Hello everybody, I created my own amp with TDA 7297 IC.
Now I had a problem. It has some noice.when i touch the heat sink, the noice has decrease.
I don´t think or prefer to repair it less of noice , coz it is an amp.
But I still wanna decreases the noice without touching the heat sink.I tried to ground it, but it has no change.
But When i touch heat sink, noice has decreased.
Please help me. :-D

 

Is the noise hiss or hum (high or low frequency)?
Are you using a switch-mode power supply?

 

Is the noise hiss or hum (high or low frequency)?
Are you using a switch-mode power supply?

No I didn´t use any power supply.
I used only 12V 1A Adaptor for power supply.
There is no switch sir.

 

Hello everybody, I created my own amp with TDA 7297 IC.
Now I had a problem. It has some noice.when i touch the heat sink, the noice has decrease.
I don´t think or prefer to repair it less of noice , coz it is an amp.
But I still wanna decreases the noice without touching the heat sink.I tried to ground it, but it has no change.
But When i touch heat sink, noice has decreased.
Please help me. :-DView attachment 107837

Did you follow pcb layout advice s described in datasheet?
I smell oscillation.
Is your pwrsupp able to deliver 2 x15W + overhead caused by the circuitry?
Please connect a scope and observe the output.
Picbuster

 

Is the noise present when you have a signal source properly connected to the input, or only when the input is floating (open circuit)?
What is your signal source?

 

What's it like when you power it from a 12v battery?

 

Is the noise present when you have a signal source properly connected to the input, or only when the input is floating (open circuit)?
What is your signal source?

Both condition sir.

 

What's it like when you power it from a 12v battery?

No I didn´t try this way.
I´ll have to try so..
Thanks