IXYS Patent Grants

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…

Multi-stage LED driver with current proportional to rectified input voltage and low distortion

Granted: January 10, 2017
Patent Number: 9544961
A system for driving a multi-stage LED with low distortion and with current proportional to rectified input voltage is disclosed. In an exemplary embodiment, an apparatus includes LED groups connected in series to form an LED string having a first node, a last node, and intermediate nodes. The apparatus also includes current cells having inputs coupled to the nodes and outputs coupled to an output resistor. Each current cell selectively regulates current to flow between its respective…

Chopper stabilized amplifier with synchronous switched capacitor noise filtering

Granted: October 18, 2016
Patent Number: 9473074
A chopper stabilized 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 device module

Granted: September 13, 2016
Patent Number: 9443792
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…

Blank bit and processor instructions employing the blank bit

Granted: September 6, 2016
Patent Number: 9436466
Reading a value into a register, checking to see if the value is a NULL, and then jumping out of a loop if the value is a NULL is a common task that processors perform. To speed performance of such a task, a novel “blank bit” is added to the flag register of a processor. When a first instruction (arithmetic, logic or load) is executed, the instruction operands are checked to see if any is a NULL character value. Information on the result of the check is stored in the blank bit.…

Dimming a multi-lamp fluorescent light fixture by turning off an individual lamp using a wireless fluorescent lamp starter

Granted: August 30, 2016
Patent Number: 9433067
A multi-lamp fluorescent light fixture includes a plurality of replaceable fluorescent lamp starter units. Each starter unit has a built-in microcontroller, an RF (Radio-Frequency) receiver, and communicates wirelessly with a master unit. The plurality of starter units can be wirelessly controlled to dim the multi-lamp fixture. Each starter unit receives a DIM command. Each starter unit identified as a dimmer starter unit responds to the DIM command by turning off coupled fluorescent…

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

Granted: August 16, 2016
Patent Number: 9419118
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…

Ultra-fast breakover diode

Granted: June 28, 2016
Patent Number: 9379203
An ultra-fast breakover diode has a turn on time TON that is less than 0.3 microseconds, where the forward breakover voltage is greater than +400 volts and varies less than one percent per ten degrees Celsius change. In another aspect of the invention, a breakover diode has a reverse breakdown voltage that is greater, in absolute magnitude, than the forward breakover voltage, where the forward breakover voltage is greater than +400 volts. Yet another aspect of the invention involves a…

Video and content controlled backlight

Granted: May 31, 2016
Patent Number: 9355580
A display device includes a display panel; and a backlight panel provided below the display panel and defining a plurality of regions. A first array of light emitting diodes (LEDs) is provided along a first direction, each LED of the first array being coupled to a first line. A driver is coupled to the first line to drive the LEDs coupled to the first line. A second array of LEDs is provided along a second direction, each LEDs of the second array being coupled to a second line. A…

Low forward voltage rectifier

Granted: May 24, 2016
Patent Number: 9350254
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…

Full bridge rectifier module

Granted: May 10, 2016
Patent Number: 9337171
A full bridge rectifier includes four bipolar transistors, each of which has an associated parallel diode. A first pair of inductors provides inductive current splitting and thereby provides base current to/from one pair of the bipolar transistors so that the collector-to-emitter voltages of the bipolar transistors are low. A second pair of inductors similarly provides inductive current splitting to provide base current to/from the other pair of bipolar transistors. In one embodiment,…

Bias current control of laser diode instrument to reduce power consumption of the instrument

Granted: May 10, 2016
Patent Number: 9337616
Embodiments for driving a laser diode includes generating a bias current having a duty cycle that is less than 100%. The current level of the bias current is insufficient to turn on the laser diode. A drive current is generated and combined with the bias current to turn on the laser diode almost instantly.

Efficient inrush current control in power factor corrected AC-to-DC converter

Granted: May 10, 2016
Patent Number: 9337744
An AC-to-DC converter involves a rectifier, an inductor, a storage capacitor, a switch, and a microcontroller. In a capacitor pre-charge operation, the periodicity and voltage amplitude of an AC supply voltage are determined. Based on this, the microcontroller identifies one of a plurality of stored sequences. Each sequence is a list of values. The microcontroller turns off the switch on AC supply voltage zero crossings and turns on the switch in accordance with the values. As a result,…

Bit-flipping memory controller to prevent SRAM data remanence

Granted: April 26, 2016
Patent Number: 9324072
A memory is organized into blocks. In a bit-flipping operation, a memory block is read, the read bit data values are inverted, and the inverted data is written back to the memory block. Inverted memory blocks are tracked by setting a flag bit in the memory block, or by storing a pointer to a memory block. In a read operation, a memory block is read and, if the tracking method indicates the memory block is inverted, the read data values are reverted before being returned. In a write…

Recovering energy from an IrDA/remote control transmitter circuit

Granted: March 15, 2016
Patent Number: 9287985
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…

Turning off multiple fluorescent lamps simultaneously using RF-enabled lamp starter units

Granted: March 15, 2016
Patent Number: 9288874
A multi-lamp fluorescent light fixture includes a plurality of replaceable fluorescent lamp starter units. Each starter unit has a built-in microcontroller, an RF (Radio-Frequency) receiver, and communicates wirelessly with a master unit. Each starter unit can be wirelessly controlled to turn off coupled fluorescent lamps. Each starter unit receives a turn off command, monitors the AC voltage supplied to coupled lamps, and initiates turn off when the AC voltage reaches a threshold…

Photovoltaic cell and E-ink display on the front side of a cell phone case

Granted: March 1, 2016
Patent Number: 9276628
A cellular telephone case has front and back panels. A cellular telephone is coupled to the case by pushing the telephone into the case such that the main dock connector of the telephone engages a plug on the back panel. When the telephone is in this position, a back surface of the telephone is held in place on an inside surface of the back panel. The front panel is hinged so that it folds over and covers the telephone. In this folded position, the upward and outward facing outside…

Forward converter with self-driven BJT synchronous rectifier

Granted: February 16, 2016
Patent Number: 9263959
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…

High-efficiency, low-power power supply circuit

Granted: December 29, 2015
Patent Number: 9225260
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…