TAS5342A: PVDD max?

Jim Perkins

Part Number: TAS5342A

Max recommended operating PVDD in the datasheet is 34V but the aaplication examples in section 8 show a 36V PVDD. What is the maximum PVDD for TAS5342A and what stops us increasign PVDD >34V for high impedance speakers for an increased output power?

over 5 years ago

0 Shawn Zheng over 5 years ago

TI__Mastermind 24835 points

Hi Jim,
According to the datasheet description, the recommended max PVDD is 34V. We will confirm this and Robert will get back to you later.
Best regards,
Shawn Zheng

0 Jim Perkins over 5 years ago in reply to Shawn Zheng

TI__Expert 3300 points

Thanks Shawn.

Please explain the disparity between the 34V PVDD spec and the 36V application figure. What limits the PVDD max?

Regards

Jim

0 Robert Clifton56 over 5 years ago in reply to Jim Perkins

TI__Mastermind 23090 points

Hi Jim,

Thanks for catching this disparity! I'll look into correcting the datasheet to fix this. I'd recommend sticking to the recommended PVDD voltages in the meantime.

What limits the PVDD max is the output FETs. If the voltage is too high then it risks damaging them.

Regards,
Robert Clifton

0 Jim Perkins over 5 years ago in reply to Robert Clifton56

TI__Expert 3300 points

Hi Robert

Thank you this. Understand the output FETs can be damaged if the PVDD is too high. However, why the large difference between the recommended maximum at 34V and the Abs Max at 53V? The abs max suggested that the FDETs can be damaged if a voltage >53V is applied to PVDD. What if a PVDD of 42V is applied? This should give an 11V buffer without damage occuring. Is it just that the device is only charactersied to 34V so between 34V and 53V there is no guaranteed spec albeit no damage, or are their other specific reasons why the part cannot be used at say 42V PVDD?

Thanks.

Jim

0 Robert Clifton56 over 5 years ago in reply to Jim Perkins

TI__Mastermind 23090 points

Hi Jim,

The biggest reason that abs max is quite a bit higher than the recommended max is due to current. The FETs can survive being at higher voltages but if you are trying to drive speakers at these levels you risk damaging the FETs from the current draw. At our recommended voltage levels, we have tested under normal use conditions that the current shouldn't damage the FETs but the same cannot be applied to the absolute max.

I hope that clarifies things.

Regards,

Robert Clifton

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TAS5342A: PVDD max?