Hi,
I hope the Question is not to stupid and I’m in the right Subforum.
I’m looking to drive 3-4 Channels per Speaker Box with an AMP that’s fed with PWM at 384kHz (352-500kHz).
Is there any Way to either use ADAT or files/network to get directly to a good PWM Output for a Power Stage?
I mostly see: X -> I2S -> PWM -> PowerStage
Is there a μC with direct Output of 3+ PWM Channels that are good enough to be directly fed to the PowerStage?
TI has three "eHRPWMs" in their AM335X Sitara. Would they suffice or is there some special reason to add a I2S-to-PWM Chip?
I guess I need at least Hardware PWM and DMA to even consider it for Audio?
The Sitara could receive ADAT, use a Network and access local Files.
(Additionally the Sitara even has DSP Functions.)
48kHz@16bit is needed and 96kHz@16bit would be nice.
I guess I won’t hear any Difference for higher Sample Rates or higher Bit Depths.
Thank you very much.
I hope the Question is not to stupid and I’m in the right Subforum.
I’m looking to drive 3-4 Channels per Speaker Box with an AMP that’s fed with PWM at 384kHz (352-500kHz).
Is there any Way to either use ADAT or files/network to get directly to a good PWM Output for a Power Stage?
I mostly see: X -> I2S -> PWM -> PowerStage
Is there a μC with direct Output of 3+ PWM Channels that are good enough to be directly fed to the PowerStage?
TI has three "eHRPWMs" in their AM335X Sitara. Would they suffice or is there some special reason to add a I2S-to-PWM Chip?
I guess I need at least Hardware PWM and DMA to even consider it for Audio?
The Sitara could receive ADAT, use a Network and access local Files.
(Additionally the Sitara even has DSP Functions.)
48kHz@16bit is needed and 96kHz@16bit would be nice.
I guess I won’t hear any Difference for higher Sample Rates or higher Bit Depths.
Thank you very much.
The PWM needs to be done in the amplifier because the PWM needs to include negative feedback from the speaker. This handle loading issues and the power supply noise cancelation. Consider that the output is the product of the PWM and the power supply voltage. Any ripple voltage on the power supply will modulate the audio. Put another way class-D amplifiers have no power supply rejection, none, unless the amplifier includes feedback that compares the output to an analog input.
LOL! You should do your homework. Look at the TI data sheet and you will see that the input "PWM" is converted to analog, compared to the feedback, and then converted to a different PWM that drives the output.
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If you have no answers don’t answer…
The Internals are completely irrelevant.
They take a PWM Signal and I need to supply one.
Has someone a Tip for a μC with a suited PWM Output?
The Internals are completely irrelevant.
They take a PWM Signal and I need to supply one.
Has someone a Tip for a μC with a suited PWM Output?
In post #1 you wanted the PWM to directly drive an output stage and now you don't mind if it is converted to some other PWM signal that drives the output stage. Right...
Then PowerStage is the wrong translation for it.
I’ll have some TAS5631B Boards that need to be fed with PWM.
I’ll have some TAS5631B Boards that need to be fed with PWM.
The I2S->PWM part could be handled by a Zoudio amplifier board. Just remove the output filter L and C, I'd assume a direct connection to the "PowerStage" is then possible, particularly if that's another TI product - at least you could legitimately bug TI's support about it. The Zoudio uses TI's TAS5825. Internal to it is I2S->PCM->PWM - with DSP available in between as a bonus.
There's a thread here in https://www.diyaudio.com/community/...dsp-and-bluetooth.347637/page-33#post-7053792 Good Luck; it'll be interesting if you go this route.