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Answered

PWM output resolution

Rick 3 months ago in IQANdesign updated by Gustav Widén (System support) 2 months ago 1

What is the min/max resolution for PWM outputs? We have an output with its min and max set to 13 and 22%, which is, I think, quite narrow. Making the max 1% higher makes a big difference already - does it help to provide floating-point numbers (ie, max := 22,3 %) or will these numbers get rounded internally?

Same question for the actual output. Does 13..22% mean the output will only have 9 steps? Or could it deliver an output of, let's say 16,35 %?


For the info, we are using a MC43 "single pin" output, C1:47, on a 125 Hz frequency.

Answered

The output resolution on MC4x is 1 μs, and the input to the PWMOUT channel is a 32-bit real. 


However, the min and max modulation ratio are integer numbers. 

Also, when you monitor the channel value in IQANdesign, you only see an integer number. 

Also see similar question here: https://forum.iqan.se/communities/5/topics/688-resolution-of-pwm-output