Class G audio amplifiers and associated methods of operation
Granted: December 10, 2013
Patent Number:
8605915
The present technology is directed to class G audio amplifiers and the associated methods of operation. In one embodiment, a class G audio amplifier includes an input port, an audio output stage, a level detector, and a charge pump. The class G audio amplifier regulates the power supplies of the audio output stage according to the input signal, so as to realize high efficiency and high quality audio output.
Multi-mode dimming circuit
Granted: December 10, 2013
Patent Number:
8604710
The present disclosure discloses a multi-mode dimming circuit configurable to operate in a first dimming mode, a second dimming mode and a third dimming mode. The present disclosure also discloses separate dimming circuits for respectively realize the three dimming modes. In one embodiment the multi-mode dimming circuit may comprise a first input terminal, a second input terminal, a third input terminal, an output terminal, a resistive device, an oscillation circuit and a pulse width…
Triac dimmer compatible WLED driving circuit and method thereof
Granted: December 3, 2013
Patent Number:
8598802
The present technology is generally related to Triac dimmer compatible driving circuits and methods thereof. The present technology also provides an electronic transformer that is integrated in the Traic dimmer compatible driving circuit. In one embodiment, the electronic transformer detects the conduction angles of an output AC voltage from the Triac dimmer and converts said output AC voltage into a PWM DC voltage having a duty cycle regulated by said conduction angles. Said PWM DC…
High voltage junction field effect transistor with spiral field plate
Granted: December 3, 2013
Patent Number:
8598637
In one embodiment, a junction field effect transistor having a substrate, wherein formed on the substrate is a graded n-doped region having a high doping concentration in an inner region and a low doping concentration in an outer region, with a p-doped buried region adjacent to the graded n-doped region near the outer region, and a spiral resistor connected to the graded n-doped region at its inner region and at its outer region. An ohmic contact at the inner region provides the drain,…
Compensation circuit for constant current regulation of power supply and method thereof
Granted: November 26, 2013
Patent Number:
8593841
A compensation circuit and method for constant current regulation of switching mode power supply are disclosed. The ringing waveform of a feedback signal, indicative of the output current of the power supply, causes error. To eliminate the error, a current source charges a capacitor in response to a demagnetizing oscillation signal indicative of the error caused by the ringing waveform of the feedback signal. The voltage across the capacitor is compared to a reference signal to generate…
Circuit and method for voltage regulator output voltage trimming
Granted: November 26, 2013
Patent Number:
8593121
The present disclosure discloses a voltage regulator including a trimming circuit. The present disclosure also discloses a method for trimming an output voltage of a voltage regulator. In one embodiment the voltage regulator may include a power conversion module, a feedback and trimming module and a control module. The voltage regulator may be able to provide an output voltage that could be regulated to a plurality of output values, the feedback and trimming module may be able to trim…
Internal high-voltage current source in an AC/DC power converter
Granted: November 19, 2013
Patent Number:
8587973
AC/DC power converters having an under voltage lockout circuit with first and second thresholds and associated methods of operation are disclosed herein. In one embodiment, the first threshold is greater than the second threshold. The under voltage lockout circuit is configured to enable a current source to charge the capacitor when the voltage across the capacitor is less than the second threshold. The under voltage lockout circuit is configured to shut off the current source and to…
Triac dimmer compatible switching mode power supply and method thereof
Granted: November 12, 2013
Patent Number:
8581518
Triac dimmer compatible switching mode power supplies used as LED drivers are disclosed herein. A PFC controller is configured in the switching mode power supplies. With the PFC controller, the current keeping the triac in the on-state is supplied by the DC/DC converter, and the LC resonance is reduced.
Bipolar junction transistor with layout controlled base and associated methods of manufacturing
Granted: November 12, 2013
Patent Number:
8581365
The present technology discloses a bipolar junction transistor (BJT) device integrated into a semiconductor substrate. The BJT device comprises a collector, a base and an emitter. The collector is of a first doping type on the substrate; the base is of a second doping type in the collector from the top surface of the semiconductor device and the base has a base depth; and the emitter is of a first doping type in the base from the top surface of the semiconductor device. The base depth is…
Switching mode power supply with primary side control
Granted: November 5, 2013
Patent Number:
8576588
The present technology are directed to switching mode power supplies with primary side control. In one embodiment, the switching mode power supply provides an equivalent current signal which represents a load current. The equivalent current signal is then used to control a switching circuit in the switching mode power supply.
