TPA3111D1-Q1: TPA3111D1-Q1/TPA3110-Q1 RE

Hi Lei,

The data you show above is CE test, right?

The 300kHz freq interference is from the PWM freq. Are you using inductors in the output filter?

Best regards,

Shawn Zheng

Hi Lei,
The PWM signal is strong, it could radiate by the output traces. But usually it should be suppressed obviously by the inductors. Please make sure the LC filter is close to the AMP output pins as much as possible. Else, the long traces could work as antenna. Please also use as short speaker cables as possible. Please add 100uF+0.1uF+1nF decoupling caps on PVCC. For the SCH design, please refer to our EVM: www.ti.com/.../slou270a.pdf
Best regards,
Shawn Zheng

Hi Lei,
Right, it's fixed on TPA3111D2-Q1. Our latest product TPA3138D2 has spectrum spread feature, and it helps to improve EMI performance obviously. But unfortunately it doesn't have Q1 version.
Best regards,
Shawn Zheng

Hi Lei,
We are considering this, but this is schedule for it for now.
Best regards,
Shawn Zheng