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====== Voltage Equations ======

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===== Vpp,Vrms =====
The following different terminologies and units are used for the calculations around alternating voltages:
  * **V//Peak// (V//p// or V//max//)**: The maximum instantaneous value of a function as measured from the zero-volt level. For the waveform shown above, the peak amplitude and peak value are the same, since the average value of the function is zero volts.
  * **V//Peak−Peak// (V//pp//)**:The full voltage between positive and negative peaks of the waveform; that is, the sum of the magnitude of the positive and negative peaks.
  * **V//rms//** : The root-mean-square or effective value of a waveform.
  * **V//avg// or V//DC//** : The level of a waveform defined by the condition that the area enclosed by the curve above this level is exactly equal to the area enclosed by the curve below this level.

{{ :other:electronics:wave-measurements.jpg?400 |}}

These values can be easily converted to each other. The way formulas for these conversions differ upon the the waveform that applies (sinus, triangle, square). The relevant basic conversions are: 

==== Sinus ====
  * ''** V//p// = V//pp// / 2 **''
  * ''** V//dc// = V//avg// = ( 2 * V//p// ) / π  **''
  * ''** V//rms// = V//p// / √(2) **''
  * ''** V//rms// = V//pp// / (2 * √(2)) **''
  * ''** V//pp// = 2*√(2) * V//rms// **''

==== Triangle ====
  * ''** V//dc// = V//avg// = V//p// / 2  **''
  * ''** V//rms// = V//p// / √(3) **''

==== Square ====
  * ''** V//p// = V//pp// / 2 **''
  * ''** V//dc// = V//avg// = V//p//  **''
  * ''** V//rms// = V//p// **''

===== Slew Rate vs Frequency =====
When SR is the SlewRate in V/s, F is the operating frequency, and Vpk is the peak amplitude of the waveform, i.e. half the peak-to-peak swing of a sinusoid. 

  SR >= 2*Pi*F*Vpk

  Fmax = SR / (2*Pi*Vpk)