Abstract: The present invention provides an apparatus and method for reducing jitter in a periodic signal. The apparatus comprises: a frequency discriminator configured to receive the periodic signal and feedback of an output signal of the apparatus and calculate an estimate value for a length of a current period of the periodic signal; a phase discriminator configured to receive the periodic signal and determine an adjustment factor for the length of the current period of an input signal according to the input signal in a previous period of the periodic signal and the output signal in the previous period of the apparatus; and an adjustor configured to determine the period length of the output signal in the current period according to the estimate value for the length of the current period and the adjustment factor for the length of the current period.

Abstract: Various embodiments of the present invention relate to a reference voltage generator circuit. Specifically, the circuit may for example comprise: a mirror constant current source having a first branch and a second branch, wherein a first current on the first branch is proportional to a second current on the second branch; wherein the first branch has a first resistive element, and the second branch has two second resistive elements connected in series; and a power supply terminal located between said two second resistive elements on the second branch. A high-precision reference voltage relative to the voltage source can be provided at the power supply terminal by using the circuit provided by various embodiments of the present invention.

Abstract: A power converter with fast discharging to adapt to a load disconnect. The power converter comprises a magnetic component coupled between an input of the power converter and an output of the power converter. The magnetic component includes a primary winding and a secondary winding. A switch controls transfer of energy from the primary winding to the secondary winding according to on and off times of the switch. A discharge circuit is coupled to the output of the power converter. The discharge circuit is adapted to receive a signal indicative of whether the load is disconnected and to decrease an output voltage at the output of the power converter based on the signal indicative of whether the load is disconnected.

Abstract: The embodiments herein describe a switched mode power converter. In particular, the embodiments herein disclose techniques for adaptive synchronous rectification control. The switched mode power supply includes a synchronous rectifier controller that determines when to turn off the synchronous rectifier during each switching cycle based on a reference signal corresponding to when substantially all the power stored in a transformer of the power supply has been delivered to an electronic load. The synchronous rectifier controller may determine whether to adjust the reference signal used by the synchronous rectifier controller to turn off the synchronous rectifier during subsequent switching cycles.

Abstract: The present invention relates to a square wave generator circuit, an integrated circuit, a DC/DC converter and an AC/DC converter.

Abstract: The present invention provides a level translator circuit, a driving circuit for driving a high-voltage device and a corresponding method. The driving circuit for driving a high-voltage device comprises: a zener diode whose cathode is connected to a high-voltage power supply voltage and whose anode is connected to a ground potential of a low-voltage domain through a resistor; a high-voltage PMOS transistor whose gate is connected to an anode of the resistor, whose drain is connected to the ground potential of the low-voltage domain, and whose source is operable to supply a ground potential of a high-voltage domain; a level translator operable to convert a first signal in the low-voltage domain as received to a second signal in the high-voltage domain and output the second signal; and a low-voltage driving circuit operable to receive the second signal and adapt the second signal as a third signal which can drive the high-voltage device.

Abstract: The embodiments herein describe a switched mode power converter. In particular, the embodiments herein disclose a method for powering a synchronous rectifier controller that enables synchronous rectification in the switched mode power converter. The synchronous rectifier controller may be enabled by a regulator circuit or directly from the output voltage.

Abstract: A primary-only power supply enables transmission of a signal or message from the secondary side of an isolated power supply to the primary side. To enable robust detection of the message without interfering with primary side sensing for output regulation, a configurable impedance current path is configured between the primary winding and ground. The primary side controller controls the configurable impedance current path to have a relatively low impedance during the normal mode and a relatively high impedance during the messaging mode.

Abstract: This specification relates to a method and a system for detecting light emitting diode (LED) short circuit in a plurality of LED strings or detecting matching among the plurality of LED strings, wherein one end of each of the plurality of LED strings is connected to a same output end of a power supply, and the other end is respectively connected to a corresponding switch. According to the present invention, first current of each of LED strings is obtained when the output end of the power supply outputs a first voltage; differences between the minimum of the first currents of LED strings and other first currents are calculated; the differences are compared with a comparing threshold; it is determined that the LED strings corresponding to the other currents for which differences are larger than the comparing threshold include short circuit or mismatch with the LED string corresponding to the minimum current. Accordingly, it is possible to reduce the number of pins and area of a control chip.

Abstract: A LED lighting system, such as a dimmable LED lamp, that may simulate the performance of an incandescent bulb. LED strings of different colors may be connected to the output of a single LED driver that regulates an overall intensity of light produced by the LED lighting system. The color of the LED lighting system may be controlled by circuitry, such as one or more switches, that allocates current between the LED strings to change the color temperature of light emitted by the LED lighting system as the light intensity changes.

