Audio Codec 16-24 bit six output Vs six 16bit DAC

Audio Codec 16-24 bit six output Vs six 16bit DAC Solution

Hi ADI support Team,

I’m Looking to use an Audio codec ( 16 or 24 bit  ) with six output instead 6 DAC ( 16 bit ).

Will be true that using a 6 output Audio Codec like ADAU1328 BSTZ I will get following advantage Vs solution using 6 DAC:

Lower cost, less size, serial bus, highest resolution?

Any drawback?

Is ADAU1328 BSTZ  right choice?

Thanks in advance

Giovanni

  • 0
    •  Analog Employees 
    on May 24, 2016 10:24 PM

    Hello Giovanni,

    This is difficult for me to answer because I know little about your application and your design goals. If cost and PCB size is important then yes, this codec will be a great choice. If you really want the best performance, and you only require DACs, then you could use an ADAU1962 which is a 12 channel DAC. You could invert the signals to the other six outputs and sum them back in giving you a 3dB or so improvement in SNR. But this would be costly.

    The only thing I should mention is that this is an Audio Codec so the input is in 2's compliment and the output is sitting at a common mode voltage level and not ground. So you will require caps on the outputs. Since you only mentioned DACs I am not sure if you were looking at a precision DAC, or other DAC, that is meant for data and not audio.

    This DAC does sample at a high rate for Audio but not when compared to high speed DACs. It is also a continuous time oversampling Sigma-Delta converter. It has no problem with 16 bit data instead of 24 bit.

    Ultimately, It is your application and design constraints that will guide you to the right part. I will be glad to answer any other questions just give me a few more details so I can be more specific.

    Dave T

  • Hi Dave.

    Thank you so much for the fast answer.

    To be precise this in an industrial Application of my customer (RAYTEC VISION S.p.A.,  business dimension  2k pcb per year)

    Solution with ADAU1692 Looks for them very interesting,

    They need 4 ( 6 is better ) high resolution PWMs at max 2 MHz of frequency. To achieve that they think to use 4 ( or 6 ) high speed comparators,

    in which, into the inverting input, there is a 2 MHz triangular wave from about 0 to about 3,3V maximum, and Into the not inverting inputs of each comparator there are connected the output of high resolution DACs, one for channel, so they  can change the output square wave duty cycle, simply changing the output voltage of each DAC.

    In their design the outputs of the DACs would be from 0 to 3.3V, the common mode outputs should be a little complicated because it needs to add differential amplifier … if it is possible and if it works good, but they think the voltage levels should be adapted any way.

    Performances are important not forgetting the cost.

    Can you suggest better choices?

    Best regards,

    Giovanni Galli

  • 0
    •  Analog Employees 
    on May 26, 2016 12:15 AM

    Hello Giovanni,

    The audio codecs we have would probably be suitable but I think you should talk to the folks in our Precision DACs community. Precision DACs

    Ask them the same question and include your application details. I think they may have a better solution for you.

    Dave T

  • Hi Dave

    Thank you for the time you spent for me.

    I’ll address question to the precision DACs forum

    Giovanni