Hi,
I'm looking to plan a project where I take my stereo line in, into a pre-amp / source selector, and then possibly output the stereo audio to a USB headset via a ADC with USB capabilities.
I had a look at the PCM2903 chip and at first glance, this might be what I need. However, with the USB side of things, it appears (to my amateur view) that I would need a USB host in order to configure the PCM2903 chip once it is powered on. My reasoning is that in the datasheet under section 9.3.1 it appears as if the control endpoint is the default, and it may need configuring so that it uses the correct config for endpoint #4 (which seems to be digital out via USB).
Is this really the case?
Did I mis-understand the datasheet and it's in fact just a power-on and play device?
Thanks
I'm looking to plan a project where I take my stereo line in, into a pre-amp / source selector, and then possibly output the stereo audio to a USB headset via a ADC with USB capabilities.
I had a look at the PCM2903 chip and at first glance, this might be what I need. However, with the USB side of things, it appears (to my amateur view) that I would need a USB host in order to configure the PCM2903 chip once it is powered on. My reasoning is that in the datasheet under section 9.3.1 it appears as if the control endpoint is the default, and it may need configuring so that it uses the correct config for endpoint #4 (which seems to be digital out via USB).
Is this really the case?
Did I mis-understand the datasheet and it's in fact just a power-on and play device?
Thanks
I'm sure you're correct - you need a USB host to 'attach' to the chip before it'll function. Your USB headset is almost certainly the same, it'll be a USB device in need of a connection to a host.
Have you considered using an analog headset? That would avoid the whole ADC -> USB -> DAC conversion.
PCM2903 cannot be the host, it is device only, so it is not possible to connect use it to output the stereo audio to a USB headset.
That's what I was thinking. Sadly.
My alternative is to see if I can source a USB bridge / hub chip, and have it enabled / powered on when I select USB on the output selector for my project.
The USB could just be a hub / pass-through that then connects to my PC.
My alternative is to see if I can source a USB bridge / hub chip, and have it enabled / powered on when I select USB on the output selector for my project.
The USB could just be a hub / pass-through that then connects to my PC.
I suppose without a USB hub switch, I could just have a solid state switch of some sort to disconnect the USB device, right?
When selecting the output source as USB, I could just enable a USB hub / switch so that the signal path is:
PC --(USB)---> My new preamp input/output selector -> USB Headphones
When selecting the output source as USB, I could just enable a USB hub / switch so that the signal path is:
PC --(USB)---> My new preamp input/output selector -> USB Headphones