Self-adjusted LED illumination system

摘要

Various embodiments of the present invention relate to a LED illumination system, and more particularly, to systems, devices and methods of employing a LED driver control loop to adjust the brightness of the LED light smoothly and suppress flickering/blinking. The LED driver control loop comprises a LED driver, a charge integrator, a VPWR modulator, and a driver controller. The charge integrator generates a voltage VC that is associated with a LED current iLED and illumination energy for the LED light. The VPWR modulator provides a clamping voltage VPWR such that the LED driver ceases to inject the LED current iLED as the voltage VC saturates at VPWR during each powering cycle. The clamping voltage VPWR is dynamically adjusted at the end of each powering cycle to gradually adjust the brightness and avoid flickering or blinking while still ensuring illumination efficiency.

主权项

1. A light-emitting diode (LED) driver control loop that drives a LED light, comprising:
a LED driver, coupled to the LED light, the LED driver receiving a switched mode supply and generating a LED current to drive the LED light according to a driver control, the switched mode supply being a pulsed voltage that comprises a plurality of powering cycles and including a dead band between every two consecutive powering cycles; a charge integrator, coupled to the LED driver and the LED light, the charge integrator generating a charging voltage that increases at a rate associated with the LED current during each powering cycle; a driver controller, coupled to the charge integrator, the driver controller disabling the driver control when the charging voltage reaches a clamping voltage during each powering cycle and resetting the driver control at the end of each powering cycle; and a voltage modulator, coupled to the driver controller, the voltage modulator adjusting the level of the clamping voltage according to the driver control at the end of each powering cycle.