Control circuit, control method and LED driving circuit thereof

A control circuit for a light-emitting diode (LED) driving circuit having a rectifier and a power transistor for driving an LED load, the control circuit comprising:

• a) a control signal regulation circuit configured to control a driving voltage of said power transistor to vary with a rectifier output voltage to control the variation of a current flowing through said power transistor to be consistent with that of said rectifier output voltage to decrease a power loss of said power transistor;
• and
• b) said control signal regulation circuit being configured to control said driving voltage of said power transistor to vary with said rectifier output voltage to control the variation of said current flowing through said power transistor to be opposite to that of said rectifier output voltage to improve a power factor of said LED driving circuit.