User Guide/Appendix/Amplitude Measurements, Root Mean Square Value, VRMS: Difference between revisions
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Table 6: Peak<nowiki>-</nowiki>to-peak, RMS and AVG value conversion for sinusoidal waveforms:{ | Table 6: Peak<nowiki>-</nowiki>to-peak, RMS and AVG value conversion for sinusoidal waveforms: | ||
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Latest revision as of 10:14, 10 November 2015
The RMS value of an alternating current is that current which will give the same heating effect as the equivalent direct current. The RMS value of y=f(x) over the range x=a to x=b is given by:
RMS value = 
The mean or average value of a waveform between x=a to x=b is given by:
AVG value = 
For simple tones (sinusoidal waveforms) the relationships between RMS value, AVG value, peak and peak-to-peak value are given in Table 6.
| from value | multiplication factor to value | |||
| average | RMS | peak | peak-to-peak | |
| average | 1.0 | 1.11 | 1.57 | 3.14 |
| RMS | 0.9 | 1.0 | 1.414 | 2.828 |
| peak | 0.637 | 0.707 | 1.0 | 2.0 |
| peak-to-peak | 0.32 | 0.3535 | 0.5 | 1.0 |
Table 6: Peak-to-peak, RMS and AVG value conversion for sinusoidal waveforms:
| Coding bits/sample: n | 8 | 16 | 18 | 20 | 22 | 24 | 32 |
| FS ratio: N/1 | 28 | 216 | 218 | 220 | 222 | 224 | 232 |
| FS ratio: dB | 48 | 96 | 108 | 120 | 132 | 144 | 192 |
| Note: dB (FS) = 20 * lg(N) = 20 * lg(2n) = 20*0.3010*n |
Table 7. Full Scale Range (dB FS) available at different digital word lengths (bits/sample).
