WM8994ECSSLASHR datasheet(30/363 Pages) CIRRUS

30 / 363 page

WM8994

Rev 4.6

TERMINOLOGY

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.

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.

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.

Power Supply Rejection Ratio (dB) - PSRR is the ratio of a specified power supply variation relative to the output signal that

results from it. PSRR is measured under quiescent signal path conditions.

Common Mode Rejection Ratio (dB)

– CMRR is the ratio of a specified input signal (applied to both sides of a differential

input), relative to the output signal that results from it.

Channel Separation (L/R) (dB)

– left-to-right and right-to-left channel separation is the difference in level between the active

channel (driven to maximum full scale output) and the measured signal level in the idle channel at the test signal frequency.

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.

Multi-Path Crosstalk (dB)

– is the difference in level between the output of the active path and the measured signal level in the

idle path at the test signal frequency. The active path is configured and supplied with an appropriate input signal to drive a full

scale output, with signal measured at the output of the specified idle path.

Mute Attenuation

– This is a measure of the difference in level between the full scale output signal and the output with mute

applied.

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.

WM8994ECS/R Datenblatt(PDF) 30 Page - Cirrus Logic