IXYS Corporation Patent applications |
Patent application number | Title | Published |
20150155785 | BUCK CONVERTER HAVING SELF-DRIVEN BJT SYNCHRONOUS RECTIFIER - 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 of the cycle, the main switch is turned off but the inductor currents continue to flow. Current flows from a ground node, through the BJT rectifier, through the first inductor, to the output. The BJT is on due to the second inductor drawing a base current from the BJT. In one example, the main switch is a split-source NFET that conducts separate currents through the two inductors. | 06-04-2015 |
20150138839 | FORWARD CONVERTER WITH SELF-DRIVEN BJT SYNCHRONOUS RECTIFIER - An AC-to-DC converter circuit includes DC-to-DC converter that in turn includes a secondary side circuit. The secondary side circuit includes a secondary winding, a pair of bipolar transistor-based self-driven synchronous rectifiers, a pair of current splitting inductors, and an output capacitor. Each of the synchronous rectifiers includes a bipolar transistor and a diode whose anode is coupled to the transistor collector and whose cathode is coupled to the transistor emitter. The current splitting inductors provide the necessary base current to the bipolar transistors at the appropriate times such that the bipolar transistors operate as synchronous rectifiers. As compared to using conventional self-driven synchronous rectifiers based on field effect transistors in the secondary side, using the novel bipolar-transistor based synchronous rectifiers in the secondary side of the forward converter circuit results in lower power consumption and allows the converter to operate from a wider range of VAC input voltages. | 05-21-2015 |
20150102481 | SINTERED BACKSIDE SHIM IN A PRESS PACK CASSETTE - Within a cassette of a press pack module, a conductive shim is bonded to the backside of a device die by a layer of sintered metal. The die, sintered metal, and shim together form a sintered assembly. The cassette is compressed between a metal top plate member and a metal bottom plate member such that the backside of the assembly is pressed against the top plate member, and such that the frontside of the assembly is pressed against another shim. A central portion of the frontside surface of the die is contacted on the bottom by the other shim, but there is no shim contacting a peripheral portion of the frontside surface. Despite there being no shim in contact with the peripheral portion of the frontside surface, the peripheral portion is in good thermal contact with the top plate member through the sintered metal and the bonded conductive shim. | 04-16-2015 |
20150102383 | POWER DEVICE CASSETTE WITH AUXILIARY EMITTER CONTACT - 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 in turn contacts the IGBT emitter pad. The electrical connection between the auxiliary emitter terminal and each emitter pad of the many IGBTs is a balanced impedance network. The balanced network is not part of the high current path through the module. By supplying a gate drive signal between the gate and auxiliary emitter terminals, simultaneous IGBT turn off in high speed and high current switching conditions is facilitated. | 04-16-2015 |
20140332842 | PACKAGED OVERVOLTAGE PROTECTION CIRCUIT FOR TRIGGERING THYRISTORS - In a first embodiment, an ultra-fast breakover diode has a turn on time T | 11-13-2014 |
20140332841 | HIGH VOLTAGE BREAKOVER DIODE HAVING COMPARABLE FORWARD BREAKOVER AND REVERSE BREAKDOWN VOLTAGES - In a first embodiment, an ultra-fast breakover diode has a turn on time T | 11-13-2014 |
20140273384 | POWER TRANSISTOR WITH INCREASED AVALANCHE CURRENT AND ENERGY RATING - A field-effect transistor involves a drain electrode, a drift region, a body region, a source region, a gate insulator layer, and a gate electrode. The drift region is disposed above the drain electrode. The body region extends down into the drift region from a first upper semiconductor surface. The source region is ladder-shaped and extends down in the body region from a second upper semiconductor surface. The first and second upper semiconductor surfaces are substantially planar and are not coplanar. A first portion of the body region is surrounded laterally by a second portion of the body region. The second portion of the body region and the drift region meet at a body-to-drift boundary. The body-to-drift boundary has a central portion that is non-planar. A gate insulator layer is disposed over the source region and a gate electrode is disposed over the gate insulator. | 09-18-2014 |
20140273357 | Vertical Power MOSFET And IGBT Fabrication Process With Two Fewer Photomasks - A process for fabrication of a power semiconductor device is disclosed in which a single photomask is used to define each of p-conductivity well regions and n-conductivity type source regions. In the process a single photomask is deposited on a layer of polysilicon on a wafer, the polysilicon layer is removed from first regions of the power semiconductor device where the p-conductivity well regions and the n-conductivity type source regions are to be formed, and both p-conductivity type and n-conductivity type dopants are introduced into the wafer through the first regions. | 09-18-2014 |
