I2S query

[audi0]

I wonder if one of you knowledgeable gents would help me with this query; Is adding I2S to a TDA1543 DAC as simple as tapping into the Data, WS and BCK between the receiver and DAC chips, or am I missing something?

 

[Bill Fuss]

If you are asking, can I use an I2S feed to the dac chip instead of the receiver chip, then yes, but don't try cables for the connection. Keep the wires as short as possible, a few inches is OK.

 

[audi0]

Many thanks Bill, I am planning to switch (probably with relays) between the receiver chip and I2S inputs. Yes the leads will be very short <50mm

cheers.. Steve

 

[Bill Fuss]

I have to get nosey, what are you building? I built a Redbook CD player with an old Magnavox CDM4 player and a Chinese upsampling dac board with outstanding results.

 

[audi0]

Hi Bill, after reading the "Do Audiophiles want a stand alone high end HDD source?" thread, I thought that I would purchase a WD Mini off of ebay and do the I2S conversion suggested by Erin. http://www.diyaudio.com/forums/digi...-want-stand-alone-high-end-hdd-source-14.html
I thought I would build a linear power supply (easier bit) and a daughter board for the reciever chip and relays etc., as I would still like the option of an external SPDIF source as well. Sound OK?

 

[Bill Fuss]

Sounds great. You also have the option of using SS switching instead of relays. There are a number of switching ICs you could use. I was researching these a few months ago and believe they would be more stable than relays. Then my puter crashed, lost my focus. I'll see if I can resurrect some info for you.

 

[Bill Fuss]

Check out Maxim's MAX4754. Small but simple.

Google (quad spdt switching) for others.

 

[audi0]

Thanks for the info Bill, much appreciated. Unfortunately smt and logic circuits are not my strong point!
I guess there would probably be a DIP version? I'll Google it, but I'm not not sure how to switch with logic?

 

[Bill Fuss]

I would imagine someone made them in dip size. Really, they operate just like a relay. One is NC and one is NO, you just switch the power to it on and off with a toggle or whatever.

 

[Bill Fuss]

Vishay DG333A. Runs on 5v, 20 pin dip. Just power the V+ with 5v and the 4 in pins with 5v through a limiting resistor and you are in business.

 

[audi0]

Sweet!

 

[darkfury]

audio0,
I wonder the wiring
from I2S output of usb converter to the place, you connected it where in tda 1543 dac

 

[audi0]

Hi darkfury,

I haven't completed my connection yet, I have a circuit board half finished to combine my DAC receiver IC plus an analogue switch IC so that I can choose I2C or SP/DIF inputs. I'll post photos once completed.
Regarding your query, you will need to break into the circuit board traces between your receiver and converter IC's, something like the drawing below.

Hope this helps!

 

[darkfury]

Thanks a lot of audi0,
Since I have a terralink usb convertor with I2S output(from valab on ebay) just needing to pull out the receiver
I think, We have also have same dac 4*TDA 1543
so, your attempt really interested me
Waiting your results, goodluck

 

[darkfury]

Audi0,
Do I need to desolder CS8412 receiver chip
before connecting the 4*1543's to I2S out?

 

[audi0]

Hi darkfury,
I think it would be advisable yes, but I would be more inclined to cut the tracks rather than remove the whole receiver chip. That way you can easily re-connect if you need to with a bit of solder.
I am adding a switch to mine to select either I2S or SP/DIF inputs, I'll be etching a board soon.