User's Manual

9. Audio Trace
If possible, the audio trace should be placed in inner layer, and shielded by ground in the same layer
and the upper and lower adjacent layers to prevent from RF interference. In addition, it is
recommended to add as many via as possible between ground layers so as to reduce RF noise.
The AGND signal is usually used for AOUT2 channel to establish a single-end output with
SPK2P. Do not pair GND with SPK2P to establish an audio output, otherwise TDD (Time
Division Duplex) noise from power supply could occur in AOUT2.
Figure 5: Audio trace routing example