LED lighting system with accurate current control

1. A light emitting diode (LED) lighting system comprising:

a switching power supply for converting a phase modulated signal generated from a dimmer into an output voltage, wherein the dimmer is a phase cut dimmer and operates at a repetitive phase cut rate;

an LED controller coupled to the switching power supply; and

light emitting diodes (LEDs) coupled to the LED controller; and

wherein the LED controller controls a current of the LEDs and includes components to: calculate, based on the current of the switching power supply, an average current amount delivered to the LEDs in a time period, wherein the time period is based on the repetitive phase cut rate; and utilize an actual charge based on the current to modify a future switching timing of the switching power supply.

2. The LED lighting system of claim 1 wherein the LED controller controls dimming of the LEDs.

3. The LED lighting system of claim 2 wherein the LED controller controls dimming of the LED system over a wide dimming frequency range.

4. The LED lighting system of claim 1 further comprising: components to utilize the actual charge based on the current to modify the future switching timing of the switching power supply.

5. The LED lighting system of claim 4 wherein the components to utilize the actual charge further comprises: components to compare the actual charge amount to a desired charge amount for an active time period and compensate for a difference between the actual charge amount and the desired charge amount during a future active time period.

6. The LED lighting system of claim 5 wherein the desired target charge is based on phase delays in a rectified input voltage.

7. The LED lighting system of claim 5 wherein the active time period and the future active time period are based on an averaging period that is based on the repetitive phase cut rate.

8. The LED lighting system of claim 7 wherein the LED controller controls dimming of the LEDs.

9. The LED lighting system of claim 8 wherein the LED controller comprises a dimming controller and a current controller wherein the dimming controller drives the current controller.

10. The LED lighting system of claim 9 wherein the dimming controller is driven by the repetitive phase cut rate and the current controller is driven by a switching frequency rate and wherein the repetitive phase cut rate is different than the switching frequency rate.

11. A method for controlling a current in light emitting diodes (LEDs) of an LED lighting system, comprising:

converting, by a switching power supply, a phase modulated signal generated from a dimmer into an output voltage, wherein the dimmer is a phase cut dimmer and operates at a repetitive phase cut rate;

controlling, by the LED controller coupled to the switching power supply and the light emitting diodes, a current of the LEDs;

calculating, by the LED controller, based on the current of the switching power supply, an average current amount delivered to the LEDs in a time period, wherein the time period is based on the repetitive phase cut rate; and

utilizing, by the LED controller, the actual charge based on the current to modify a future switching timing of the switching power supply.

12. The method of claim 11 wherein controlling, by the LED controller coupled to the switching power supply and the light emitting diodes, a current of the LEDs further comprises: controlling, by the LED controller, dimming of the LEDs.

13. The method of claim 12 wherein controlling, by the LED controller, dimming of the LEDs further comprises: controlling, by the LED controller, dimming of the LEDs over a wide dimming frequency range.

14. The method of claim 11 further comprising: utilizing, by components, the actual charge based on the current to modify the future switching timing of the switching power supply.

15. The method of claim 14 further comprises: comparing, by components, the actual charge amount to a desired charge amount for an active time period; and compensating, by the components, for a difference between the actual charge amount and the desired charge amount during a future active time period.

16. The method of claim 15 wherein the desired target charge is based on phase delays in a rectified input voltage.

17. The method of claim 15 wherein the active time period and the future active time period are based on an averaging period that is based on the repetitive phase cut rate.

18. The method of claim 11 wherein utilizing, by the LED controller, the actual charge to modify and provide a desired target charge amount to be delivered further comprises: utilizing the actual charge to modify and provide the desired target charge amount to be delivered during the future active time period of the LED current time period, wherein the future active time period is based on the repetitive phase cut rate further comprises; comparing the actual charge amount to a desired charge amount for the active time period; and compensating for a difference between the actual charge amount and the desired charge amount during the future active time period.

19. The method of claim 18 wherein controlling, by the LED controller coupled to the switching power supply and the light emitting diodes, a current, further comprises: controlling, by the LED controller, dimming of the LEDs.

20. The method of claim 19 wherein the LED controller comprises a dimming controller and a current controller and further comprising: driving, by the dimming controller, the current controller.

21. The method of claim 20 wherein driving, by the dimming controller, the current controller further comprises: driving the dimming controller at the repetitive phase cut rate; and driving the current controller at a switching frequency rate that is different than the repetitive phase cut rate.