Method and apparatus for LED lighting

An apparatus, comprising:

• a first transistor, a first inductor, a first diode, and a capacitor coupled in a boost configuration to generate an intermediate power supply;
• a second transistor, a second inductor and a second diode coupled in a buck configuration to provide a first driving voltage based on the intermediate power supply to drive a first load device, the second transistor and the second diode being serially coupled between the intermediate power supply and a ground, the second inductor being coupled between the second diode and the first load device;
• a third transistor, a third inductor and a third diode coupled in the buck configuration to provide a second driving voltage based on the intermediate power supply to drive a second load device, the third transistor and the third diode being serially coupled between the intermediate power supply and the ground, the third inductor being coupled between the third diode and the second load device;
• and
• a controller configured to provide a first signal to the first transistor to switch on and off the first transistor to transfer electric energy from an input power supply to the capacitor to generate the intermediate power supply having a higher voltage than the input power supply, provide a second signal to the second transistor to switch on and off the second transistor to provide the first driving voltage based on the intermediate power supply to drive the first load device, and provide a third signal to the third transistor to switch on and off the third transistor to provide the second driving voltage based on the intermediate power supply to drive the second load device.

A method, comprising:

• providing first pulses to a first switch in a boost circuit to switch on and off the first switch in order to transfer electric energy from an input power supply to a capacitor to generate an intermediate power supply having a higher voltage than the input power supply;
• providing second pulses to a second switch in a buck circuit to provide a first driving voltage based on the intermediate power supply to drive a first load device and regulate a first current to the first load device, the buck circuit including a first diode and a first inductor, the second switch and the first diode being serially coupled between the intermediate power supply and a ground, the first inductor being coupled between the first diode and the first load device;
• and
• providing third pulses to a third switch in the buck circuit to provide a second driving voltage based on the intermediate power supply to drive a second load device and regulate a second current to the second load device, the buck circuit including a second diode and a second inductor, the third switch and the second diode being serially coupled between the intermediate power supply and the ground, the second inductor being coupled between the second diode and the second load device.