PCM1794: Simple circuit for a smartphone

Gennadiy Poznyakov

Part Number: PCM1794
Other Parts Discussed in Thread: , PCM2903C

Hello!

I need the most simple scheme for very high-quality conversion of sound files from a smartphone via USB-C. On the Internet, I found that very often they use the PCM1794 chip for this. Perhaps it is outdated and now you need to use a different chip?

The output signal will be sent to the mixer where it will be mixed with other audio signal. Then the signal to the low frequency amplifier. No other inputs than USB-C. No other adjustments. Simply very high quality music reproduction for live performances of vocalists.

over 2 years ago

0 Arash Loloee over 2 years ago

TI__Mastermind 23260 points

Hello, Conceptually it is correct. Both PCM1794 and OP2132 are great devices. You can also check with users guide for PCM1794 for other choices in terms of opamp and filter components.

SLEU057A–September 2004–Revised May 2009 page 17

Regards,

Arash

0 Gennadiy Poznyakov over 2 years ago in reply to Arash Loloee

Prodigy 140 points

Thank you! I would like to see an example of a real circuit on PCM1794. The one that will be suitable for use in my case.

Arash Loloee said:
SLEU057A–September 2004–Revised May 2009 page 17

Sorry, I didn't understand what that means.

I have seen this diagram. But my knowledge is not enough to understand what could be instead of squares on the left side.

As far as I understand, it is not possible to directly connect USB-C to the PCM1794a. What should be used in this case?

0 Arash Loloee over 2 years ago in reply to Gennadiy Poznyakov

TI__Mastermind 23260 points

Hello Gennadiy,

The boxes on the left side are exactly what the name says: basically you control the format of data, and other options on the chip.

Similar to any IC, you need to look at the pin out and then read the specific section of datasheet for that pin or function that is of your interest.

So from controller ox you can control various inputs that sets the format, channel selection and etc. You can manually set these pins yourself and no need to have a "controller". Table 2 describes the set up on these pins and the resulted function.

The picture above is a real example and typical circuit that uses PCM1794.

Regards,

Arash

0 Gennadiy Poznyakov over 2 years ago in reply to Arash Loloee

Prodigy 140 points

Unfortunately, the picture is not displayed. I'm very bad at digital.

Perhaps someone will tell you if it is possible to send a digital signal directly from a smartphone to JK? If so, what needs to be connected where?

+1 Arash Loloee over 2 years ago in reply to Gennadiy Poznyakov

TI__Mastermind 23260 points

I was referring to Fig 31 that you posted above in your reply , that is a real example and actual application circuit for PCM1794

In a nut shell you need to select the format using table 2 above and send the data/clks from your source of audio ( through an interface ). Here is a conceptual circuit for that.