What is the maximum voltage to be shown at CN10 Audio Output on DK1/DK2 boards ??

[Imen.D]

Hello @RGarc.3​,

Welcome to the STM32 Community :)

Which device are you using ?

Imen

[RGarc.3]

Hello Imen,

I'm using an STM32MP157C-DK2.

Please see attached image for further details.

Thank you very much for your helping.

Rafael.

[Imen.D]

​Hi @RGarc.3​ ,

I updated the topic of your question and added the right one related to "STM32 MPUs" to increase the chances of getting you a reply from our experts and community members.

Hello @Community member​ ,

Can you please help  @RGarc.3​  on this question ?

Imen

[Jean-Marc S · Accepted solution]

Hi @RGarc.3 (Community Member)​ ,

Some information can be found in the User Manual fo the board on st.com

https://www.st.com/resource/en/user_manual/dm00591354-discovery-kits-with-stm32mp157-mpus-stmicroelectronics.pdf

           Operating voltage

The audio codec has two power supplies:

• VL, connected to the 3.3 V provided by the STPMIC1

• 1V8_AUDIO, dedicated 1.8 V source provided by the STPMIC1

Headphone outputs The STM32MP157A-DK1 and STM32MP157C-DK2 Discovery kits can drive a stereo headphone.

The STM32MP157x sends the stereo audio channels to the codec via its SAI2 TDM port. The codec converts the digital audio stream to stereo analog signals. It then boosts them for direct drive of the headphone connected to the CN10 3.5 mm stereo jack receptacles on the board.

The audio codec is set by an I2C bus. The address is a 7 bit address plus one bit for read/write (high for read, low for write). The AD0 pin, connected to GND, gives the least-significant address bit. The address of the audio codec is 0b1001010x: 0x94 to write and 0x95 to read.

The audio codec component used on this board is the CirrusLogic CS42L51-CNZ

The CS42L51-CNZ datasheet can be found on the web and shows:

So programming HP_GAIN[2:0] at @08h will provide the gain setting and Vpp voltage range.

Default is HP_GAIN=011 à Gain=0.6047 à Vpp = 1.48V

JM

[RGarc.3]

Hi JM,

Thanks a lot for helping.

It was a bit dificult to me getting the information from the "document forest" about this device, even more taking in consideration English is my 3rd language...

Once more,

Thanks for helping !!!