PWM this term, because in our drive PWM often used inside.
PWM Dimming (PWM), is the best LED grayscale adjustment method. PWM say more easy to understand, is to control the LED on and off the time scale, the proportion of time on and off divided into several levels, LED will show a corresponding number of gray.
PWM frequency: just said PWM LED is on and off the proportion of time to achieve, but the switching frequency can not make too low, at least to be deceived eyes. learn from the experience of generally greater than 100Hz TV Some LED display will be the camera shot, conditional on the proposed design is more reasonable 300-500Hz. In the three-color design application is usually by adjusting the LED current to achieve the expectations of the white balance and maximum brightness, by controlling the PWM to gray level to achieve.
LED numbers of gray levels the field and 7-color, 8, 16, 32, 64, 128, 256, 512 and other ways. it can be different orders of magnitude, these numbers the main level is to facilitate the digital line data processing only. such as have to be divided into 100, it is also possible. the product of three primary colors of the gray level, is the product number theory can reproduce the colors, we usually say that the number of colors.
For example: Single color is 256 colors, red 256 (grade) × Green 256 (grade) × Blue 256 (level) = 16777216 (16KK colors).