WM3100
Preliminary Technical Data
TERMINOLOGY
1. Signal-to-Noise Ratio (dB) – SNR is a measure of the difference in level between the maximum full scale output
signal and the output with no input signal applied. (Note that this is measured without any mute function enabled.)
2. Total Harmonic Distortion (dB) – THD is the level of the rms value of the sum of harmonic distortion products relative
to the amplitude of the measured output signal.
3. Total Harmonic Distortion plus Noise (dB) – THD+N is the level of the rms value of the sum of harmonic distortion
products plus noise in the specified bandwidth relative to the amplitude of the measured output signal.
4. Dynamic range (dB) - DNR is a measure of the difference between the maximum full scale output signal level and the
sum of all harmonic distortion products plus noise with a low level input signal applied. Typically, an input signal level
60dB below full scale is used.
5. Channel separation (L/R) (dB) – left-to-right and right-to-left channel separation is the measured signal level in the
idle channel at the test signal frequency relative to the signal level at the output of the active channel. The active
channel is configured and supplied with an appropriate input signal to drive a full scale output, with signal measured
at the output of the associated idle channel.
6. Mute Attenuation – This is a measure of the difference in level between the full scale output signal and the output with
mute applied.
7. All performance measurements carried out with 20kHz low pass filter and, where noted, an A-weighted filter. Failure to
use such a filter will result in higher THD and lower SNR readings than are found in the Electrical Characteristics. The
low pass filter removes out of band noise; although it is not audible it may affect dynamic specification values.
PTD, October 2010, Rev 2.0
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WOLFSON [ WOLFSON MICROELECTRONICS PLC ]
