Accurate current limit for peak current mode DC-DC converter
Granted: March 20, 2012
Patent Number:
8138734
A DC-DC converter includes a switching stage and a control circuit coupled to provide an accurate current limit for peak current mode for the DC-DC converter. The control circuit is operative to provide a peak value of the peak current mode.
Method and apparatus for driving multiple parallel discharge lamps
Granted: February 14, 2012
Patent Number:
8115402
The present invention provides a method and apparatus for driving multiple parallel discharge lamps, which increases the switching frequency once the open lamp condition is detected to provide an output voltage that is high enough to ignite the lamp again.
Method and circuit for short-circuit and over-current protection in a discharge lamp system
Granted: January 24, 2012
Patent Number:
8102129
Embodiments of the present technology provide short-circuit detection and protection suitable for a discharge lamp system. In several embodiments, the transformer's primary current is sensed and used to provide short-circuit protection of the secondary winding side or high voltage side.
Smart driving method for synchronous rectifier and its apparatus thereof
Granted: January 24, 2012
Patent Number:
8102680
The present invention discloses a smart driving method for a secondary synchronous rectifier of an isolated converter and its apparatus thereof. The apparatus comprises: a main circuit having a secondary synchronous rectifier Q1; a differentiation filter circuit, filtering the drain-source voltage Vds of the secondary synchronous rectifier, comprising a capacitor and at least one resistor connected in series and outputting a filtered voltage Vf from either between said capacitor and said…
Pulse dimming circuit and the method thereof
Granted: January 17, 2012
Patent Number:
8098018
The present invention provides a pulse dimming circuit and a method thereof. The pulse dimming circuit is compatible for both DC input signal and PWM input signal using only one circuit board, and includes a first input port, a second input port, a comparison signal generator, a comparator, a logic module, and a switch network electrically coupled to the second input port, an output terminal of the comparator, and an output terminal of the logic module.
Power devices with super junctions and associated methods manufacturing
Granted: December 27, 2011
Patent Number:
8084811
Power devices with super junctions and associated methods of manufacturing are disclosed herein. In one embodiment, a method for forming a power device includes forming an epitaxial layer on a substrate material and forming a trench in the epitaxial layer. The trench has a first sidewall, a second sidewall, and a bottom between the first and second sidewalls. The method also includes forming an insulation material on at least one of the first and second sidewalls of the trench and…
Short circuit current ratcheting in switch mode DC/DC voltage regulators
Granted: December 27, 2011
Patent Number:
8085025
A regulator with a high side pass device and a low side pass device coupled in series to the high side pass device is disclosed. The apparatus further includes a control module coupled to the high side pass device and the low side pass device. The control module is coupled to the high side pass device and the low side pass device to control the high side pass device and the low side pass device. The control module is operable to lock out the high side pass device under certain…
Method and apparatus for high performance switch mode voltage regulators
Granted: December 20, 2011
Patent Number:
8080985
Circuit configurations for a high power switch-mode voltage regulator circuit is disclosed that include an array of Metal Oxide Semiconductor (MOS) switching transistors electrically coupled to one another at their drains and sources and a plurality of gate driver circuits. Each gate driver circuit is coupled to a gate and dedicated to driving only one MOS switching transistor.
Input surge protection device using JFET
Granted: November 29, 2011
Patent Number:
8068321
An input surge suppression device and method that uses a simple JFET structure. The JFET has its gate clamped to a predetermined value, its the drain receives the input voltage from an input power source, its source is connected to the input of a down-stream device, and a resistor connected between the drain and the gate or between the source and the gate. Thus, when the drain voltage approximates the clamped gate voltage, the source voltage nearly equals the drain voltage. When the…
High bandwidth, rail-to-rail differential amplifier with intermediate stage current amplifier
Granted: November 29, 2011
Patent Number:
8067983
An error amplifier expected to exhibit rail-to-rail operation, high bandwidth, and high slew rate, is described, the error amplifier comprising a first stage to receive an input differential voltage and to provide transconductance gain, an intermediate stage to provide current gain, and an output stage to drive a load.
