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TPA3255EVM: TPA3255EVM full load test Issue

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Replies: 9

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Part Number: TPA3255EVM

Do we have TPA3255EVM full load test report ?
My Customer offer DC48V and setting PBTL Mode for 2ohm load ,
only get max 300W power output can't get 600W.
In same condition TPA3251 (DC36V) can get 300W power output.

B/R James

  • Hello James,

    • Can you measure what PVDD when your TPA3255 is outputting 300W when it should be 600W?
    • Does it ever reach 600W and ramp down over time or does it never reach 600W?
    • What is the power supply they are using and how much current output is it rated for?

    Best Regards,

    Luis

  • In reply to Luis Fernandes de Pina:

    HI Luis,

    Offer DC48V for full load power on tset.

    600W full load direct jump in OCP => No audio sigle output.

    DC source 48VDC/20.8A.

    B/R James

  • In reply to James Su5:

    Hello James,

    How are you reading your output power?

    What are you using for your input signal?

    Did you double-check your jumper configuration for PBTL as specified in the User's Guide?

    I just tested the TPA3255EVM with your test conditions and I was unable to replicate your results

    Best Regards,

    Luis

  • In reply to Luis Fernandes de Pina:

    HI Luis,

    In DC48V 2ohm load can get max 600W potout ?
    setting as below pic, may I miss some thing (setting)?

    B/R James

  • In reply to James Su5:

    Hi James, 

    We were under the impression that they were testing the EVM and not their own board. This leaves me to ask the follow questions:

    When they say they can only get 300W output, is the device entering OTW or Fault? 

    Is the heatsink they are using similar to the same size as the one on our EVMs?

    What is inductors that they are using? 

    Regards,

    Robert Clifton

  • In reply to Robert Clifton56:

    Hi Robert,

    They test EVM and their own board both and get same test rule.
    Not OTW , and heatsink size bigger then EVM size
    they remove EVM inductors on their own board ,still no 600W power output.
    2ohm / 4ohm / 8ohm on PBTL also can get max 600W Power output , right ?

    BR James

  • In reply to James Su5:

    Hi James,

    So I ran some calculations using your power supply and realized that they will not be able to reach 600W due to current limitation from their power supply. I'm assuming that they used the same power supply to test the EVM? 

    Now based on my calculations if all of the current went straight to the device they would only get about 459W (10% THD) of output power. 

    Do they have a different power supply that's able to output a higher current that they can test this on to see if this is the issue? It's still a bit strange that they are only able to get 300W of output power instead so there might be something else going on here or the other components on their board are consuming a lot more than believed. 

    Regards,

    Robert Clifton

  • In reply to Robert Clifton56:

    Hi Robert,

    So, EVM offer 48V 20.8A DC source and 2ohm resistor only get about 459W, right ?
    What is power source condition can get 600W po? ex DC53V / 20A or DC48V / 30A ?
    We need to check they have a different power supply that's able to output a higher current or not .

    Regards,

    James

  • In reply to James Su5:

    Hi James,

    Based on my calculations, the output power was calculated to only get to 459W. The limitation that I think they are hitting is a current limit and not a voltage limit. So DC48V/30A would be the way to go.

    Best Regards,

    Robert Clifton