|
Home | Forums | Rules | Articles | diyAudio Store | Blogs | Gallery | Wiki | Register | Donations | FAQ | Calendar | Search | Today's Posts | Mark Forums Read | Search |
Digital Source Digital Players and Recorders: CD , SACD , Tape, Memory Card, etc. |
|
Please consider donating to help us continue to serve you.
Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving |
![]() |
|
Thread Tools | Search this Thread |
![]() |
#1 |
diyAudio Member
Join Date: Aug 2009
|
![]()
I'm making a DAC for myself and am laying out the pcb at the moment. I have a couple of final questions I'm hoping the experts here can help out with:
- Does the 1704 benefit from having seperate analog/digital supplies (though grounded together)? The datasheet says it doesn't but I'm not sure whether to believe it. - What's the best value of capacitance to use for the BPO/Servo/Ref DC caps? I've seen some boards use different values than the recommended ones, and some say to use as large caps as possible. - Also, a sub-question, do these DC caps need to be as close as possible to the chip like the bypass caps or is it ok for them to be a little further out? - Does anyone out there have any app notes or any other good info for this chip? I've seen a diagram or two floating around but TI won't supply me with anything since I'm just a diy hobbyist and not Denon or something ![]() Thanks for reading. |
![]() |
![]() |
#2 |
diyAudio Member
|
There should be some manuals for evaluation boards on the web site that contain schematics and/or board layouts. They may not be specifically for the PCM1704 -- they might be for another related component and happen to use the PCM1704 DAC. Study these
__________________
bel |
![]() |
![]() |
#3 | |
diyAudio Member
Join Date: Nov 2009
Location: Los Angeles
|
Quote:
G² |
|
![]() |
![]() |
#4 |
diyAudio Member
Join Date: Oct 2003
|
Have a look at the implementation from Nagai-san of Denon :
Tefron PCB using VISHAY Z-Foil Registers Patrick |
![]() |
![]() |
#5 | |
diyAudio Member
Join Date: Nov 2008
Location: Australia
|
Hello, you may benefit by looking at the thread
Silicon Chip DAC kit as this can be used accross BB/TI Dacs, we have endevoured to explore all possibilities for improvement at a conservative outlay Alfred PS and also http://rockgrotto.proboards.com/inde...ad=4477&page=1 Quote:
Last edited by alfredrofe; 22nd January 2010 at 04:48 AM. |
|
![]() |
![]() |
#6 |
diyAudio Member
Join Date: Aug 2009
|
Thanks for the replies.
I have the eval kit datasheet for the 1704, it's been quite helpful. The thing is that it isn't stated anywhere whether the specs in the 1704 datasheet are actually achieved by the eval board. I doubt that double layer board gets -120dB noise, and that puts the other specs into doubt also. So really I don't know whether I should follow it and risk getting only "sufficient" specs. I saw that teflon board earlier as well and it raised more questions that it gave answers, unfortunately. For example, why does he use much larger size caps? Why metal-film bypass instead of ceramic when ceramic has lower impedance AFAIK? Also, he uses lower impedance reservoir caps, which would cause a much larger anti-resonance impedance in parallel with the smaller bypass caps. I wish there were some measurements to confirm the performance of the board. BTW I hope it doesn't come across like I'm whining here, because I'm actually really enjoying all of this ![]() |
![]() |
![]() |
Thread Tools | Search this Thread |
|
|
![]() |
||||
Thread | Thread Starter | Forum | Replies | Last Post |
PCM1704 I/V response | scobham | Digital Source | 5 | 11th September 2008 04:32 PM |
PCM1704 @ 192Khz possible? | jeje | Digital Source | 6 | 19th July 2008 08:55 PM |
Pcm1704 | hacknet | Digital Source | 5 | 11th April 2004 09:25 PM |
What outputstage should you use with PCM1704 | Ryssen | Digital Source | 0 | 6th January 2004 05:20 PM |
schmetic of pcm1704 | takashi | Digital Source | 19 | 26th November 2002 07:17 AM |
New To Site? | Need Help? |