Abstract:
A driving circuit for driving a light source includes a power converter, a controller and a voltage-controlled current source. The power converter is coupled to the light source, and receives an input voltage from a power source and provides an output voltage to the light source. The power converter includes a switch coupled in series with the light source. The controller is coupled to the power converter and controls a power of the light source by controlling the switch. The voltage-controlled current source is coupled to the controller and provides a first current. The controller controls the switch based on the first current.
Abstract:
A circuit for driving a light source includes a voltage converter, a switch and a controller. The voltage converter converts an AC input voltage signal to a first rectified AC voltage signal. The voltage converter further generates an average signal proportional to an average voltage level of the first rectified AC voltage signal. The switch is coupled to the light source in series. The controller coupled to the voltage converter and the switch compares the first rectified AC voltage signal with the average signal to generate a pulse signal. The controller further generates a dimming control signal based on the pulse signal to control the switch thereby controlling dimming of the light source.
Abstract:
A controller for controlling dimming of a light source includes a detection pin, an input signal pin, and a monitoring pin. The detection pin is operable for monitoring a rectified voltage and for detecting whether the rectified voltage comes from a TRIAC dimmer or an on/off switch dimmer. The input signal pin is operable for receiving an input signal indicative of the rectified voltage and the controller controls dimming of the light source according to the input signal if the rectified voltage comes from a TRIAC dimmer. The monitoring pin is operable for receiving a monitoring signal indicating an operation of the on/off switch dimmer and the controller controls dimming of the light source according to the monitoring signal if the rectified voltage comes from an on/off switch dimmer.
Abstract:
A circuit for driving a load includes a power line, converter circuitry, and a controller. The power line is operable for providing an input current and an input voltage. The converter circuitry coupled to the power line is operable for converting the input voltage to a regulated voltage to drive the load, and for providing a current detection signal indicating whether a converter current flowing through the converter circuitry drops to a predetermined level. The controller coupled to the converter circuitry is operable for correcting a power factor of the circuit based on the current detection signal and the input voltage such that a waveform of the input current follows a waveform of the input voltage.
Abstract:
There is provided a driving circuit for controlling power of a light source. The driving circuit includes a power converter and a dimming controller. The power converter is coupled between a power source and the light source, and can receive power from the power source and provide a regulated power to the light source. The dimming controller is coupled to the power converter, and can receive a switch monitoring signal. The switch monitoring signal can indicate an operation of a power switch coupled between the power source and the driving circuit. The dimming controller is further operable for adjusting the regulated power from the power converter by controlling a switch coupled in series with the light source according to the switch monitoring signal.
Abstract:
A restoring structure of a lock comprises: a sleeve disk, having a first wall and a second wall, the first wall interconnecting a first face and a second face, and the second wall interconnecting the second face and a third face, the first face and the second face defining a recess, the first face further having a projection, and the second wall defining a central hole; an integrally formed rotative tube, inserted through the central hole of the sleeve disk, and having an end which is formed with a bent portion at a location corresponding to the projection of the sleeve disk and has at least one protrusion disposed at a predetermined position, the protrusion abutting against the first face of the sleeve disk; a torsion spring having two legs, adapted to fit onto an outer wall of the rotative tube such that the legs engage on the bent portion of the rotative tube and the projection of the sleeve disk; and a guard ring disposed adjacent to the third face of the sleeve disk and adapted to engage with at least one lateral slot formed on the rotative tube; whereby when the rotative tube is rotated clockwise or counterclockwise at a desired angle, the torsion spring is compressed to create an elastic deformation such that the at least one protrusion of the rotative tube runs toward the projection of the sleeve disk, and when the rotative tube is released, the rotative tube is returned to its original position by a restoration force of the torsion spring.
Abstract:
A lock set for a door has a cylindrical spindle integrally coupled with a knob and containing a slide plate which can be actuated to lock and unlock the cylindrical spindle against rotation. The cylindrical wall of the spindle is provided with two diametrically opposing grooves which extend axially from one end thereof to a predetermined depth and which are opened at the one end so as to facilitate installation of the slide plate in the spindle. The slide plate has two opposing lugs for insertion into the grooves.
Abstract:
A controller for controlling power to a light source includes a first sensing pin, a second sensing pin, a third sensing pin, and a driving pin. The first sensing pin receives a first signal indicating an instant current flowing through an energy storage element. The second sensing pin receives a second signal indicating an average current flowing through the energy storage element. The third sensing pin receives a third signal indicating whether the instant current decreases to a predetermined current level. The driving pin provides a driving signal to a switch to control an average current flowing through the light source to a target current level. The driving signal is generated based on one or more signals selected from the first signal, the second signal and the third signal.
Abstract:
Embodiments of the invention provided a driving circuit for powering a light-emitting diode (LED) light source. The driving circuit includes a rectifier, a filter capacitor, and a control circuit. The rectifier converts an AC voltage from an AC power source to a rectified AC voltage. The filter capacitor coupled to the rectifier filters the rectified AC voltage to provide a DC voltage. The control circuit controls power supplied to the LED light source. The control circuit enables a discharging current periodically to discharge the filter capacitor if a switch coupled between an AC power source and a rectifier is turned off and disables the discharging current if the control circuit determines that the switch is turned on.