I was talking to a guy currently in college who had a lab in which he had to calculate the duty cycle of a sine wave. The professor provided a formula which he didn't remember. What's this about? In a square wave it's proportional to the average voltage, so I thought maybe it's a matter of having a DC component.
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Average voltage in a square wave? I think that would be more appropriate to say average in a sine wave or pulse train.
Avg = 2/Pi; Vp = Peak Voltage; Pk = RMS*1.414;
in any case, Vavg = Vp in a 50% duty square wave (+&-) No difference there.
A pulse train, that is an ON and base line off, no (-)
Vavg = (b/a)*Vp; B = ON Time, A = the time from the start of ON time to the next start of on time.
In a sine wave the average is 2/pi * Vp = 0.636 * Vp
A triangle wave:
Vavg = Vp * .5;
A trapezoid wave
Vavg = A+B / 2* A *Vp
(A) being the base line width and (B) being the Peak width and Vp being the Peak voltage.
Jamie
Sounds meaningless to me. What was the answer?
John
50%
--Winston
"Duty cycle of a sine wave" works as well as "Blood pressure of a pine tree".
For some specific purpose there may be an _equivalent_ between the duty cycle of a square wave and of a sine wave. Or maybe the prof was thinking 50% (which is oddly obvious). Or something.
-- Tim Wescott Wescott Design Services http://www.wescottdesign.com Do you need to implement control loops in software? "Applied Control Theory for Embedded Systems" was written for you. See details at http://www.wescottdesign.com/actfes/actfes.html
"Duty cycle of a sine wave" works as well as "Blood pressure of a pine tree".
For some specific purpose there may be an _equivalent_ between the duty cycle of a square wave and of a sine wave. Or maybe the prof was thinking 50% (which is oddly obvious). Or something.
Tim Wescott I usually find it non-productive to guess what the assignment was meant to accomplish. A good deal of the time the assignment was not even perceived correctly by the student. They come here looking for answers but they don't know the question.
Tom
50%, if the DC offset is zero.
-- You can't fix stupid. You can't even put a band-aid on it, because it's Teflon coated.
"Tom Del Rosso"
** Normally, continuous sine and square waves are bipolar waves with average values of zero - so, unless gated on and off, their duty cycles are both 1 or 100%.With a rectangular pulse wave that only swings from zero to some value, the duty cycle is proportional to the average value - only becoming 1 when the average and peak values are identical.
If a (continuous) sine wave is offset from zero - it has an average value the same as that offset.
The " duty cycle of a sine wave" is, as my high school maths teacher would have wryly said - " undefined ".
.... Phil
I didn't ask what the answer or the "right" answer were.
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Possibly he got the term mixed up with phase or something. It's even possible the professor did.
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100%. 1-((time@zero)/time(non-zero))x100%
Well, with Maple it can matter. :-)
I am a Druid; I have been washed in the blood of The Tree. ;-)
(That's what you tell people when they comment on the roach clip pendant.)
Cheers! Rich
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