PCM1681: Connection between PCM1681 and PLL170X

Marco Antonio Zatarain

Part Number: PCM1681

Hi
I am a beginner in designing audio systems using DACs. My client wants a prototype that uses the PCM1681. He did not give me any more information, but I know that it will be implemented on a card for various tests.

Reading the datasheet, I realized that I needed an external master clock. My question is can I use the pcm1681 without the PLL?

In case I need the PLL, how can I connect it with the PCM1681?
Can the PLL generate the synchronized signal for BCK and LRCK or does the microcontroller have to generate them?

I add diagram of the connection that I made for the pcm1681.

over 2 years ago

0 Arash Loloee over 2 years ago

TI__Mastermind 19340 points

Hello Marco,

The master clock can come from either a dedicated IC such as the PLL170X series, a crystal or the audio source IC. What is important is that the audio source and the PCM1681 are driven from the same source so that the audio clocks will be synchronous.

Both LRCK and BCK must be synchronous with the system clock, SCK. Ideally, it is recommended that LRCK and BCK are derived from SCK.

I think that should cover your question.

Regards,

Arash

0 Marco Antonio Zatarain over 2 years ago in reply to Arash Loloee

Prodigy 10 points

Thanks a lot.

Now I understand it better, can I generate the SCK, BCK and the LRCK using an I2S connection?

The microcontroller I am using has an I2S interface.

Best regards!!

0 Arash Loloee over 2 years ago in reply to Marco Antonio Zatarain

TI__Mastermind 19340 points

If you can generate LRCK and BCK and SCK ( LRCK and BCK synced with system clock) then you can use I2S to send your data and clks.

Regards,

Arash

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PCM1681: Connection between PCM1681 and PLL170X