TPA3251: TPA3251 FAULT pin conditon

Vincent Hsieh

Part Number: TPA3251

Dear Sir,

Our TPA3251 use PBTL mode, below is our schematic, the fault pin always is low.
When we open the fault pin, the TPA3251 is available for 150W.
Could you help us check it?
Even if we don't have input, fault pin still is low.

over 8 years ago

0 Diego Melendez over 8 years ago

TI__Guru 57800 points

Hi, Iehncent,

My colleague has been notified about your question, he will get back to you as soon as possible.

Best Regards,

-Diego Meléndez López
Audio Applications Engineer

0 Steve-Wilson over 8 years ago

TI__Mastermind 30220 points

hello iehncent,

I'm afraid I am unable to see your schematic, can you try to post it again?

best regards,
-Steve Wilson

0 Vincent Hsieh over 8 years ago in reply to Steve-Wilson

Expert 1895 points

Dear Sir,

The attached file for your reference.

150w.pdf

0 Steve-Wilson over 8 years ago in reply to Vincent Hsieh

TI__Mastermind 30220 points

Hello Iehncent,

The reset pin (pin 18) should not be connected to the fault pin (pin 19).

see 9.4.6 and 9.4.7 of the datasheet. putting the Reset pin to low, forces the fault pin high.
but in your case, these pins have conflicting behavior because you tie them together. I suggest reviewing the functionality of the Fault pin.

Best regards,

-Steve Wilson

Audio

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TPA3251: TPA3251 FAULT pin conditon