Hardware for SPDIF out of a STM32F7 soc?

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Hello,

I consider have a look to implementing USB audio => software DSP => SPDIF for a active multi amplification project using a STM32F7 development board

I did not succeeded for find in ST documentation the hardware to add from the SPDIF pis of the controller to the RCA SPDIF out plug.

Would you know where I could find those information and schematics ? For information, I only need to have 20 cm between the board and the amps.

Note: I have already a STM32F4 board with I2S outputs, but I did not identified cheaper/easier options for SPDIF output, than buying another development board with SPDIF already included. I'm interested in easy I2S to SPDIF possibilities if any.

Best regards,

JMF
 
Thanks gwing2,

Good to know. I have now in front, of me several design options to solve my problem.

I would still be happy to understand how to build the SPDIF output from a microcontroller that supports the feature. I understand that it is not just pluging the RCA connector to the STM32 pins...

JMF
 
Hi,

Here is the result of my seach.

I intend to use for first trails a basic schema from the WM8805 (http://www.cirrus.com/jp/pubs/proDatasheet/WM8805_v4.5.pdf)
See below

I got interesting information from AM335x McASP SPDIF output schematic - Sitara Processors Forum - Sitara? Processors - TI E2E Community with a buffer.

All basics in epanorama.net/S/PDIF Interface

I calculated that it should draw 13 mA with a 3.3V powering of the STM32, that seems compliant with the 25 mA limit.

Comments welcomed.

JMF
 

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