LED dimming and driving method and circuit using the same

摘要

In an LED dimming and driving method and its circuit, a receiver, a current source and a controller are installed in a dimming module, and after the receiver has received a dimming signal, the current source is driven to output a current with a magnitude corresponsive to the dimming signal, and then after the controller has converted the current into a voltage level by a terminal resistor, the magnitude of the driving current of the LED is adjusted according to the voltage level to improve a linear dimming accuracy.

主权项

1. An LED dimming and driving method, comprising the steps of using a dimming module installed in an LED dimming and driving circuit to adjust the brightness of a plurality of LED strings; and using the dimming module to adjust a driving current of the LED strings by a current signal to achieve the effect of enhancing a linear dimming accuracy, characterized in that after the dimming module receives a dimming signal, an internal current source is driven to output current with a magnitude corresponsive to the dimming signal, and a terminal resistor is used to convert the current into a voltage level, and the driving currents are adjusted according to the voltage level to affect the brightness of the LED strings, wherein the dimming module intercepts the driving current by a current mirror to obtain a brightness value, and after the voltage level is compared with the brightness value, the current mirror adjusts the magnitude of the driving currents to achieve a linear dimming effect.