开云体育

Many of the datasheets I see give a max operating voltage of 15v, including the original ST part
and the?FCI part.? No uBitx with the FCI part has failed, only the WX part.?
All datasheets say 15v Absolute Max (above which damage may occur).

There is no WX datasheet on the web.
Two posts here describe previous experience with some unknown make of TDA2822 clones
that can fail at supply voltages above 7 or 8 volts.
That may well apply to the WX part.
First thing I would do if I had the WX part is order a better part.
I don't know of any FCI parts that have smoked, even when abused with a short to ground.

That datasheet table with speaker impedances shows the maximum supply voltage at
which less than 10% distortion will be experienced for the specified output power.
It does not show when damage to the part will occur.

The datasheet says damage will occur if the Absolute Max supply voltage of 15v is exceeded,
or the output current exceeds 1 Amp, or the device power dissipation exceeds 1 Watt.
With a 12v supply, you might exceed the max current or power dissipation if you crank up
the volume too high with a low load impedance, but otherwise 12v should not damage the device.?
According to the datasheet.?

Reducing the supply voltage to 5v would pretty much eliminate these risks,
and an extremely good idea?if you wish to keep the WX part.
First step is to cut the short trace on the back of the board into the square pad of C76 (near X2).
Then add an LM7805 regulator, pin 3 goes to that square pad of C76,??pin 1 goes to
the feedthrough at the other end of the cut trace, pin 2 goes to ground.
Ideally, add a 0.33uF (or anything from 0.1 to 10uF) cap from pin 1 to ground.
Maybe glue the LM7805 face down onto the back of the board, the leads in the vicinity of C76.

Jerry



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The only TDA2822's that have blown that I am aware of were marked "WX", not "FCI".