Patent application number | Description | Published |
20130038234 | DIMMING REGULATOR INCLUDING PROGRAMMABLE HYSTERETIC DOWN-CONVERTER FOR INCREASING DIMMING RESOLUTION OF SOLID STATE LIGHTING LOADS - A system providing deep dimming of a solid state lighting (SSL) load includes a hysteretic down-converter, a shunt switch, a controller and a comparator. The down-converter controls average current value and amplitude of ripple of SSL current using amplitude modulation (AM) dimming control. The shunt switch controls magnitude of the SSL current using pulse width modulation (PWM) dimming control. The controller generates first and second PWM signals for controlling upper and lower current levels at which the down-converter operates based on the SSL current and voltage across the SSL load, and generates a third PWM signal for controlling the shunt switch based on a dimming level load set by a dimmer. The comparator circuit compares first and second analog signals corresponding to the first and second PWM signals with the SSL current, and drives the down-converter in response to the comparison. The SSL current is based on both the AM dimming control and the PWM dimming control. | 02-14-2013 |
20140103823 | LED LIGHT SOURCE - A LED light source comprises a full bridge rectifier equipped with a first input terminal and a second input terminal for coupling to output terminals of the phase cut dimmer, a series arrangement comprising N LED loads, a first and second end of said series arrangement being coupled to a first output terminal and a second output terminal of the full bridge rectifier respectively, control means for during a period of the rectified AC supply voltage subsequently making the LED loads comprised in the first series arrangement carry a current, one by one and in dependency of the momentary amplitude of the rectified AC supply voltage when the momentary amplitude increases and for subsequently making the LED loads stop carrying a current, one by one, and in dependency of the momentary amplitude of the rectified AC supply voltage when the momentary amplitude decreases, said control means controlling the current through the LED loads at zero when the output voltage of the phase cut dimmer equals zero and controlling the current through the LED loads at a value that is independent from the phase angle of the phase cut dimmer when the output voltage of the phase cut dimmer differs from zero Volt. In order to make the LED light source compatible with a phase cut dimmer, the LED light source is further equipped with a switchable bleeder current source coupled between the first and second output terminal of the full bridge rectifier, a latch coupled between the first and second output terminals of the full rectifier bridge and comprising a series arrangement of a resistor and a capacitor to prevent the current through the dimmer from crossing zero after a leading edge generated by the phase cut dimmer, in case the phase cut dimmer is a leading edge phase cut dimmer, a unidirectional element arranged in series with the capacitor for preventing discharging of the capacitor via the LED loads or the adjustable bleeder current source, and a clamp circuit coupled to the capacitor and comprising a current source for discharging the capacitor and providing a low ohmic path for the dimmer current when the dimmer is off. | 04-17-2014 |
20140103825 | LED LIGHT SOURCE - A string of LED loads is supplied by means of a rectified mains voltage. A cathode of each LED load is coupled to ground by means of a string. The strings are made conductive and non-conductive one by one in dependency of the instantaneous value of the rectified mains using both voltage and current sensing. | 04-17-2014 |
20140119046 | Arrangement for light balancing - There is provided an arrangement for light balancing. The arrangement provides light balancing and robust flux feedback and comprises a light source array, a plurality of light sources arranged as a plurality of strings of individual light emitting diodes, at least one light guide structure, and at least one optical sensor. The arrangement provides feedback relating to the optical contribution for each one of the plurality of strings of individual light emitting diodes and is thereby maintaining the emitted light at a balanced level. | 05-01-2014 |
20140197740 | LED LIGHT SOURCE - A LED light source comprises a first rectifier (DB | 07-17-2014 |
20140375223 | LED LIGHT SOURCE - LED light source suitable for use with a phase cut dimmer (III), comprising •input terminals (K1, K2) for connection to an AC supply voltage, •a rectifier (I) coupled to the input terminals, | 12-25-2014 |
20150061499 | LIGHT GENERATING DEVICE - A light generating device ( | 03-05-2015 |
20150319818 | CIRCUIT ARRANGEMENT AND LED LAMP COMPRISING THE SAME - A circuit arrangement for operating at least one low-power lighting unit with a phase-cut operating voltage from a power supply is disclosed, which circuit arrangement comprises a serial setup of an input device ( | 11-05-2015 |