SLAA856A July   2018  – July 2021 TAS5825M

 

  1.   Trademarks
  2. 1General Overview
  3. 2Advanced Emission Suppression
    1. 2.1 Spread Spectrum Modulation
    2. 2.2 Dephase and Multi-Device Phase Synchronization
  4. 3Printed Circuit Board Design for EMC
    1. 3.1 Printed Circuit Board Layout
    2. 3.2 Ferrite Bead Filter
    3. 3.3 Power Supply and Speaker Wires
    4. 3.4 TAS5825M Device Configurations
  5. 4TAS5825M EMI Test Results
    1. 4.1 EN55022 Radiated Emission Results
    2. 4.2 EN55022 Conducted Emission Results
    3. 4.3 Conclusions
  6. 5Revision History

Dephase and Multi-Device Phase Synchronization

In addition to the spread spectrum technology, the TAS5825M device employs dephase circuits to further reduce electromagnetic emission without degrading audio performance.

The dephase circuit improves EMI and noise performance by interleaving the switching timing between the two audio channels. This improved EMI and noise performance reduces conducted emission on the PVDD line because the output ripple current of the two audio channels will be out of phase, and the ripple peak current from the PVDD line will thus be reduced to half value.

Also, TAS5825M supports 45° phase shifts between multiple channels to reduce EMI in multi-device systems. See more details in the TAS5825M datasheet.