A quite erroneous schematic need to be fixed

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Hello

What i want to do is to convert the 0.6V spdif to 3.3V TTL so it can match to the input of the ES9018k2m
An optical receiver i suppose that can directly feed the ES

I have tried a dvd-player, it locks only for a second
The PC Spdif output taken directly from motherboard works fine

Some sources i've found
http://noel.loutre.free.fr/autres_simulations/spdif-coax_vers_ttl_0-5v/spdif_ttl.htm
S/PDIF signals converting - Konverze sign?l? S/PDIF
S/PDIF Digital to Analogue Converter

And this is how my imagination works
ttl.jpg

R1 is the 75 Ohm termination, C1 blocks any DC
R5,C2 the same as above for the secondary
R2 i dont know its job, just copied from an other scheme
R3,R4 is a Vcc/2 divider for something like bias
And the buffered inverter is just buffering
 
Hi, so if I understand correctly you just want a coax SPDIF input on your ES9018k2m DAC?

That is correct
To be more specific i want flexibility so i can try every kind of source (Toslink, spdif, TTL). The differntial AES i suppose is meaningless as the DAC's input is single

I believe that working with isolated from ground power supplies will reduce any noise or loop coming from ground by the external sources. Just thoughts
 
Last edited:
Disabled Account
Joined 2002
Believing should be done in church �� I have used many SPDIF transformers and they are needed in many cases (but not all).

Mainboards of computers carry many signal lines without any transformer ;-)

Anyway, I think you should start with 150 Ohm across primary and secondary windings.
 
Last edited:
Believing should be done in church �� I have used many SPDIF transformers and they are needed in many cases (but not all).

Can you please mention a couple cases that it is needed and/or not? So, do you think i should make the converter twice, one isolated and the other without?


Mainboards of computers carry many signal lines without any transformer ;-)

Indeed

Anyway, I think you should start with 150 Ohm across primary and secondary windings.

Thanks for your time and your willing to open my eyes

Why to split the terminated load to both windings?
I've also put R5 after C2. Is this correct or no matter?

ttl.jpg
 
Last edited:
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.