Light emitting device current regulator circuit and control method thereof

A light emitting device current regulator circuit, for regulating a light emitting device current flowing through a light emitting device circuit, wherein the light emitting device circuit has a first end and a second end, the first end being coupled to a power supply circuit, the light emitting device current regulator circuit comprising:

• an internal voltage generation circuit coupled to the second end, which generates an internal voltage according to a voltage at the second end (second end voltage) to supply electrical power to the light emitting device current regulator circuit, wherein the internal voltage generation circuit includes a charge storage device for storing charges from the second end voltage to generate the internal voltage;
• and
• a current control circuit, coupled to the second end, the current control circuit regulating the light emitting device current according to a control signal, wherein the control signal at least intermittently reduces the light emitting device current to zero or a low current in order to raise the second end voltage such that the charge storage device is intermittently charged to maintain the internal voltage not lower than a minimum level required for operation of the light emitting device current regulator circuit.