Other Parts Discussed in Thread: TPA3001D1,
Hi,
I was able to send 12 dB audio through the headphones from the Colibri 3.2 eval board
as an input to the TPA3612D2EVM. I used a sound meter and the sound from the demo
is comparable to the sound from the existing application.
The remaining part is to figure out is the filter at the output of the power amp. Some distortion
in the audio is heard.
I have attached the audio interface schematic used in the existing application. I tried soldering the power
amp output directly to the low pass filter (disconnecting the old class D from the existing application).
This test did not work so well, some component smoked on the existing application board which means the
loudspeaker is possibly being overloaded.
The EVM and new class D design is powered by 12V. This puts the voltage at the PLIMIT at 5V. Given
a 4 Ohm 3W loudspeaker, should this voltage be reduced to 3.4 V to avoid speaker overloading?
Can the same LC filter be re-used at the output of the new class D part before entering the relay switches?
Is there benefit to viewing signals on the scope? I have a function generator I can use to send 0.2 V rms
to the power amp EVM directly and I can see this signal on the scope. What outputs from the EVM to I
connect to the scope to view output amplitude/and distortion?
Thanks,
Priya
ICoreDigiAudio.pdf