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.

  • TI Thinks Resolved

TPA3255: TPA32XX single-ended input stage

Prodigy 180 points

Replies: 6

Views: 258

Part Number: TPA3255

Hello, when i design a pcb for a tpa32xx serie chip, can i without any problems (just i assume i should get i get a weaker output signal as stated) connect the A and D inputs to a single-ended source in BTL mode (A pin to right channel input and D pin to left channel input) and B and C pins to dc blocking capacitors of an equal value than the A and D pins (10uf) to ground (like it is possible with tpa3116 amplifier or tpa3220/3221 amplifiers)?

Or did i am forced to use a single-ended to differencial output converter made with op amps (that increase the cost and degrade the sound quality but allow me to get the full output power and; maybe depending by the noise floor level of op amps, to get less output noise, because the inputs are differencial)?

Thanks

  • Hi Lulu,

    Sorry for the delay as my colleague who is responsible for this device is not available. We are looking into this issue and will get back to you as soon as possible.

    Regards,
    Alix Wan.
  • In reply to Alix Wan:

    Hi Lulu,

    Yes you can input SE inputs into A and D inputs, but you will sacrifice half of the output voltage capability. In order to use the full output power in BTL, you will need a differential signal on the input.

    TPA3221/0 and TPA3116 is able to change the gain so that you can get back to the same output power with SE signals. TPA325x and TPA324x are fixed gain.

    Justin
  • In reply to Justin Bohr:

    Ok, but i think that i will get a better sound quality with a tpa325x/324X based amplifier? Also, did a air core inductor provides a better sound quality than magnetic core ones?

    Thanks

  • In reply to Lulu Lulu:

    Yes the TPA325x/4x will have better audio performance. An air core inductor should be more linear in its behavior over power and frequency, providing better THD performance.

    Justin
  • In reply to Justin Bohr:

    Hello, i see that the tpa3245 is the best oriented chip for the way i want to build my prototype, (by some of the facts that ouput noise at the lowest of tpa324x/325x family and output power and entry impedance perfectly fit to my needs). But the problem is that output impedance must be 4 ohm max (as show on the datasheet), but, can i use 8 ohm speakers (as i wouldn't use the chip until it reach max output power and will use 32v main supply) ?

    Thanks

  • In reply to Lulu Lulu:

    Hi Lulu,

    Using a higher impedance speaker is actually fine. You just won't be able to get as much power into the speaker.

    Best Regards,
    Robert Clifton

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.