than 1.0 mm and the metal alloy contains aluminum and has a liquidus temperature of greater than 450° C. The resulting metal-ceramic module provides a strong bond between the metal body and the ceramic substrate. The resulting module is useful as a circuit carrier in electronic appliances, with the metal body…

IGBT assembly having saturable inductor for soft landing a diode recovery current

Granted: October 17, 2017
Patent Number: 9793352
A combination switch includes an Insulated Gate Bipolar Transistor (IGBT), an anti-parallel diode, and a saturable inductor. The diode and inductor are coupled in series between a collector and an emitter of the IGBT. The inductor is fashioned so that it will come out of saturation when a forward bias current flow through the diode falls below a saturation current level. When the diode current falls (for example, due to another combination switch of a phase leg turning on), the diode…

IGBT with waved floating P-well electron injection

Granted: October 3, 2017
Patent Number: 9780168
An IGBT includes a floating P well, and a floating N+ well that extends down into the floating P well. A bottom surface of the floating P well has a waved contour so that it has thinner portions and thicker portions. When the device is on, electrons flow laterally from an N+ emitter, and through a first channel region. Some electrons pass downward, but others pass laterally through the floating N+ well to a local bipolar transistor located at a thinner portion of the floating P type…

Trench IGBT with waved floating P-well electron injection

Granted: October 3, 2017
Patent Number: 9780202
A trench IGBT includes a floating P well and a floating N+ well that extends down into the floating P well. A bottom surface of the floating P well has a novel waved contour so that it has thinner portions and thicker portions. When the IGBT is on, electrons flow from an N+ emitter, vertically through a channel along a trench sidewall, and to an N? type drift layer. Additional electrons flow through the channel but then pass under the trench, through the floating P well to the floating…

Synchronous sensing of inductor current in a buck converter control circuit

Granted: October 3, 2017
Patent Number: 9780648
A sense resistor is placed in series with an output capacitor of a buck converter. The buck converter operates in a discontinuous mode such that there is a dead time in each switching cycle. A control circuit senses a voltage across the sense resistor and thereby generates a first signal ICS. The control circuit detects an offset voltage in ICS, where the offset voltage is the voltage of ICS during the dead time in a first switching cycle. The control circuit level shifts the entire ICS…

Die stack assembly using an edge separation structure for connectivity through a die of the stack

Granted: July 11, 2017
Patent Number: 9704832
A die stack assembly includes first and second power semiconductor device dice. The first die has a P type peripheral edge separation structure that extends from the top planar semiconductor surface of the first die all the way to the bottom planar semiconductor surface of the die, and that is doped at least in part with aluminum. The backside of the first die is mounted to the backside of the second die. A metal feature that is not covered with passivation, and that can serve as a…

Low forward voltage rectifier

Granted: July 11, 2017
Patent Number: 9705417
A rectifier includes a larger Field Effect Transistor (FET1) and a smaller FET (FET2). A sense resistor is in series with FET2's body diode between a cathode terminal and an anode terminal. If the cathode terminal voltage is greater than the voltage on the anode terminal, then body diodes of FETs are reverse biased, the FETs are controlled to be off, and there is no current flow through the rectifier. If, however, the voltage on the anode terminal becomes positive with respect to the…

Chopper stabilized amplifier with synchronous switched capacitor noise filtering

Granted: July 4, 2017
Patent Number: 9698741
A chopper stabilzed amplifier with synchronous switched capacitor noise filtering is disclosed. In an exemplary embodiment, an apparatus includes a chopper amplifier having an input that receives an input signal and an output that outputs an amplified signal. The chopper amplifier includes an input chopping circuit and an output chopping circuit, where the input and output chopping circuits operate in response to a chop clock. The apparatus also includes a switched capacitor filter…

Bridging DMB structure for wire bonding in a power semiconductor module

Granted: May 2, 2017
Patent Number: 9640461
A power module includes a substrate DMB (Direct Metal Bonded). A novel bridging DMB is surface mounted to the substrate DMB along with power semiconductor device dice. The top metal layer of the bridging DMB has one or more islands to which bonding wires can connect. In one example, an electrical path extends from a module terminal, through a first bonding wire and to a first location on a strip-shaped island, through the island to a second location, and from the second location and…

