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Altera FPGA DE0 PWM LEDS

Altera_Forum
Honored Contributor II
‎07-20-2015 08:00 AM
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Hello everyone, 

I want to make PWM LEDS, i mean that pwm signal will control the intensity/brightness of the leds, such as this video: https://www.youtube.com/watch?v=83benzyirnq 

 

But how it could be possible when we have only '1' state which is 100% of brightness and '0' state which is 0% of brightness..? 

With pwm I can only change the frequency of the led but not the brightness, am i right? 

 

By the way I use FPGA Altera DE0 and i want to implement it in VHDL.
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Altera_Forum
Honored Contributor II
‎07-20-2015 03:06 PM
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Well PWM is the way to control the brightness. Basically you are flickering the LED on and off very fast; depending on the duty cycle the LED will appear to be brighter (long duty cycle) or dimmer (short duty cycle). 0% duty cycle = off, 100% duty cycle = always on = maximal brightness. Just pick a fast frequency to fool the eyes to not see flicker, but not too fast to allow for the LED to fully turn on - so like 1kHz would be ok.

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