• State Resolved
  • Locked Locked
  • Replies 4 replies
  • Answers 1 answer
  • Subscribers 31 subscribers
  • Views 1101 views
  • Users 0 members are here
Support feedback
Options
Options
Related

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.

TAS5756M questions

Gordon Garrity
Prodigy 20 points
Other Parts Discussed in Thread: TAS5756M, TPA6133A2
Hi, we're getting close to final layout and have a few questions:
The TAS5756M has the DAC output exposed for feeding back into the amplifier via an external ac-coupling capacitor, but it may be desired to use the line-out directly as well as the amp. Does the TAS5756M have the same line driver as the 512x part where you can simply hook it up directly to the line output connector via external RC network? If this network is used for filtering out of band noise on the 512x, what is different in the 5756 that doesn't require this network? Is it internal prior to the DAC out pins?
Would you recommend buffering the DAC output if using it to drive line outputs as well as feed back into the amplifier?
Also, we noted that page4 of data sheet has "headphone amp" listed - an error we assume?
Also, if we were to add a headphone amp (we're considering the tpa6133a as we already use this elsewhere) how would you recommend we do so based on the above line out questions?
  • 0
    TI__Guru**** 189401 points

    Hi, Gordon,

    You got it!!! Everything you said is spot on. 

    Thanks for pointing out the error in the d/s, I will log that in the system to be corrected during the next update cycle.

    -d2

  • 0
    TI__Mastermind 34775 points

    Hello Gordon,

    Let me review your use case and provide feedback. As Don mentioned the headphone reference in the d/s is incorrect.

  • 0
    TI__Mastermind 34775 points

    Hello Gordon,

    TAS5756M DAC output has a line driver output, which can handle a min load impedance of 1k-ohms. We would definitely recommend buffering the DAC output when using it as a line driver as it is being shared with the Class D input. TPA6133A2 would be a good  driver, but has 4dB gain (not unity gain). The RC filter network to remove the out-of-band noise from the DAC should be place after the buffer/TPA6133A2.

    The signal from the DAC should be split between DC blocking cap for the Class D input and buffer for the line-out.

    I hope this answer your questions. Please let me know if you have any furhter questions. 

  • 0 in reply to Damian Lewis
    Prodigy 20 points

    Damian, that's great - thanks for the clarification - all good now.

    Gordon