TPA3111D1 no audio output for input voltage more than 27V.

[vikash23]

Hi,

I could not able to get audio output when the input voltage of PVCC goes beyond 27V. Since the operating condition is 26V I am using a battery which can deliver +or- 27V. What is the best method to get the out put for more than 27V input ?

Can I split the voltage rails for SD,FAULT,GAIN,AVCC and another rail for AVCC ?

AVCC goes into the LDO which stop the amplifier giving the output for input more than 27V ?

Thank you.

Awaiting your reply.

 

[Audioguru]

The input to this amplifier IC is an audio signal, not the DC supply voltage.
The maximum recommended supply is 26V, DO NOT use a battery that can deliver + and - 27V which is a total of 54V.
If your supply voltage is more than 26V then maybe the IC is overheating and is shutting down.

 

[vikash23]

Sorry,

+ or - 27 volt , I mean the tolerance. it can be with 27.5 or 26.8.

IC is not over heated and my IC is shutting down just for the input voltage of 27.1V. If i turn the voltage down to 27V it works fine.

I posted this problem in TI forum and they came with a suggestion to step down the battery voltage to 26V. I hope I need to follow their suggestion.

 

[betwixt]

The data sheet quotes a maximum operating supply voltage of 26V with an absolute maximum of 30V. The absolute rating is the limit of no return befoe damage occurs, it doesn't mean you can safely use the IC up to that voltage.

Add one or more silicon diodes in series with the supply rail, each will drop around 0.7V so add enough to keep the supply below 26V.

Brian.