TPA3118D2-Q1: Please review the schematic, and have some questions.

Dear Derek,

Thank you for your support.

I found that frequency specification which my customer said is about lowpass filter before the input source.

and here is another question.

I cannot find any lowpass filter related to the input. (especially RINP and LINP in the customer's schematic)

Is there any lowpass filter that does not presented on block diagram?

- If yes, Can we adjust the frequency response of lowpass filter?

- If no, Can we just add RC lowpass filter before RINP and LINP input?

Please check this issue. Thanks.

Best regards,

Chase

HI Chase

Chase Jeong said:

I cannot find any lowpass filter related to the input.

May I ask why do we need a lowpass filter? It's not very necessary. Not every customer need to add additional RC filter.

Dear Shadow,

Thank you for your support.

As I mentioned, my customer wants to process signal which frequency is 20~20KHz ± 3dB.

I this case Don't I need to use lowpass filter in front of the input pin?

Please check it again. Thanks.

Best regards,

Chase

Dear Shadow,

Thank you for your support. Here are 2 more questions from my customer.

1. I can find C11 and R11 (P30, BSPR) in the schematic of TPA3118D2 EVM. but I cannot fine same components in the reference schematic in the datasheet.

What is the exact purpose of C11 and R11?

2. I found the layout guidelines below in the datasheet l

The LC filter should be placed close to the outputs. The capacitors used in both the ferrite and LC filters should be grounded.

-> This output means the output of IC? or speaker output (speaker connector) ?

Please check this issue. Thanks.

Best regards,

Chase