PROTECTION FOR MODIFIED LED TUBE Russian patent published in 2018 - IPC H05B33/08 

FIELD: lighting.

SUBSTANCE: invention relates to light sources. Result is achieved that light sources (1), such as modified LED tubes, comprise lighting circuits (11) with LEDs (12) and feeding electrodes (13, 14), terminals (21-24) for exchanging signals with ballasts (2) or power supplies (4) and filament circuits (31, 41) for coupling terminals (21-24) and feeding electrodes (13, 14). Filament circuits (31, 41) comprise switch circuits and trigger circuits (32) for in response to presences of frequencies in the signals bringing switch circuits (32) into conducting states to introduce relatively low impedances in filament circuits (31, 41). In non-conducting states the switch circuits introduce relatively large impedances. This way, in case light source (1) is connected to high-frequency ballast (2), the switch circuit is triggered and light source (1) is normally activated. In case light source (1) is connected to mains (4) or an external direct-current driver or an electro-magnetic ballast, the switch circuit is not triggered, and light source (1) is not activated and protected against damage.

EFFECT: technical result is improved reliability of protection of the light source.

15 cl, 17 dwg