Driver for a flyback converter using a transconductance amplifier and a comparator
Granted: November 29, 2011
Patent Number:
8067973
The present invention discloses a smart driver used in flyback converters adopting a transconductance amplifier to turn on a synchronous rectifier FET, and a comparator to quickly turn off the synchronous rectifier FET.
Simple protection circuit and adaptive frequency sweeping method for CCFL inverter
Granted: November 22, 2011
Patent Number:
8063570
A CCFL inverter circuit integrates a feedback circuit and protection circuit together. For both in-phase and out-of-phase applications, sensed lamp voltages can be used for open lamp and short lamp detection and sensed currents can be used for open lamp detection. The driving circuit adjusts the open lamp frequency by using a duty cycle control signal so that the driving circuit can always achieve the desired lamp voltage gain.
Sandwich structure with double-sided cooling and EMI shielding
Granted: November 22, 2011
Patent Number:
8064202
A sandwich structure and method thereof is disclosed for double-sided cooling, EMI noise shielding and current carrying in mini-modules. The proposed structure comprises a top structure and a bottom structure to achieve double-sided cooling. Meanwhile, the top structure is configured to shield EMI noises as well. The proposed structure further comprises a first set of connecting structures for connecting devices of the mini-modules with the top structure and a second set of connecting…
Pulse frequency modulation methods and circuits
Granted: November 15, 2011
Patent Number:
8058859
A technique for voltage regulation involves switching between light load mode and PWM mode based on load conditions. Advantageously, this improves efficiency at light load. In an embodiment, error amplifier output is used to determine whether load is light. When light load is detected, extend PWM off time until the output voltage reaches a load threshold.
Charge pump for switched capacitor circuits with slew-rate control of in-rush current
Granted: November 1, 2011
Patent Number:
8049551
A ramp-up circuit for switched capacitor circuits with negative feedback to control the slew rate of in-rush current. Other embodiments are described and claimed.
Close-loop class-D audio amplifier and control method thereof
Granted: October 18, 2011
Patent Number:
RE42846
The present invention discloses a Class-D power amplifier and control method thereof. In one embodiment, the amplifier feeds back the signal at the output node to the inverting input of the comparator, and provides a high frequency triangular wave signal to the non-inverting input of the comparator. In addition, the non-inverting input of the comparator may be coupled to an offset voltage, while the inverting input of the comparator may be coupled to a fixed-frequency rectangular wave…
Battery charger with temperature control
Granted: October 11, 2011
Patent Number:
8035352
A battery charger integrated circuit with temperature control is disclosed that includes a temperature sensor circuit and a charging current generator circuit. Upon receiving a temperature reading voltage (VDT), the temperature sensing circuit is operable to generate a second reference voltage (VREF) that is a function of the first reference voltage (VREF1). The charging current generator circuit generates and continuously adjusts a reference current (I1) and a charging current (IOUT)…
Circuit system and method for reducing an in-rush current
Granted: September 27, 2011
Patent Number:
8026707
A circuit is provided including an output stage with a pair of transistors. Further provided is a control circuit in communication with the output stage. The control circuit is capable of controlling a duration in which at least one of the transistors is actuated for reducing an in-rush current.
Close-loop Class-D audio amplifier and control method thereof
Granted: August 23, 2011
Patent Number:
8004360
The present invention discloses a Class-D power amplifier and control method thereof. In one embodiment, the amplifier feeds back the signal at the output node to the inverting input of the comparator, and provides a high frequency triangular wave signal to the non-inverting input of the comparator. In addition, the non-inverting input of the comparator may be coupled to an offset voltage, while the inverting input of the comparator may be coupled to a fixed-frequency rectangular wave…
Method and flip chip structure for power devices
Granted: August 16, 2011
Patent Number:
7999364
A lead frame structure for supporting a semiconductor die is disclosed that includes at least two electrical leads each having a plurality of finger shaped structures unilaterally extending outward from the at least two electrical leads. The electrical leads are arranged so that the plurality of finger shaped structures forms inter-digital patterns where the semiconductor dies are bonded to the lead frame structure.
