Abstract: An LED lamp has two preheating current control units respectively connected to a first electrode terminal and a second electrode terminal of the LED lamp, two lamp-side rectification circuits, and an LED light string. Each preheating current control unit has a ballast-side rectification circuit connected to one of the first and second electrode terminals and a load-varying circuit having a resistive load and a control circuit. The resistive load is serially connected to a DC output terminal of the ballast-side rectification circuit through the control circuit. The control circuit adjusts a resistance of the resistive load. Two input terminals of each lamp-side rectification circuit are respectively connected to one of the electrodes of each of the first electrode terminal and the second electrode terminal. The LED light string has two ends respectively connected to the two output terminals of each lamp-side rectification circuit, and has multiple series-connected LED elements.

Abstract: An arrester includes a switch and a lightning detection breaker connected to the switch. The lightning detection breaker includes a metal conducting terminal electrically connected to an earth return, a DC power supply terminal, a ground terminal and an output terminal. When the power supply is under a lightning strike, a potential difference of both the DC power supply terminal and the ground terminal of the lightning detection breaker will go up to several thousands of volts. However, a voltage of the metal conducting terminal will not go up because the metal conducting terminal is electrically connected to the earth return. The switch will automatically become open circuit by the lightning detection breaker, and therefore an electronic device connected to the arrester is protected from damage done by the lightning.

Abstract: The LED lighting tube compatible with an electronic ballast has two snubber circuits, a waveform conversion circuit, and at least one LED light string. The snubber circuits are connected to terminals of the LED lighting tube, and input terminals of each snubber circuit are connected to electrode pins of a corresponding terminal. Each snubber circuit has at least one resistor connected in series between the electrode pins of the corresponding terminal. The waveform conversion circuit has multiple rectifier diodes, and input terminals of the waveform conversion circuit are respectively connected to output terminals of the snubber circuits, with a recovery time of each rectifier diode being under 2.5 us. Two ends of the at least one LED light string are respectively connected to output terminals of the waveform conversion circuit, and each one of the at least one LED light string includes multiple LED units connected in series.

Abstract: An LED lamp has two preheating current control units respectively connected to a first electrode terminal and a second electrode terminal of the LED lamp, two lamp-side rectification circuits, and an LED light string. Each preheating current control unit has a ballast-side rectification circuit connected to one of the first and second electrode terminals and a load-varying circuit having a resistive load and a control circuit. The resistive load is serially connected to a DC output terminal of the ballast-side rectification circuit through the control circuit. The control circuit adjusts a resistance of the resistive load. Two input terminals of each lamp-side rectification circuit are respectively connected to one of the electrodes of each of the first electrode terminal and the second electrode terminal. The LED light string has two ends respectively connected to the two output terminals of each lamp-side rectification circuit, and has multiple series-connected LED elements.

Abstract: The LED lighting tube that is compatible with an electronic ballast has two snubber circuits, a waveform conversion circuit, and at least one LED light string. The snubber circuits are connected to terminals of the LED lighting tube, and input terminals of each snubber circuit are connected to electrode pins of a corresponding terminal, and each snubber circuit has at least one resistor connected in series between the electrode pins of the corresponding terminal. The waveform conversion circuit has multiple rectifier diodes, wherein input terminals of the waveform conversion circuit are respectively connected to output terminals of the snubber circuits, wherein a recovery time of each rectifier diode is under 2.5 us. Two ends of the at least one LED light string are respectively connected to output terminals of the waveform conversion circuit, wherein each one of the at least one LED light string comprises multiple LED units connected in series.

Abstract: The LED light tube compatible with a light fixture having an ballast has a translucent tube and an LED light bar mounted in the translucent tube. and having at least one waveform conversion circuit having multiple rectifier diodes and at least one LED light string connected to the at least one waveform conversion circuit, wherein a recovery time of each rectifier diode is under 1 ?s; the ballast determines the at least one waveform conversion circuit and the at least one LED light string as low impedance loads, thus, the ballast does not output a high voltage AC power and burn the LED light tube; a recovery time of each rectifier diode is also short such that the LED light tube can endure a high frequency AC power outputted by the ballast. As such, the LED light tube is compatible with the light fixture.

