TPA3255: TPA3255 current protection

Hi Eddie,

Can you give me more details? Is the device in pre-filter PBTL, or post filter PBTL? If possible, can you share the schematic? 

Thanks,

Robert Clifton 

Hi Robert,

Please refer to customer schematic attached.

Hi Eddie,

Ok so this is pre-filter PBTL  mode. Do you know what the current rating of the inductors are? 

Also one thing that is very strange to me is the inclusion of C14 and C31. Why did the customer's include these capacitors? 

Regards,

Robert Clifton

Hi Robert,

Customer is refer to our reference circuit below, should they need short the jumpers for hi current?

http://www.ti.com/lit/df/slar129a/slar129a.pdf

Thanks & Regards

Eddie

Hi Eddie,

Are you talking about the jumpers for the electrolytic capacitors on the output? 

Were you able to find the current rating for the inductors?

Regards,

Robert Clifton 

Hi Robert,

The current rating of inductors  are 15A, and c14 c31 are use for DC coupling.

Thanks & Regards

Eddie

Hi Eddie,

C14 and C31 are only really needed in SE mode. In PBTL and BTL, the DC bias on both full bridges are PVDD/2 so from the transformer, it doesn't see any DC bias point. My biggest concern with including these capacitors is it creates an high pass filter that might be cutting off the frequencies you are wanting.

Regards,

Robert Clifton