TAS1020A vs PCM270x

[DragonMaster]

There's a simple device made by AudioTrak (OPTO Play) using the TAS1020A with an external DAC to get USB 24/96 audio. Wouldn't this be a better alternative to the PCM270x? (It can also support multi-channel and recording)

 

[DaMeat]

The TAS1020A doesn't have an easy I2S output, so you would have to code it into the uController... or maybe ask Audiotrak if they will give you their code

PCM270X is just so easy to interface to a DAC, but if you are good at coding and want to spend lots of time writing... go for it. I would love to use the result, add my own code to the uController to run other various things off USB (Like a display, or power switches, or ...???) but I don't want to take on the task of interfacing this to a DAC.

 

[DragonMaster]

I looked at the datasheet, the only thing you have to do is to use an HEX editor to make a ROM file, program it on a serial ROM and connect it to the TAS1020A. Everything's in the datasheet.

 

[DaMeat]

OK, this chip looks interesting... Let me tell you the problems I see.

1) Interface an EEPROM to the chip (No big deal, but another part)
2) Program the EEPROM when the MCU boots the first time, using windows DFU protocol (Actually this is nice because you could upgrade this to do more right in Windows)

3) The big one, where is the firmware? Maybe if you ask TI they will give you the EVM board firmware, or even better point you to the 4 channel firmware... I can't find it on TI's site, and it looks like they moved on to better chips?

Which leads me to this chip:
TUSB3200

Now it has 8 channels, supports several I2S streams and even seems to have a firmware development kit you can download. I would be willing to help with this project, sounds fun...

For ease of building the TAS1020A is so simple and needs almost nothing... just plug it into your USB and i2S comes out

 

[DragonMaster]

But the problem with the TUSB3200 is that it requires a lot of C programming. The TAS1020A only needs a few HEX numbers.

 

[DaMeat]

Only needs a few HEX numbers? Maybe for USB ID and standard things, but I2S out with multichannel doesn't look like a few HEX numbers to me. You need the firmware from them, but I don't see it anywhere... point it out to me and I will have a look.

Also, the PCM270X is supposed to have much less jitter(?) than the achronous (? did I get the spelling right) that these chips output.

Find the firmware, and I think you will find the TAS1020A needs quite a bit of programming (Also the TUSB3200 gives you examples to start from, so it would really just be code editing and not lots of C writing).

 

[gene_klein]

This link gets you to the Firmware Development Kit for the TAS1020

http://focus.ti.com/docs/toolsw/folders/print/tas1020fdk.html


gene

 

[lucpes]

A faster alternative would be to buy an M-Audio Transit USB and tap I2S from the DAC lines in there. Did not try it but should not be too much fuss... supports 24/96 as opposed to PCM270x.