Abstract: A sense amplifier comprising a reference current developed from a programmed and a non-programmed reference cell is used to read a signal from a magnetic random access memory (MRAM) comprising magnetic tunnel junction (MTJ) cells. The average current is determined from reference cells in as few as one sense amplifier and as many as n sense amplifiers, and is an average current between the programmed reference cell and the non-programmed reference cell that approximates the mid point between the two states. The sense amplifier can be fully differential or a non differential sense amplifier.

Abstract: A linear light-emitting diode (LED) driving circuit with voltage-lowering serial capacitor has a rectification unit, an LED unit, a constant current controller, a series and parallel voltage divider and a controller. The controller is built in with a safe voltage threshold, controls the series and parallel voltage divider to be connected in series to the LED unit when an output voltage of the rectification unit exceeds the safe voltage threshold, ensuring that an average voltage across the LED unit and the constant current controller is stable, and controls the series and parallel voltage divider to be parallelly connected across the LED unit and the ground when the output voltage of the rectification unit does not exceed the safe voltage threshold. Accordingly, a safety standard of voltage for LED driving circuit can be secured and users' safety can be ensured.

Abstract: A high-voltage driver integratable with an integrated circuit has a switching transistor, a switching diode, a first resistor, a second resistor, and a control transistor. The anode of the switching diode is connected to the source of the switching transistor. The cathode of the switching diode is connected to the gate of the switching transistor. When the source voltage of the switching transistor is far greater than the cut-in voltage of the switching diode, the switching diode is forward-biased, and the gate-source voltage of the switching transistor is equal to the negative cut-in voltage. Accordingly, high voltage will not be generated across the gate-source junction of the switching transistor, no junction breakdown will occur between the gate and source thereof, and the high-voltage driver can be integrated with an integrated circuit.

Abstract: A high efficiency AC LED driver circuit has a rectifier unit, an LED light string, multiple voltage controlled transistors, a current detection unit, and a power efficiency control unit. The rectifier unit is connected to an AC power and converts the AC power into a pulsating DC power. The LED light string is connected to the rectifier unit and has multiple LED units. The voltage controlled transistors are respectively and electrically connected to each LED unit and form multiple shunt circuits. The current detection unit is electrically connected to the voltage controlled transistors. The power efficiency control unit is electrically connected to the current detection unit, series nodes between the LED units and the control terminals of the voltage controlled transistors; wherein the power efficiency control unit adjusts loop current based on a voltage drop of each LED unit.

Abstract: The flicker-free linear LED driver circuit with high power factor has a rectifier unit, an LED unit, a constant current unit, a storage capacitor and a voltage controlled transistor; the rectifier unit is connected to an AC power and converts the AC power into a pulsating DC power; the LED unit is connected to the rectifier unit and has multiple LED sources; the constant current unit is connected in series with the LED unit to form a first power circuit; wherein current flowing in the LED unit is fixed to a constant value by the constant current unit; the storage capacitor is connected to the rectifier unit; the voltage controlled transistor is connected in series with the storage capacitor to form a second power circuit; wherein the voltage controlled transistor limits current flowing in the storage capacitor under a maximum current limit value.

Abstract: Systems and methods for realizing reference currents to improve reliability of sensing operations of segmented semiconductor memory arrays have been achieved. Preferred embodiments of the invention comprise MRAM arrays but the invention could be applied to any other memories requiring access on small, segmented arrays. All embodiments of the invention comprise a folded bit lines scheme, either in adjacent bit lines or in segment-to-segment folded bit lines. In two embodiments alternate strapping of Poly-Si Word Lines in every second segment is achieved by metal layer of Read Word Line and Write Select Line. An embodiment has stored 1 and 0 cells on both sides of a selected segment to be read.

Abstract: A sense amplifier comprising a reference current developed from a programmed and a non-programmed reference cell is used to read a signal from a magnetic random access memory (MRAM) comprising magnetic tunnel junction (MTJ) cells. The average current is determined from reference cells in as few as one sense amplifier and as many as n sense amplifiers, and is an average current between the programmed reference cell and the non-programmed reference cell that approximates the mid point between the two states. The sense amplifier can be fully differential or a non differential sense amplifier.

