Patent ID: 8487554
Filing Date: 2013-07-16
Classification: H05B

Abstract:
1. A light generating device ( 20 ), comprising: an input ( a controllable current source ( a switch matrix ( a plurality of n LED groups (D a controller ( wherein the controller is configured to control the switch state of the switches (S wherein the controller is capable of operating in at least three different control states, wherein in a first one of said control states the switches (S wherein the device further comprises a memory ( wherein the controller is configured to compare the momentary value of the DC input voltage (Vin) with said threshold levels; wherein the controller ( and wherein n wherein the switch matrix ( wherein the anode terminal (A wherein the cathode terminal (Kn) of the n-th LED (Dn) is connected to the second input terminal ( wherein a controllable switch (S(3m−5)) is arranged between the anode terminal (Am) of the m-th LED (Dm) and the anode terminal (A(m−1)) of the (m−1)-th LED (D(m−1)); wherein a controllable switch (S(3m−4)) is arranged between the anode terminal (Am) of the m-th LED (Dm) and the cathode terminal (K(m−1)) of the (m−1)-th LED (D(m−1)); and wherein a controllable switch (S(3m−3)) is arranged between the cathode terminal (Km) of the m-th LED (Dm) and the cathode terminal (K(m−1)) of the (m−1)-th LED (D(m−1)); for all values of m between 2 and n.