====== Voltage Equations ====== ---- ===== 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)