This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

PCM1774: Compatibility with BeagleBone Black

Part Number: PCM1774

Good morning,

I am currently doing my master thesis in TU Delft and I was thinking of using the PCM1774 as a dual audio DAC to convert the audio data coming from a mini SD card through the microcontroller BeagleBone Black. Do you know if it Beaglebone and PCM1774 are compatible?

Thank you,

Alessandro

  • Hi Alessandro,

    I am not aware of any particular device compatibility issues.  Really the most important thing to know is if the MCU supports and I2S datastream.  I2S is a standard digital audio format, so you will need to check if you can get an I2S stream from the SD card in the MCU.  If you can do that, then you just have to connect the data to the PCM.  The PCM1774 also has some digital control interfaces (I2C or SPI), but that should be pretty easy with the beagleBone.

    Thanks,
    Paul

  • Thank you very much for your answer.

    I would like to ask you another thing if possible. What happens if I connect both the earphones to the same output (either left or right)? Do I get a mono earphones configuration or it simply does not work?

    Indeed, in my project I should send one of the 2 stereo output signals to an audio device (earphones) and the other one should take another path towards electrodes for electrical stimulation.

    Thanks,

    Alessandro

  • By connecting both headphones to one output you just halve the impedance.  You will need to take the maximum power output of the DAC into consideration.  This device is rated for 40mW into a 16Ω load.  You should verify the impedance of your headphones does not violate this.

    Thanks,

    Paul

  • Thank you again. And what happens if the system clock of the microcontroller is 48 MHz? Is it too high?

  • That clock rate violates the maximum specified clock rate.  I do not think you could guarantee operation.