TPA3122 works fine on battery - starts clicking on powersupply.

[Cyberzim]

Hello,
I have made a nice TPA3122 amplifier, but still on breadboard right now. It works perfekt with my batterypack.
When I use it on my supply it start clicking like it's turning on and off all the time.
I have 2 x 2 4700uF capacitors(2 pairs in serial connection) on the supply and 2 x 470 uF on the breadboard.
Do I need to add something for more stabelised supply?

Thank you,

Simon H.A.

[theAnonymous1]

More information?

Supply type (linear or switching)? Voltage?

[Cyberzim]

It's rated 18VAC @ 2,78A and when converted to dc it is at 27V no load.
My supply is a transformer, dual primaries and secondaries in serielconnection.

[Eva]

But what are the battery and the power supply voltages? The latter may be too high.

Also, it could be an EMI issue.

[Cyberzim]

Batteri is at 22V fullcharged. As I said the supply is 27V DC. The chip is rated for a maximum of 36Volt.
What does EMI stand for?

[Cyberzim]

Hm... I have charged my batterypack and now it also start clicking when I turn up for the volume.

Regards,

Simon H.A.

[Cyberzim]

I think it's stability problems since it sometimes on high volume first start the clicking thing and then it start making a high pitch noise and wont stop until I turn the volume down or disconnect power and connect again.
So I have made a pcb layout. I have added 2 x10uF and 2 x 100uf elecrolytic in serial-connection, because I think it could help with the stability and it also provides the speakerground.
I would be pleased if you could give some feedback on my layout. I'm willing to change the whole layout if it will give me better results since this project means a lot to me.

Thank you,

Simon H.A.

[theAnonymous1]

What type of caps are you using for the smaller caps (1uF,0.1uF,0.22uF)?

[Cyberzim]

I'm using ceramic caps.

[sexya]

Originally Posted by Cyberzim

I think it's stability problems since it sometimes on high volume first start the clicking thing and then it start making a high pitch noise and wont stop until I turn the volume down or disconnect power and connect again.
So I have made a pcb layout. I have added 2 x10uF and 2 x 100uf elecrolytic in serial-connection, because I think it could help with the stability and it also provides the speakerground.
I would be pleased if you could give some feedback on my layout. I'm willing to change the whole layout if it will give me better results since this project means a lot to me.

Thank you,

Simon H.A.

hey simon
i think you have missed out on the out put inductor in series with a electrolytic capacitor, on the out put side,
and your two grounds are to be made one at one point so have alook in to it,
i mainly feel its your dc blocking caps and the inductors that are missing. check the datasheet diagram properly,
if you want to try i have some design , let me know if you want to make the pcb i will mail you the desing i havent tried it so cant say and its from a fellow on the forum