Thread: Are we still using only 256 unique PWM steps?
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Unread 08-06-2012, 10:16 PM
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Ether Ether is offline
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Re: Are we still using only 256 unique PWM steps?

Doing the math for grins, a 4 microsecond change in pulse width signal to the Victor corresponds to roughly 0.8% change in the duty cycle output which is approximately equivalent to a 0.1 volt change seen by the motor.

A 0.1 change in voltage to a CIM operating at 12 volts into a constant load at the max efficiency point on the curve results in about a 1% change in motor speed.

I wonder how stable and accurate the pulse width coming from the DSC is. Has anybody ever hooked it up to a logic analyzer?



Last edited by Ether : 08-07-2012 at 04:38 PM. Reason: I found some equipment with 1 MHz edge sampling. I'll re-post as time permits.
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