Audio amplifier Mono to Stereo

Discussion in 'General Electronics Chat' started by pivic, Jan 20, 2014.

  1. pivic

    Thread Starter New Member

    Jan 20, 2014
    Hello all,

    I have attached the audio stage of my design.
    The TDA8541 is fed by a DAC 0-3.3V.

    In normal use the sound will go through the 8 Ohms speaker but I want the possibility to plug headphones or speakers. I don't need to be in stereo but I want both ears/speakers to be working if a stereo jack is plugged.

    The way it is currently wired works but I wonder if it would be better to connect the sleeve of the jack to ground instead.
    The down side of doing such thing is that I would have an external lead connected to the ground and therefore possibly acting like a point of entry for noise... But on the other hand I don't want to damage headphones/speakers.

    How would you do it?

  2. ericgibbs

    Senior Member

    Jan 29, 2010
    Look at this clip from the TDA d/s, it shows that Out- is NOT at 0V, I would advise against connecting the jack sleeve to Gnd.
    If the setup works OK as you have said, leave it that way.
  3. pivic

    Thread Starter New Member

    Jan 20, 2014
    hi ,

    Thanks for the reply.

    Yes I know that the OUT- is not internally connected to GND. My idea was to disconnect the sleeve from OUT- and connect it to GND. The Speakers/Headphones would therefore have only one signal fed to them, and the on board speaker would still have the full swing of the BTL output.

    It looks like it works but I'm a bit worried some speakers/Headphones would get damaged if they get a signal in the sleeve? like it is in my current design.