A power supply circuit (201, 301) adapted to supply power to a control circuit (202, 302) of a LED lighting, wherein the LED lighting comprises: - a plurality of LED light sources (D1, D2,..., Dn) connected in series, wherein the plurality of LED light sources (D1, D2,..., Dn) comprises a first group of LED light sources (D4.. Dn) and a second group of LED light sources (D1.. D3) - a power input of the plurality of LED light sources, wherein the first group of LED light sources (D4.. Dn) is coupled between the power input and the second group of LED light sources (D1.. D3), - the control circuit (202, 302), - a control switch adapted to be controlled by the control circuit (202, 302) so as to control on and off of a current path of the plurality of LED light sources (D1, D2,..., Dn), wherein the second group of LED light sources (D1.. D3) is coupled between the first group of LED light sources (D4.. Dn) and the control switch, the power supply circuit (201, 301) being characterized in that it comprises: - a first PNP transistor whose collector is coupled to a power input of the control circuit, whose emitter is coupled to a first node between the first group of LED light sources (D4.. Dn) and the second group of LED light sources (D1.. D3) and whose base is coupled to a second node between the control switch and the second group of LED light sources (D1.. D3), such that when the control switch controls the current path to close, the first PNP transistor is switched on and when the control switch controls the current path to open, the first PNP transistor is switched off; - a second NPN transistor whose base is coupled to the emitter of the first PNP transistor, and whose emitter is coupled to the power input of the control circuit, and whose collector is coupled to the power input of the plurality of LED light sources (D1, D2,..., Dn). - a plurality of LED light sources (D1, D2,..., Dn) connected in series, wherein the plurality of LED light sources (D1, D2,..., Dn) comprises a first group of LED light sources (D4.. Dn) and a second group of LED light sources (D1.. D3) - a power input of the plurality of LED light sources, wherein the first group of LED light sources (D4.. Dn) is coupled between the power input and the second group of LED light sources (D1.. D3), - the control circuit (202, 302), - a control switch adapted to be controlled by the control circuit (202, 302) so as to control on and off of a current path of the plurality of LED light sources (D1, D2,..., Dn), wherein the second group of LED light sources (D1.. D3) is coupled between the first group of LED light sources (D4.. Dn) and the control switch, the power supply circuit (201, 301) being characterized in that it comprises: - a first PNP transistor whose collector is coupled to a power input of the control circuit, whose emitter is coupled to a first node between the first group of LED light sources (D4.. Dn) and the second group of LED light sources (D1.. D3) and whose base is coupled to a second node between the control switch and the second group of LED light sources (D1.. D3), such that when the control switch controls the current path to close, the first PNP transistor is switched on and when the control switch controls the current path to open, the first PNP transistor is switched off; - a second NPN transistor whose base is coupled to the emitter of the first PNP transistor, and whose emitter is coupled to the power input of the control circuit, and whose collector is coupled to the power input of the plurality of LED light sources (D1, D2,..., Dn).