Abstract: Embodiments disclosed herein describe the use of two inductors in a non-isolated power converter. The power converter receives power from a non-regulated power source, and converts the received power to regulated output signals. Each inductor in the power converter receives power provided from the non-regulated power source via a switch controlled by a controller, and provides a regulated output to a power converter load. A first regulated output provided by a first inductor can be representative of a second regulated output provided by a second inductor. In addition, a voltage feedback signal can be provided for use by the controller based on the first regulated output and/or the second regulated output.

Abstract: A switching power converter provides a communication link between a secondary side and a primary side of the switching power converter. During a messaging mode, the communication link enables information to be transmitted from an electronic device coupled to the secondary side to a controller on the primary side. The communication link may be used to transmit operating parameters related to powering the electronic device. The switching power converter may then adapt its switching operation to achieve different regulated output voltage and/or current to accommodate the detected electronic device.

Abstract: A TRIAC dimmer controller for an LED lamp dynamically adjusts the amount of additional current supplied to the TRIAC dimmer based on the TRIAC dimmer operating mode. A TRIAC dimmer current controller continually senses the TRIAC dimmer current loading and determines a TRIAC dimmer operating mode based on the detected current. The TRIAC dimmer controller compares the detected current with a threshold current value called a TRIAC holding current, and adjusts the amount of bleeder current based on the difference between the detected current and the threshold current value. By continually sensing the TRIAC dimmer current loading, the LED controller regulates the amount of bleeder current supplied to the TRIAC dimmer using a single sink current path to satisfy the TRIAC dimmer current demands of multiple TRIAC dimmer operating modes.

Abstract: The present invention provides an apparatus and method for reducing jitter in a periodic signal. The apparatus comprises: a frequency discriminator configured to receive the periodic signal and feedback of an output signal of the apparatus and calculate an estimate value for a length of a current period of the periodic signal; a phase discriminator configured to receive the periodic signal and determine an adjustment factor for the length of the current period of an input signal according to the input signal in a previous period of the periodic signal and the output signal in the previous period of the apparatus; and an adjustor configured to determine the period length of the output signal in the current period according to the estimate value for the length of the current period and the adjustment factor for the length of the current period.

Abstract: The embodiments disclosed herein describe a method of a controller to maintain a substantially constant average output current at the output of a switching power converter. In one embodiment, the controller uses a regulation voltage that corresponds to the primary peak current regulation level to regulate the average output current.

Abstract: The present invention provides a level translator circuit, a driving circuit for driving a high-voltage device and a corresponding method. The driving circuit for driving a high-voltage device comprises: a zener diode whose cathode is connected to a high-voltage power supply voltage and whose anode is connected to a ground potential of a low-voltage domain through a resistor; a high-voltage PMOS transistor whose gate is connected to an anode of the resistor, whose drain is connected to the ground potential of the low-voltage domain, and whose source is operable to supply a ground potential of a high-voltage domain; a level translator operable to convert a first signal in the low-voltage domain as received to a second signal in the high-voltage domain and output the second signal; and a low-voltage driving circuit operable to receive the second signal and adapt the second signal as a third signal which can drive the high-voltage device.

Abstract: Various embodiments of the present invention relate to a reference voltage generator circuit. Specifically, the circuit may for example comprise: a mirror constant current source having a first branch and a second branch, wherein a first current on the first branch is proportional to a second current on the second branch; wherein the first branch has a first resistive element, and the second branch has two second resistive elements connected in series; and a power supply terminal located between said two second resistive elements on the second branch. A high-precision reference voltage relative to the voltage source can be provided at the power supply terminal by using the circuit provided by various embodiments of the present invention.

Abstract: The present invention provides a reference voltage generator and a corresponding integrated circuit.

Abstract: The present invention relates to a square wave generator circuit, an integrated circuit, a DC/DC converter and an AC/DC converter.

Abstract: An LED lamp is provided in which the output light intensity of the LEDs in the LED lamp is adjusted based on the input voltage to the LED lamp. A dimmer control unit detects a type of dimmer switch during a configuration process. Using the detected dimmer type, the dimmer control unit generates control signals appropriate for the detected dimmer type to provide regulated current to the LEDs and to achieve the desired dimming effect. The LED lamp can be a direct replacement of conventional incandescent lamps in typical wiring configurations found in residential and commercial building lighting applications that use conventional dimmer switches.