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TPA3251: TPA3251

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Replies: 7

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Part Number: TPA3251

There are three applications (stereo BTL, Single-Ended, and Differential PBTL) in TPA3251 datasheet.

I don't know the connection relationship between a audio jack and INPUT_A/INPUT_B/INPUT_C/INPUT_D in these applications.

  • Hello Genie, 

    What type of output configuration are you targeting? 

    There are different input connections based on the output connection...

    All the best,
    Carolina 

  • In reply to Caro Gomez:

    Dear Sir,

    I want to understand what the input connection is on these three output configurations.

    Best regards,

    Genie

  • In reply to Genie Hsu:

    Hi Genie,

    The jack is a physical connection port. If you look at the Figure 25 on datasheet, which is a BTL configuration has Left and Right two channels, INPUTA/B, C/D should be a differential input pair.

    Depending on your audio source, you have two options, 

    1. Single end input. One jack is enough, Left is connected to INPUT_A, Right is connected to INPUT_C via an AC cap. INPUT B/D should be connected to GND via an AC cap.

    2. Differential input. You need two jacks, one is for LEFT and the other is for RIGHT. L/R on the jack should be connected to INPUT_A/B.

    Regards,

    Sam

  • In reply to Sam(MPAA) Zhang:

    Dear Sam,

    1. Single end input. One jack is enough, Left is connected to INPUT_A, Right is connected to INPUT_C via an AC cap. INPUT B/D should be connected to GND via an AC cap.

    Question: Can I say that LEFT signal from jacket was output to the upper two speakers (refer to figure 26 on datasheet), and RIGHT signal was output  the lower two speakers?

    2. Differential input. You need two jacks, one is for LEFT and the other is for RIGHT. L/R on the jack should be connected to INPUT_A/B.

    Question: MP3 player or smart phine only has one jacket hole, which device has two jacket holes?

    Best regards,

    Genie

  • In reply to Genie Hsu:

    Hi Genie,

    1. No, figure 26 on datasheet is Signle-end configuration which has 4 speakers. In this case, you will need 4 single-end inputs. For this kind of jack, you need two.

    2. Because they are not differential input. They share a common "GND".

    Thanks!

    Regards,

    Sam

  • In reply to Sam(MPAA) Zhang:

    Daer Sam,

     

    1. Single end input. One jack is enough, Left is connected to INPUT_A, Right is connected to INPUT_C via an AC cap. INPUT B/D should be connected to GND via an AC cap.

    Question: according to your connection, LEFT signal was output to speaker A, and RIGHT signal was output to speaker C, am I right?

     

    2. Regarding your answer of my question 2, I can't catch your meaning, sorry.

     

    Besa regards,

    Genie

     


     

     

  • In reply to Genie Hsu:

    Hi,

    1. No, what you post is a single-end output configuration. It has 4 speakers, so the 4 input should be all used independently. 

    2. Let me take an example here. For a jack with 3 terminals, L/R/GND, you have two speaker channels, right? Then INPUT_A connected to L, INPUT_C connected to R, INPUT_B and D connected to GND.

    Thanks!

    Regards,

    Sam