IXYS Patent Applications

SILVER-TO-SILVER BONDED IC PACKAGE HAVING TWO CERAMIC SUBSTRATES EXPOSED ON THE OUTSIDE OF THE PACKAGE

Granted: July 3, 2014
Application Number: 20140183716
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…

NON-ISOLATED AC-TO-DC CONVERTER HAVING A LOW CHARGING CURRENT INITIAL POWER UP MODE

Granted: May 8, 2014
Application Number: 20140126258
In a steady state operation mode, a charging circuit of a non-isolated AC-to-DC converter decouples an output voltage VO node from a VR node when the rectifier output signal VR on the VR node is greater than a first predetermined voltage VP and, 2) supplies a charging current from the VR node and onto the VO node when VR is less than VP provided that an output voltage VO on the VO node is less than a second predetermined voltage VO(MAX) and provided that VR is greater than VO. In an…

LOW FORWARD VOLTAGE RECTIFIER

Granted: May 1, 2014
Application Number: 20140119064
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…

IGBT DIE STRUCTURE WITH AUXILIARY P WELL TERMINAL

Granted: May 1, 2014
Application Number: 20140118055
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…

Recovering Energy From An IrDA/Remote Control Transmitter Circuit

Granted: February 20, 2014
Application Number: 20140049183
A portable electronic device with an IrDA transmitter LED is used to transmit both IrDA signals and remote control infrared signals. The device transmits remote control infrared signals with reduced power consumption. During a relatively longer remote control signal pulse, an inductor saturates and stores energy when a drive current flows from a power supply, through the inductor and then through the LED. An energy-transferring circuit transfers a portion of the energy stored in the…

High-Efficiency, Low-Power Power Supply Circuit

Granted: February 13, 2014
Application Number: 20140043878
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 VR between a VR node and a GND node. The capacitor is coupled between an output voltage VO node and the GND node. If VR is greater than a first predetermined voltage VP then the VO node is decoupled from the VR node. If VR is below VP then the charging circuit supplies a substantially constant charging current from the…

Power MOSFET Having Selectively Silvered Pads for Clip and Bond Wire Attach

Granted: February 13, 2014
Application Number: 20140042624
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…

Solderless Die Attach to a Direct Bonded Aluminum Substrate

Granted: December 12, 2013
Application Number: 20130328204
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…

LOW FORWARD VOLTAGE RECTIFIER USING CAPACITIVE CURRENT SPLITTING

Granted: September 26, 2013
Application Number: 20130249529
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…

Electrically Isolated Power Semiconductor Package With Optimized Layout

Granted: September 26, 2013
Application Number: 20130252381
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…

POWER DEVICE MANUFACTURE ON THE RECESSED SIDE OF A THINNED WAFER

Granted: August 22, 2013
Application Number: 20130217185
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…

DISCRETE POWER TRANSISTOR PACKAGE HAVING SOLDERLESS DBC TO LEADFRAME ATTACH

Granted: July 11, 2013
Application Number: 20130175704
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,…

Transformer Drive For Low Conduction Loss Rectifier In Flyback Converter

Granted: May 23, 2013
Application Number: 20130128626
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…

Sample and Hold Time Stamp for Sensing Zero Crossing of Back Electromotive Force in 3-Phase Brushless DC Motors

Granted: May 23, 2013
Application Number: 20130127385
A microcontroller determines the position of the rotor of a brushless, direct-current motor by determining the time of zero crossing of back electromotive force (EMF) emanating from the non-driven phase winding. The zero crossing point is determined by interpolating voltage differentials that are time stamped. Each voltage differential is the difference between the phase voltage of the phase winding and the motor neutral point voltage. The time of zero crossing is determined without…

Bipolar Junction Transistor For Current Driven Synchronous Rectifier

Granted: May 23, 2013
Application Number: 20130127017
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…

1-Wire Communication Protocol and Interface Circuit for High Voltage Applications

Granted: January 31, 2013
Application Number: 20130028338
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…

Power Semiconductor Module with Asymmetrical Lead Spacing

Granted: January 24, 2013
Application Number: 20130021759
A power semiconductor has power terminals arranged in a row at one side of the housing, with control terminals arranged in a row at the other side of the housing. The spacing between adjacent power terminals is greater than the spacing between adjacent control terminals.

Method of Joining Metal-Ceramic Substrates to Metal Bodies

Granted: December 6, 2012
Application Number: 20120305281
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 aluminium 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…

Open-Loop Transimpedance Amplifier for Infrared Diodes

Granted: December 6, 2012
Application Number: 20120306577
A microcontroller integrated circuit includes an open-loop transimpedance amplifier (OLTA). An input lead of the OLTA is a terminal of the microcontroller. The cathode of a photodiode is connected to VDD and the anode is connected to the terminal. The OLTA maintains the photodiode in a strongly reverse-biased condition, thereby keeping diode capacitance low and facilitating rapid circuit response. The input of the OLTA involves a diode-connected field effect transistor that provides a…

Low-Cost Magnetic Stripe Reader Using Independent Switching Thresholds

Granted: September 20, 2012
Application Number: 20120235740
A F/2F waveform generator has a comparator and an analog multiplexer. In a low-cost magnetic card reader application, a magnetic track signal is amplified, filtered, and compared with a threshold signal to create a digital signal output. The analog multiplexer detects changes in state of the digital signal. When a change of state is detected, the analog multiplexer switches among dynamically tunable threshold signals. The selected threshold signal is used for comparison with the magnetic…