20140252410 | Module and Assembly with Dual DC-Links for Three-Level NPC Applications - A power semiconductor module has four power terminals. An IGBT has a collector connected to the first power terminal and an emitter coupled to the third power terminal. An anti-parallel diode is coupled in parallel with the IGBT. A DC-link is connected between the second and fourth power terminals. The DC-link may involve two diodes and two IGBTs, where the IGBTs are connected in a common collector configuration. The first and second power terminals are disposed in a first line along one side of the module, and the third and fourth power terminals are disposed in a second line along the opposite side of the module. Two identical instances of the module can be interconnected together to form a three-level NPC phase leg having low stray inductances, where the phase leg has two parallel DC-links. | 09-11-2014 |
20140246761 | FAST RECOVERY SWITCHING DIODE WITH CARRIER STORAGE AREA - A power device (such as a power diode) has a peripheral die area and a central area. The main PN junction of the device is formed by a P+ type region that extends down into an N− type layer. The central portion of the P+ type region has a plurality of openings so mesa structures of the underlying N− type material extend up to the semiconductor surface through the openings. Due to the mesa structures being located in the central portion of the die, there are vertically extending extensions of the PN junction in the central portion of the die. Minority carrier charge storage is more uniform per unit area across the surface of the die. Due to the form of the P+ type region and the mesa structures, the reverse recovery of the PN junction exhibits a soft characteristic. | 09-04-2014 |
20140183716 | SILVER-TO-SILVER BONDED IC PACKAGE HAVING TWO CERAMIC SUBSTRATES EXPOSED ON THE OUTSIDE OF THE PACKAGE - A packaged power device involves no soft solder and no wire bonds. The direct-bonded metal layers of two direct metal bonded ceramic substrate assemblies, such as Direct Bonded Aluminum (DBA) substrates, are provided with sintered silver pads. Silver nanoparticle paste is applied to pads on the frontside of a die and the paste is sintered to form silver pads. Silver formed by an evaporative process covers the backside of the die. The die is pressed between the two DBAs such that direct silver-to-silver bonds are formed between sintered silver pads on the frontside of the die and corresponding sintered silver pads of one of the DBAs, and such that a direct silver-to-silver bond is formed between the backside silver of the die and a sintered silver pad of the other DBA. After leadforming, leadtrimming and encapsulation, the finished device has exposed ceramic of both DBAs on outside package surfaces. | 07-03-2014 |
20140126258 | NON-ISOLATED AC-TO-DC CONVERTER HAVING A LOW CHARGING CURRENT INITIAL POWER UP MODE - In a steady state operation mode, a charging circuit of a non-isolated AC-to-DC converter decouples an output voltage V | 05-08-2014 |
20140119064 | LOW FORWARD VOLTAGE RECTIFIER - A Low Forward Voltage Rectifier (LFVR) includes a bipolar transistor, a parallel diode, and a base current injection circuit disposed in an easy-to-employ two-terminal package. In one example, the transistor is a Reverse Bipolar Junction Transistor (RBJT), the diode is a distributed diode, and the base current injection circuit is a current transformer. Under forward bias conditions (when the voltage from the first package terminal to the second package terminal is positive), the LFVR conducts current at a rated current level with a low forward voltage drop (for example, approximately 0.1 volts). In reverse bias conditions, the LFVR blocks current flow. Using the LFVR in place of a conventional silicon diode rectifier in the secondary of a flyback converter reduces average power dissipation and increases power supply efficiency. | 05-01-2014 |
20140118055 | IGBT DIE STRUCTURE WITH AUXILIARY P WELL TERMINAL - An IGBT die structure includes an auxiliary P well region. A terminal, that is not connected to any other IGBT terminal, is coupled to the auxiliary P well region. To accelerate IGBT turn on, a current is injected into the terminal during the turn on time. The injected current causes charge carriers to be injected into the N drift layer of the IGBT, thereby reducing turn on time. To accelerate IGBT turn off, charge carriers are removed from the N drift layer by drawing current out of the terminal. To reduce V | 05-01-2014 |
20140043878 | High-Efficiency, Low-Power Power Supply Circuit - A power supply circuit includes a rectifier, a charging circuit, and a storage capacitor. An AC signal is rectified by the rectifier thereby generating a rectified signal V | 02-13-2014 |
20140042624 | Power MOSFET Having Selectively Silvered Pads for Clip and Bond Wire Attach - A packaged power field effect transistor device includes a power field effect transistor die, a DBA substrate, a clip, a wire bond, leads, and an amount of plastic encapsulant. The top of the DBA has a plurality of metal plate islands. A sintered silver feature is disposed on one of the islands. A silvered backside of the die is directly bonded to the sintered silver structure of the DBA. The upper surface of the die includes a first aluminum pad (a source pad) and a second aluminum pad (a gate pad). A sintered silver structure is disposed on the first aluminum pad, but there is no sintered silver structure disposed on the second aluminum pad. A high current clip is attached via soft solder to the sintered silver structure on the first aluminum pad (the source pad). A bond wire is ultrasonically welded to the second aluminum pad (gate pad). | 02-13-2014 |
