How To Solve The Led Flashing Phenomenon

Writer：Jane Time：2021-06-30 Browse：159

Q: A customer requires dimming, and they have a PWM signal for dimming in their system. The frequency is 90+/-10Hz, and the duty cycle is (1%-80%) +/-5%. When we use this signal, we find the LED flickers.

     A: May be not to do surface flow, the current is constantly fluctuating, affecting the brightness, the feeling is flickering. Add appropriate feedback resistors to the upper and lower bias and shooting stages of the triode to form a relative constant current source. In addition, some constant current drive IC can meet PWN and analog voltage dimming, if the PWM way has flashing, you can integrate the PWM signal, and then use the analog way to dimming, should be able to meet the requirements.