Abstract: Systems and methods for realizing current drivers without current or voltage feedback for devices that require accurate current drive with zero standby current has been disclosed. In a preferred embodiment of the invention this current driver is applied for write circuits for MRAMs. A fast and accurate reference current is generated by diode voltage divided by resistor without any feedback. The diode current is not fed back from the reference current. The diode current is generated from a regulated voltage. Temperature compensation of the write current is inherently built in the diode current reference. Fine-tuning of the temperature coefficient is achieved by mixing poly and diffusion resistors. A switch inserted in the current driver can turn on the driver fast and without a need for standby current. Leading boost in the current driver can fast charge the large coupling capacitance of word and bit lines and speed up write timing.

Abstract: Systems and methods for realizing reference currents to improve reliability of sensing operations of segmented semiconductor memory arrays have been achieved. Preferred embodiments of the invention comprise MRAM arrays but the invention could be applied to any other memories requiring access on small, segmented arrays. All embodiments of the invention comprise a folded bit lines scheme, either in adjacent bit lines or in segment-to-segment folded bit lines. In two embodiments alternate strapping of Poly-Si Word Lines in every second segment is achieved by metal layer of Read Word Line and Write Select Line. An embodiment has stored 1 and 0 cells on both sides of a selected segment to be read.

Abstract: Systems and methods for realizing current drivers without current or voltage feedback for devices that require accurate current drive with zero standby current has been disclosed. In a preferred embodiment of the invention this current driver is applied for write circuits for MRAMs. A fast and accurate reference current is generated by diode voltage divided by resistor without any feedback. The diode current is not fed back from the reference current. The diode current is generated from a regulated voltage. Temperature compensation of the write current is inherently built in the diode current reference. Fine-tuning of the temperature coefficient is achieved by mixing poly and diffusion resistors. A switch inserted in the current driver can turn on the driver fast and without a need for standby current. Leading boost in the current driver can fast charge the large coupling capacitance of word and bit lines and speed up write timing.

Abstract: Voltage and current stress for magnetic random access memory (MRAM) cells can weed out potential early failure cells. Method and circuit implementation of such a stress test for a MRAM comprise coupling a stress test circuit to the read bus of the MRAM and stressing the Magnetic Tunnel Junctions (MTJS) by tying them to ground by activating isolation transistors associated with them. Read word lines control which MTJs are stressed Both the method and implementation can be used for any memory cells based on resistance differences, such as Phase RAM or Spin Valve MRAM.

Abstract: Voltage and current stress for magnetic random access memory (MRAM) cells can weed out potential early failure cells. Method and circuit implementation of such a stress test for a MRAM comprise coupling a stress test circuit to the read bus of the MRAM and stressing the Magnetic Tunnel Junctions (MTJS) by tying them to ground by activating isolation transistors associated with them. Read word lines control which MTJs are stressed Both the method and implementation can be used for any memory cells based on resistance differences, such as Phase RAM or Spin Valve MRAM.

Abstract: A buffered nondestructive-readout Josephson memory cell comprises only three gates and is free of the half-select problem associated with Josephson memories, for both write and read operations. The basic memory cell unit comprises a first interferometer gate and an associated inductor defining a memory storage loop and a second interferometer gate that, together with a second inductor, defines a second loop in which a current pulse can be established only when a circulating current exists in the first loop. A third gate, responsive to a sense line and to the current pulse in the second loop, provides a voltage output which changes based upon whether a "1" or a "0" has been stored in the storage loop. For fabricating a bit-accessible memory, the third gate is further connected in closed circuit relationship with a third inductor which is magnetically coupled with the first gate.

Abstract: An optically pumped semiconductor laser comprises multiple asymmetric quantum well structures. Using the structures described herein, the selection rules for additional optical transitions can be made possible and three or four level lasers can be obtained. A population inversion can be achieved by optical pumping for lasing for those not allowed in a simple quantum well.