Re: Switching Regulator for Audio Amplifier

On Sep 15, 3:15 pm, "Paul Hovnanian P.E." <p...@xxxxxxxxxxxxx> wrote:
Fred wrote:

I have an audio amp based on the LM3886. In order to get 50W out of
it I need to use a transformer who voltage rises too high for the
LM3886 to tolerate during no or light load times.

I have modeled a linear regulator for the amp, but is is very
wasteful, it dissipates over a hundred watts a channel. I had to
parallel four regulators on each rail in order to keep their
individual dissipations manageable.

I have started considering a switched mode power supply, and have been
looking at chips such as the LM5116. Some time ago, I heard using
SMPSs in audio amplifers in problematic because of the difficulty in
filtering out the switching noise from the output.

Any suggestions would be appreciated.

FB

What's the state of the art in terms of Class D (or other PWM
architecture) audio amps in this power range?

Perhaps you could give up the idea of trying to clean up the supply for
a linear amp and really save yourself some power.

--
Paul Hovnanian p...@xxxxxxxxxxxxx
-----------------------------------------------------------------------
Have gnu, will travel.

I think this problem is solved. I just have to verify that by buying
a $130 transformer and a couple mnore filter caps.

I actually have a chip set for a class D amplifier. Like the discrete
design it significantly more elaborate. Looking to the future
though...

Fred
.

Relevant Pages

  • Re: Switching Regulator for Audio Amplifier
    ... LM3886 to tolerate during no or light load times. ... it dissipates over a hundred watts a channel. ... filtering out the switching noise from the output. ... used a common mode filter transformer at the output of the SMPS to get ...
    (sci.electronics.design)
  • Re: Switching Regulator for Audio Amplifier
    ... LM3886 to tolerate during no or light load times. ... filtering out the switching noise from the output. ... Several years ago I designed a class-D amp with an off-line SMPS. ... used a common mode filter transformer at the output of the SMPS to get ...
    (sci.electronics.design)
  • Re: Switching Regulator for Audio Amplifier
    ... LM3886 to tolerate during no or light load times. ... filtering out the switching noise from the output. ... Several years ago I designed a class-D amp with an off-line SMPS. ... used a common mode filter transformer at the output of the SMPS to get ...
    (sci.electronics.design)
  • Re: Switching Regulator for Audio Amplifier
    ... it I need to use a transformer who voltage rises too high for the ... LM3886 to tolerate during no or light load times. ... You need a transformer with better regulation and probably larger filter ... The loop response times of many switching regulators simply isn't good ...
    (sci.electronics.design)
  • Re: Switching Regulator for Audio Amplifier
    ... it I need to use a transformer who voltage rises too high for the ... LM3886 to tolerate during no or light load times. ... You need a transformer with better regulation and probably larger filter ...
    (sci.electronics.design)