Mathematically, RMS of a periodic function f(x) is, by definition:

sqrt(int(0,T, f^2(x), dx)/T )

In plain english, Root means square of a periodic function f(x) is the
square root of the integral average of the square of the function.  The
"means" part of RMS comes from the integral followed by the division of the
period T.

So, if you work out the math for a sine wave, you will get 1/sqrt(2) =
0.707.  For the other two you need to take into account the duty cycle of
the waveform and the DC offset of them.

If you have 50% duty cycle and the wave has no DC offset, then the math is
very easy.

For square wave, the RMS is the same as peak to peak.
For a triangular wave, symmetrical about the x-axis with 50% duty cycle, the
RMS is 1/sqrt(3), which is .577.  (I used Mathcad to do this one.  :)

There you have it.

Ben
-----Original Message-----
From: Donovan Parks [mailto:dparks@UVIC.CA]
Sent: Sunday, October 07, 2001 9:10 PM
To: PICLIST@MITVMA.MIT.EDU
Subject: [EE]: RMS Voltage to PP Voltage Conversions


Hello,

I need to convert some RMS voltage readings to PP (peak-to-peak) voltages.
The waveforms being used are a sinusodial, square, and triangle.  Does
anyone know the conversions for these waveforms?

Thanks,
Donovan Parks

--
http://www.piclist.com#nomail Going offline? Don't AutoReply us!
email listserv@mitvma.mit.edu with SET PICList DIGEST in the body

--
http://www.piclist.com hint: To leave the PICList
mailto:piclist-unsubscribe-request@mitvma.mit.edu