LED lighting systems and methods for constant current control in various operation modes

A system for providing at least an output current to one or more light emitting diodes, the system comprising:

• a control component configured to receive at least a demagnetization signal, a sensed signal and a reference signal and to generate a control signal based on at least information associated with the demagnetization signal, the sensed signal and the reference signal;
• and
• a logic and driving component configured to receive at least the control signal and output a drive signal to a switch based on at least information associated with the control signal;
• wherein:
• the switch is connected to a first diode terminal of a diode and a first inductor terminal of an inductor, the diode further including a second diode terminal, the inductor further including a second inductor terminal;
• the second diode terminal and the second inductor terminal are configured to provide at least the output current to the one or more light emitting diodes;
• the control signal is configured to regulate the output current at a constant magnitude;
• and
• the control component is further configured to receive at least the drive signal and to generate the control signal based on at least information associated with the demagnetization signal, the sensed signal, the reference signal, and the drive signal.

A method for providing at least an output current to one or more light emitting diodes, the method comprising:

• receiving at least a demagnetization signal, a sensed signal and a reference signal;
• processing information associated with the demagnetization signal, the sensed signal and the reference signal;
• generating a control signal based on at least information associated with the demagnetization signal, the sensed signal and the reference signal;
• receiving at least the control signal;
• processing information associated with the control signal;
• outputting a drive signal to a switch connected to a first diode terminal of a diode and a first inductor terminal of an inductor, the diode further including a second diode terminal, the inductor further including a second inductor terminal, the second diode terminal and the second inductor terminal being configured to provide at least the output current to the one or more light emitting diodes;
• regulating the output current at a predetermined magnitude based on at least information associated with the control signal;
• receiving a feedback signal, directly or indirectly, from the first diode terminal and the first inductor terminal;
• and
• generating the demagnetization signal based on at least information associated with the feedback signal.