High density lateral DMOS with recessed source contact
Granted: October 1, 2013
Patent Number:
8546879
The present disclosure discloses a lateral DMOS with recessed source contact and method for making the same. The lateral DMOS comprises a recessed source contact which has a portion recessed into a source region to reach a body region of the lateral DMOS. The lateral DMOS according to various embodiments of the present invention may have greatly reduced size and may be cost saving for fabrication.
Low loss discharge circuits for EMI filter capacitors
Granted: September 24, 2013
Patent Number:
8541987
A discharge circuit for an EMI filter capacitor includes normally-ON transistors. The normally-ON transistors may be controlled to limit current through them when an AC source is coupled across the discharge circuit. When the AC source is disconnected from the discharge circuit, the normally-ON transistors turn ON to allow current flow through them. The current flow allows the EMI filter capacitor to be discharged by a discharge resistor.
Latch-off of synchronous rectification for light load control
Granted: September 17, 2013
Patent Number:
8537584
Disclosed is a light load control circuit and the method accordingly where the synchronous rectification is latched off when the light load condition is detected for several successive cycles.
Average input current limit method and apparatus thereof
Granted: September 3, 2013
Patent Number:
8525498
The embodiment of invention discloses an average input current limit method and apparatus thereof. The apparatus comprises a switching circuit, a current average circuit and a current limit circuit. The current average circuit samples the input current of the switching circuit and generates a signal representative of the average value of the input current. The current limit circuit limits the signal so as to limit the average value of the input current.
Circuitry for driving light emitting diodes and associated methods
Granted: September 3, 2013
Patent Number:
8525423
Circuitry and methods for driving a plurality of LED strings are disclosed herein. In one embodiment, the circuitry comprises a plurality of current regulating circuits electrically coupled to the LED strings and are configured to regulate a current flowing through the LED strings. At least two control circuits are coupled to the current regulating circuits and are configured to generate a control signal according to terminal voltages of the corresponding current regulating circuits. A…
Super junction device with deep trench and implant
Granted: September 3, 2013
Patent Number:
8525260
RESURF effect devices with both relatively deep trenches and relatively deep implants are described herein. Also, methods of fabricating such devices are described herein. A RESURF effect device may include alternating regions of first and second conductivity types where each of the second regions includes an implant region formed into a trench region of the second region.
High power-supply rejection ratio amplifying circuit
Granted: August 20, 2013
Patent Number:
8514024
The embodiments of the present invention disclose a high power-supply rejection ratio (PSRR) amplifier circuit. The amplifier circuit comprises a low dropout regulator, a negative charge pump and an amplifier. The output voltages of the negative charge pump and the low dropout regulators don't track the change of input voltage. Therefore the amplifier circuit has high PSRR.
DC brushless motor system and the method thereof
Granted: August 6, 2013
Patent Number:
8502486
A DC brushless motor system is disclosed. When a rotor of the DC brushless motor is close to an aligned position, there will be current spike in the coil and voltage spike in an input capacitor. By decreasing the peak current limit of the current in the coil when the rotor is close to the aligned position, the current spike and the voltage spike are reduced.
High dimming ratio control and short circuit protection for LED drive with step up converter
Granted: August 6, 2013
Patent Number:
8503139
The present invention discloses a step up circuit with output floating for driving a load such as a LED or a series of LEDs in a string. The step up circuit comprises an input port, an output port, an inductor, an input capacitor, an output capacitor, a first switch, a second switch and a third switch. The third switch S3 is an additional switch for purpose of high dimming ratio control, short circuit protection and input disconnection realization. Further, the third switch can implement…
Switching mode power supply with predicted PWM control
Granted: August 6, 2013
Patent Number:
8502510
The present technology discloses a switching mode power supply with predicted PWM control. In one embodiment, the switching mode power supply monitors the slew rate of COMP signal which represents the output voltage of the switching mode power supply. When the load steps up, the ON state of the power stage is prolonged; when the load steps down, the power stage is turned off earlier.