20130328204 | Solderless Die Attach to a Direct Bonded Aluminum Substrate - A DBA-based power device includes a DBA (Direct Bonded Aluminum) substrate. An amount of silver nanoparticle paste of a desired shape and size is deposited (for example by micro-jet deposition) onto a metal plate of the DBA. The paste is then sintered, thereby forming a sintered silver feature that is in electrical contact with an aluminum plate of the DBA. The DBA is bonded (for example, is ultrasonically welded) to a lead of a leadframe. Silver is deposited onto the wafer back side and the wafer is singulated into dice. In a solderless silver-to-silver die attach process, the silvered back side of a die is pressed down onto the sintered silver feature on the top side of the DBA. At an appropriate temperature and pressure, the silver of the die fuses to the sintered silver of the DBA. After wirebonding, encapsulation and lead trimming, the DBA-based power device is completed. | 12-12-2013 |
20130252381 | Electrically Isolated Power Semiconductor Package With Optimized Layout - A packaged power semiconductor device is provided with voltage isolation between a metal backside and terminals of the device. The packaged power semiconductor device is arranged in an encapsulant defining a hole for receiving a structure for physically coupling the device to an object. A direct-bonded copper (“DBC”) substrate is used to provide electrical isolation and improved thermal transfer from the device to a heatsink. At least one power semiconductor die is mounted to a first metal layer of the DBC substrate. The first metal layer spreads heat generated by the semiconductor die. In one embodiment, the packaged power semiconductor device conforms to a TO-247 outline and is capable of receiving a screw for physically coupling the device to a heatsink. | 09-26-2013 |
20130249529 | LOW FORWARD VOLTAGE RECTIFIER USING CAPACITIVE CURRENT SPLITTING - A Low Forward Voltage Rectifier (LFVR) circuit includes a bipolar transistor, a parallel diode, and a capacitive current splitting network. The LFVR circuit, when it is performing a rectifying function, conducts the forward current from a first node to a second node provided that the voltage from the first node to the second node is adequately positive. The capacitive current splitting network causes a portion of the forward current to be a base current of the bipolar transistor, thereby biasing the transistor so that the forward current experiences a low forward voltage drop across the transistor. The LFVR circuit sees use in as a rectifier in many different types of switching power converters, including in flyback, Cuk, SEPIC, boost, buck-boost, PFC, half-bridge resonant, and full-bridge resonant converters. Due to the low forward voltage drop across the LFVR, converter efficiency is improved. | 09-26-2013 |
20130217185 | POWER DEVICE MANUFACTURE ON THE RECESSED SIDE OF A THINNED WAFER - A recess is formed into a first side of a wafer such that a thinned center portion of the wafer is formed, and such that the central portion is surrounded by a thicker peripheral edge support portion. The second side of the wafer remains substantially entirely planar. After formation of the thinned wafer, vertical power devices are formed into the first side of the central portion of the wafer. Formation of the devices involves forming a plurality of diffusion regions into the first side of the thinned central portion. Metal electrodes are formed on the first and second sides, the peripheral portion is cut from the wafer, and the thin central portion is diced to form separate power devices. In one example, a first commercial entity manufactures the thinned wafers, and a second commercial entity obtains the thinned wafers and performs subsequent processing to form the vertical power devices. | 08-22-2013 |
20130175704 | DISCRETE POWER TRANSISTOR PACKAGE HAVING SOLDERLESS DBC TO LEADFRAME ATTACH - A packaged power transistor device includes a Direct-Bonded Copper (“DBC”) substrate. Contact pads of a first lead are attached with solderless welds to a metal layer of the DBC substrate. In a first example, the solderless welds are ultrasonic welds. In a second example, the solderless welds are laser welds. A single power transistor realized on a single semiconductor die is attached to the DBC substrate. In one example, a first bond pad of the die is wire bonded to a second lead, and a second bond pad of the die is wire bonded to a third lead. The die, the wire bonds, and the metal layer of the DBC substrate are covered with an amount of plastic encapsulant. Lead trimming is performed to separate the first, second and third leads from the remainder of a leadframe, the result being the packaged power transistor device. | 07-11-2013 |
