UroBoros
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I need to slowly DIM and slowly make a LED brighter. The LEDs are ceiling lights may be in the range of 6W-12W. it is having a SMPS already there.
So I plan to introduce a MOSFET between the SMPS and LED which in turn will PWM'ed from a Microcontroller. This is my plan and I tried it, but the dimming is not smooth especially in the extreme low brightness area.
is there any commercial modules which can be interfaced to a micro controller for dimming leds?
1. is there any specific LED dimming ICs which can be controlled from a micro controller via SPI or IIC?
2.if we are doing PWM to dim and led using Micro controller what should be the optimum pwm period to get a smooth effect?
even if i tried the lowest possible pwm duty cycle, the led cannot be made to off in a linear fashion. is it because of the nature of LED lights or problem with MOSFET switching?
Thanks
So I plan to introduce a MOSFET between the SMPS and LED which in turn will PWM'ed from a Microcontroller. This is my plan and I tried it, but the dimming is not smooth especially in the extreme low brightness area.
is there any commercial modules which can be interfaced to a micro controller for dimming leds?
1. is there any specific LED dimming ICs which can be controlled from a micro controller via SPI or IIC?
2.if we are doing PWM to dim and led using Micro controller what should be the optimum pwm period to get a smooth effect?
even if i tried the lowest possible pwm duty cycle, the led cannot be made to off in a linear fashion. is it because of the nature of LED lights or problem with MOSFET switching?
Thanks