RGB LED architecture for color controllable LED filament

A LED filament device comprising:

• a LED filament having a plurality of sources of light, wherein:
• the sources of light are configured in an k*l array with k=2 columns, the array having a first set of at least 20 sources of light distributed over the columns, and the sources of light having solid state light sources;
• in a first column of the first set, at least 90% of a total number of sources of light are selected from a group consisting of first sources of light and fifth sources of light, with at least 40% of the total number of sources of light having first sources of light, and with 0-60% of the total number of sources of light having fifth sources of light;
• in a second column of the first set, at least 80% of the total number of sources of light are selected from a group consisting of second sources of light, third sources of light, and fourth sources of light, and in the second column of the first set at least 20% of the total number of sources of light has second sources of light, at least 20% of the total number of sources of light has third sources of light, and at least 20% of the total number of sources of light has fourth sources of light;
• the first sources of light are configured to generate first light having a first correlated color temperature (CCT1), the second sources of light are configured to generate second light having a second correlated color temperature (CCT2), the third sources of light are configured to generate blue third light, the fourth sources of light are configured to generate green fourth light, and the fifth sources of light configured to generate red fifth light;
• and
• CCT1 is selected from a range of at maximum 2400 K, CCT2 is selected from a range of at least 2700 K, and CCT2-CCT1≥500 K.