AC line filter and AC-to-DC rectifier module

Granted: May 2, 2017
Patent Number: 9641065
An AC line filter module includes AC-to-DC rectification circuitry. The rectification circuitry includes four low forward voltage rectifiers coupled together as two high-side rectifiers and two low-side rectifiers, where each low forward voltage rectifier includes an NPN bipolar transistor and a parallel-connected diode. A current splitting pair of inductors splits a return current so that a portion of the current is supplied to the collector of an NPN bipolar transistor that is on, and…

Trench IGBT with tub-shaped floating P-well and hole drains to P-body regions

Granted: April 18, 2017
Patent Number: 9627521
A trench IGBT has a gate electrode disposed in a trench. A tub-shaped floating P-well is disposed on one side of the trench. The tub-shaped floating P-well has a central shallower portion and a peripheral deeper portion. An inner sidewall of the trench is semiconductor material of the peripheral deeper portion of the floating P-well. On the other side of the trench is a P type body region involving a plurality of deeper portions and a plurality of shallower portions. Each deeper portion…

Power device cassette with auxiliary emitter contact

Granted: March 21, 2017
Patent Number: 9601473
A press pack module includes a collector module terminal, an emitter module terminal, a gate module terminal, and an auxiliary module terminal. Each IGBT cassette within the module includes a set of shims, two contact pins, and an IGBT die. The first contact pin provides part of a first electrical connection between the gate module terminal and the IGBT gate pad. The second contact pin provides part of a second electrical connection between the auxiliary module terminal and a shim that…

High-voltage stacked transistor circuit

Granted: March 14, 2017
Patent Number: 9595950
A High-Voltage Stacked Transistor Circuit (HVSTC) includes a stack of power transistors coupled in series between a first terminal and a second terminal. The HVSTC also has a control terminal for turning on an off the power transistors of the stack. All of the power transistors of the stack turn on together, and turn off together, so that the overall stack operates like a single transistor having a higher breakdown voltage. Each power transistor, other than the one most directly coupled…

Reverse bipolar junction transistor integrated circuit

Granted: March 7, 2017
Patent Number: 9589953
A Reverse Bipolar Junction Transistor (RBJT) integrated circuit comprises a bipolar transistor and a parallel-connected distributed diode, where the base region is connected neither to the collector electrode nor to the emitter electrode. The bipolar transistor has unusually high emitter-to-base and emitter-to-collector reverse breakdown voltages. In the case of a PNP-type RBJT, an N base region extends into a P? epitaxial layer, and a plurality of P++ collector regions extend into the…

Trench separation diffusion for high voltage device

Granted: March 7, 2017
Patent Number: 9590033
A manufacturable and economically viable edge termination structure allows a semiconductor device to withstand a very high reverse blocking voltage (for example, 8500 volts) without suffering breakdown. A P type peripheral aluminum diffusion region extends around the bottom periphery of a thick die. The peripheral aluminum diffusion region extends upward from the bottom surface of the die, extending into N? type bulk silicon. A deep peripheral trench extends around the upper periphery of…

Super junction field effect transistor with internal floating ring

Granted: March 7, 2017
Patent Number: 9590092
A Super Junction Field Effect Transistor (FET) device includes a charge compensation region disposed on a substrate of semiconductor material. The charge compensation region includes a set of strip-shaped P? type columns, a floating ring-shaped P? type column that surrounds the set of strip-shaped P? type columns, and a set of ring-shaped P? type columns that surrounds the floating ring-shaped P? type column. A source metal is disposed above portions of the charge compensation region.…

Non-isolated AC-to-DC converter with fast dep-FET turn on and turn off

Granted: February 14, 2017
Patent Number: 9571003
Within a non-isolated and efficient AC-to-DC power supply circuit: 1) a dep-FET is turned off to decouple an output voltage VO node from a VR node when a rectifier output signal VR on the VR node is greater than a first predetermined voltage VP and, 2) the dep-FET is enabled to be turned on so that a constant charging current flows from the VR node and onto the VO node when VR is less than VP (provided that VO is less than a second predetermined voltage VO(MAX) and provided that VR is…

Loading a machine code API onto an 8-bit virtual machine to enable new functionality

Granted: January 10, 2017
Patent Number: 9542212
A compact, register-based, eight-bit virtual machine is realized on a resource-constrained device such as, for example, an IR remote control device. The IR remote control device includes a script interpreter, as well as loader API functionality and API functionality to support communication over a bidirectional link. The functionality of the remote control device is customized by loading either a machine code API routine and/or a script API routine onto the remote control device via the…