20130128626 | Transformer Drive For Low Conduction Loss Rectifier In Flyback Converter - A flyback converter involves a bipolar transistor (BJT) and a parallel-connected diode as the rectifying element in the secondary side of the converter. The transformer of the converter has a primary winding, a first secondary winding, and a second secondary winding. A first end of the first secondary winding is coupled to the BJT base. A first end of the second secondary winding is coupled to the BJT collector and to the anode of the diode. The first and second secondary windings are wound such that when primary winding current stops, pulses of current flow out of the first ends of the first and second secondary windings. These currents are such that the BJT is maintained in saturation throughout at least most of the time current flows through the rectifying element, thereby achieving a low forward voltage across the rectifying element, reducing conduction loss, and increasing converter efficiency. | 05-23-2013 |
20130127017 | Bipolar Junction Transistor For Current Driven Synchronous Rectifier - A Reverse Bipolar Junction Transistor (RBJT) integrated circuit comprises a bipolar transistor and a parallel-coupled distributed diode. The bipolar transistor involves many N-type collector regions. Each N-type collector region has a central hole so that P-type material from an underlying P-type region extends up into the hole. A collector metal electrode covers the central hole forming a diode contact at the top of the hole. When the distributed diode conducts, current flows from the collector electrode, down through the many central holes in the many collector regions, through corresponding PN junctions, and to an emitter electrode disposed on the bottom side of the IC. The RBJT and distributed diode integrated circuit has emitter-to-collector and emitter-to-base reverse breakdown voltages exceeding twenty volts. The collector metal electrode is structured to contact the collector regions, and to bridge over the base electrode, resulting in a low collector-to-emitter voltage when the RBJT is on. | 05-23-2013 |
20130107583 | Low forward voltage rectifier | 05-02-2013 |
20130028338 | 1-Wire Communication Protocol and Interface Circuit for High Voltage Applications - A system for communicating with a host using control signals over a 1-wire interface is disclosed. The system includes a driver coupled to the host by the 1-wire interface. Control signals are transmitted from the host to the driver for decoding by the driver controller. The control signals are pulse width modulation format signals which are interpreted by the driver as binary encoded command mode signals or analog encoded command mode signals, depending upon when the signals are received in relation to a preamble pulse and a post-amble pulse. | 01-31-2013 |
20120168861 | POWER TRANSISTOR WITH INCREASED AVALANCHE CURRENT AND ENERGY RATING - A field-effect transistor involves a drain electrode, a drift region, a body region, a source region, a gate insulator layer, and a gate electrode. The drift region is disposed above the drain electrode. The body region extends down into the drift region from a first upper semiconductor surface. The source region is ladder-shaped and extends down in the body region from a second upper semiconductor surface. The first and second upper semiconductor surfaces are substantially planar and are not coplanar. A first portion of the body region is surrounded laterally by a second portion of the body region. The second portion of the body region and the drift region meet at a body-to-drift boundary. The body-to-drift boundary has a central portion that is non-planar. A gate insulator layer is disposed over the source region and a gate electrode is disposed over the gate insulator. | 07-05-2012 |
20110312137 | Vertical Power MOSFET and IGBT Fabrication Process with Two Fewer Photomasks - A process for fabrication of a power semiconductor device is disclosed in which a single photomask is used to define each of p-conductivity well regions and n-conductivity type source regions. In the process a single photomask is deposited on a layer of polysilicon on a wafer, the polysilicon layer is removed from first regions of the power semiconductor device where the p-conductivity well regions and the n-conductivity type source regions are to be formed, and both p-conductivity type and n-conductivity type dopants are introduced into the wafer through the first regions. | 12-22-2011 |
20110235271 | MOTHER AND DAUGHTER BOARD CONFIGURATION TO IMPROVE CURRENT AND VOLTAGE CAPABILITIES OF A POWER INSTRUMENT - An arrangement of a mother circuit board and daughter circuit boards in a power instrument improves current and voltage capabilities. A mother board is mounted to a base panel of an enclosure, and a number of daughter boards are attached to and extend from the mother board. Each daughter board has substantially identical circuitry and produces substantially the same amount of current. The daughter boards together provide a total output current equal to a sum of each individually generated current. The amount of power generated by the instrument can be increased by attaching additional daughter boards to the mother board. The total current produced by the daughter boards is provided to and output from the mother board via a low inductance output path. The low inductance output path ensures that a sudden increase in current does not result in a large voltage spike that adversely affects instrument operation. | 09-29-2011 |
