Using DRV8662 amplifier only

Hello Alex,

Thank you for looking at the DRV8662! The amplifer is driven off of the boost voltage so using the higher voltage will still work with the amplifer section.  However, other parts of the circuit will need to be driven off of Vdd.

- Will you be able to still provide 5V to Vdd?

- What is the reason to not use the boost converter?

Thanks Rodney,

Yes, I can provide 5V to Vdd. And just leave SW, Vbst, Vpump, FB and REXT floating - right?

Reason for considering this approach is that boost converter runs at fairly low frequency and noise in the outputs generates an audible "hiss" with the type of actuators I am using. Filtering and tinkering with L,C values helps but problem still persists.

Regards,

Alex

Alex,

I'm not sure that you can float those because they are part of a feedback loop for the boost converter and will be in an unknown state. Let me look into this a little bit to see what we can do to help with the "hissing".

Rodney-

Thanks for your help. I do not really care about the state of converter assuming there is no impact on the rest of the chip but having better knowledge about 8662 internals would help certainly.

As for the switching noise - it is our 3rd design using 8662 with the same result - hence  looking at external PS options.

Regards,

Alex

Excellent. Thanks Rodney

/Alex