Tpa 3122 help

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kkchunghk

Member
Joined 2004
Hi,
I have a simple TPA3122 design and it oscillates. I tried TI for help. All they can say is to follow exactly the evaluation board. I checked that and found that all discoupling cap are SMD and right next to the power pins. My board is all through hole and the caps are 4mm away. Are they not near enough? There is also a space between the inductors and the IC in the evaluation board. Are mine too close? I would also trim the power traces. What else is there that causes the oscillation?
 

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  • TPA3122s bottom (reflected).jpg
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A

aditya

Member
Joined 2007
osilations

hi
i want you to send your bottom layer file and i will make the pcb.. and try i have chip for it , the inductors for it and the CRO to check some thing fishi...
if you do this much as send me the bottom layer in pdf, or post script file or the actual format i can get back to you with a result in 3 days. time
coz even i m after the same amp.. if it work i m goign in for 300W monster by TI, my email id is adityamody@gmail.com
 
A

aditya

Member
Joined 2007
hey i have your pcb lay out but i m soo blogged down with work at office.. i m hardly able to find time to make the pcb but one thing i want to point out is that try giving input to the amplifier and check it
coz i feel your opamps are oscilating, and give it 20volts ie to amp.
 
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