20100307912 | METHODS AND APPARATUSES FOR CONVERTING CARBON DIOXIDE AND TREATING WASTE MATERIAL - Methods and apparatuses for converting carbon dioxide and treating waste material using a high energy electron beam are disclosed. For example, carbon dioxide and an aqueous reaction solution having a reactant can be combined to form an aqueous reaction mixture, and the aqueous reaction mixture can then be subjected to a high energy electron beam that initiates a reaction between carbon dioxide and the reactant to form a reaction product. Solid or liquid waste material can be treated by, for example, combining carbon dioxide and a solid or liquid waste material having a reactant and then subjecting the carbon dioxide and solid or liquid waste material having a reactant to a high energy electron beam to initiate a reaction between the carbon dioxide and the reactant to form a reaction product. | 12-09-2010 |
20100277104 | 1-WIRE COMMUNICATION PROTOCOL AND INTERFACE CIRCUIT - A 1-wire communication protocol and interface circuitry for communication between a host controller and a LED driver is provided. The 1-wire communication protocol is configured such that both PWM signals and DC current setting commands for programming the LED driver may be transmitted from the host controller to the LED driver via the same 1-wire interface. The 1-wire communication protocol uses the length of the pulses (pulse width), rather than the number of pulses, to distinguish between different modes of communication (PWM signal transmission mode or command pulse transmission mode) and different commands of the same type (specific DC current programming commands, or specific average PWM drive current for the LED, within each transmission mode). Because the same 1-wire interface is used for transmitting both PWM signals and DC current commands, integrated circuits for the host controller and the LED driver do not require an additional wire or pin. | 11-04-2010 |
20100224982 | LEAD AND LEAD FRAME FOR POWER PACKAGE - A power device includes a semiconductor chip provided over a substrate, and a patterned lead. The patterned lead includes a raised portion located between a main portion and an end portion. At least part of the raised portion is positioned over the semiconductor chip at a larger height than both the main portion and the end portion. A bonding pad may also be included. The end portion may include a raised portion, bonded portion, and connecting portion. At least part of the bonded portion is bonded to the bonding pad and at least part of the raised portion is positioned over the bonding pad at a larger height than the bonded portion and connecting portion. The end portion may also include a plurality of similarly raised portions. | 09-09-2010 |
20100109759 | SOLAR CELL DEVICE HAVING A CHARGE PUMP - A solar cell device includes a solar cell section configured to output a first voltage upon receiving light. A charge pump circuit includes a first charge pump. The first charge pump includes a first terminal and a second terminal. The first terminal is configured to receive the first voltage from the solar cell section, and the second terminal is configured to output a second voltage that is higher than the first voltage. An output section is configured to receive an output voltage output by the charge pump circuit. The charge pump circuit is formed on a single semiconductor substrate. | 05-06-2010 |
20100078674 | INSULATED GATE BIPOLAR TRANSISTOR - A trench structure of an insulated gate bipolar transistor (IGBT) is formed as a trench net in a P region and extends into an N− layer. The trench net separates the P region into P wells and floating P layers. The P wells contact an emitter electrode while the floating P layers are not in direct contact with the emitter electrode. A gate formed of conductive material and having a surrounding insulation oxide layer is formed in the trench net. An N+ layer may be formed above each floating P layer under the gate. The floating P layers are isolated from the gate and are also not connected to the emitter electrode. | 04-01-2010 |
20100042857 | SYSTEM AND METHOD FOR CONSERVING POWER APPLIED TO AN ELECTRICAL APPARATUS - A usage pattern identifies time periods when an electrical apparatus is likely to be powered-up or not in use. Power provided to an electrical apparatus is increased during time periods that the electrical apparatus is likely to be powered-up. Similarly, the power provided to the electrical apparatus is reduced or removed during time periods that the electrical apparatus is likely to be out of use or idle. The usage pattern is continually updated and refined by collecting usage data during user interaction with the electrical apparatus. | 02-18-2010 |
20090326597 | SOLAR CELL FOR IMPLANTABLE MEDICAL DEVICE - An implantable medical device includes a solar cell configured to provide energy to recharge a power source such as a battery. The power source is coupled to a control circuit of the medical device and provides power to the circuit. The solar cell may be coupled to the power source via a wire and may be distanced from a housing of the medical device. The solar cell may also be attached to the housing or may be disposed in the housing. The medical device may be implanted in the body of a host such that a surface of the solar cell is provided under a layer of skin of the host. The translucent property of skin allows the solar cell to receive light or infrared radiation from outside the body. The solar cell converts the received energy and provides the converted energy to the power source for recharging. | 12-31-2009 |