Duty cycle is the amount of time in a period that an LED is lighted. In that 5 column display each column is updated one at a time and so each LED in that matrix can be lighted for 20% or 1/5th of the time.
Refresh rate is how often you light each LED in the display over time. It's usually expressed in Hertz (cycles per second). In that 5 column display each column is lighted for 3.2 msecs and so it will take 16 msecs to update the entire 5 column display. The refresh rate is therefor 1 / 0.016 seconds = 62.5 Hertz.
Hi Mike I totally understood thanks for the well explanation.
In the above example I totally understood the refresh rate.But I like to know what is the duty cycle driving an LED?If I need a duty cycle of 50% what do I have to adjust in the software?
If I adjust the 3.2 msecs time it will change only refresh rate isn't it?How do I adjust the Duty cycle?