We are know that, the led will be lit when current through the led, and there are two kind of way to adjust the luminous of led. one is change current , other one is PWM In here, we are think that to adjust driver current of LED, because they are mostly positive proportion .both the led bright and led work current. but there are a question in here when change led bright through adjust forward current, the way also change light spectrum and color temperature when adjust led bright at time. that is reason it has color slanting. in general the white led was made by blue led and yellow phosphor .along with the bright of blue led was increased and the thick of yellow phosphor is invariant, it will increase the main wavelength of light spectrum. they are not problem for the normal light device . but there will are a flicker in small work current. unless the range of const current is width, for example the range between 0 to highest . that is all right. sample work in here , the small work current will trigger flicker when with current way to adjust led bright.