Am Wed, 12 Mar 2014 14:29:16 +0100 hat "Dr. H. Nikolaus Schaller" hns@goldelico.com geschrieben:
Hi,
I am working on the Version 3 prototype schematics and wonder if we
- should use the BQ27500-V130 or could use the BQ27200 (which appears
to need less external components)
Those are for charging, right? Are there any differences in terms of handling?
- find a 600mW replacement for the TPA6110A2 audio amplifier (we have
600mW speakers with 1000mW peak)
The old Pandora one had...?
BTW: we probably can't simply use the same circuit as for the OpenPandora since driving an external headphone with 1W is a little high...
There is a reason for it. Using Pandoras headphones port, you can connect most passive speakers and they are loud enough. With 3DS, PSP, etc., you need another amplifier or active speakers.
Or did the Pandora have less than 1W?
Or should we use a completely different audio codec (like the twl6040?) that has multiple DACs, can driver multiple speakers, headphones and microphones without much external circuitry? The only downside of the twl6040 is that it comes in a BGA package which drives up the number of layers of our main board (because it should NOT go onto the CPU board). Or some other TVL320AIC?
http://www.ti.com/lsds/ti/audio-ic/audio-codec-product.page#o4=ACTIVE&p1...
Any suggestions? Comments?
Since Michael just joined the mailing list and is pretty good with audio, maybe he can help us out here.
The most important thing is that there's nearly no noise or static, neither when connecting headphones or a speaker.
Audio conversion should be pretty good as well. I think the Pandora uses a 24bit DAC, which is what we should also use (at least).
Michael should know more about that as well, and remember what characteristics a good DAC needs to have :)