Jump to content
Superdad

EtherREGEN: Early general details [We are late but getting closer! ;-)]

Rate this topic

Recommended Posts

On 5/9/2019 at 6:16 AM, Superdad said:

 

Thanks.  And I forgot to mention that EtherREGEN is going to be on a 6-layer circuit board instead of a 4-layer. John is choosing to do it that way both for performance reasons and because he feels it will actually be easier to route everything. 

All this stuff is WAY above my pay/brain grade so I of course go along with whatever John says is best. B|

Easier to control the impedance of the routes with 6 layers, there does seem to be a preference for running high speed LVDS as microstrip on the outer layers, having half the signal in air as a dielectric and slightly faster propagation does help. It's interesting to see as digital signals get faster, layout is using more and more techniques from high speed analogue rf/microwave. It wont be long before we have speeds where signals will have to be routed as co-planer wave guides or as pseudo co-axial structures, doable on a PCB with high density interconnect designs but expensive. Looking forward to seeing pictures of the boards, always interested in looking at boards! I do it every day. Like yours they show a bit of OCD in the symmetry, years of doing IC's or PCB's does that to you.😁

This is also the fun level of Ethernet, the physical level.

Agree on shields could add more problems, than it fixes. Interesting to think about cables, quite simple to produce, plug into an RJ45...the complexity from the connector to the Phy on a PCB is way more interesting, and almost invisible to most people. A look at some of the info out there such as "en562767.pdf" will illustrate the task ahead for John.

Have fun.

Share this post


Link to post
Share on other sites
6 hours ago, Superdad said:

 

Sorry, but until EtherREGEN is done and shipping, we will not have time to experiment with Ethernet cables. :D

 

We expect that the only cable that will matter will be the one coming out of the 'B' side lone port and going into the DAC-connected renderer.  The whole point of the EtherREGEN's sophisticated isolated, dual-clock domain design is to make most upstream variables not matter.

 

All that said, in general we prefer that Ethernet cables not have their shields tied at both ends.  Even though all Ethernet ports have transformers (of varying levels--see my post elsewhere about those), I just don't see much good coming from connecting grounds between Ethernet devices via shield connections. 

 

Thanks for the clarification. Very helpful.

My setup will be unshielded CAT6:  Cheap and easy to cut to size.


[ AERIS G2 ] => [ MC3+USB x 3 <- -REF10 ] => [ Genelec 8341 x 2 + 7360 x 2 ]

[ Switchable to  [ Genelec 8331 x 2 + 7350 ]

Share this post


Link to post
Share on other sites
On 5/14/2019 at 6:51 PM, Superdad said:

 

Sorry, but until EtherREGEN is done and shipping, we will not have time to experiment with Ethernet cables. :D

 

We expect that the only cable that will matter will be the one coming out of the 'B' side lone port and going into the DAC-connected renderer.  The whole point of the EtherREGEN's sophisticated isolated, dual-clock domain design is to make most upstream variables not matter.

 

All that said, in general we prefer that Ethernet cables not have their shields tied at both ends.  Even though all Ethernet ports have transformers (of varying levels--see my post elsewhere about those), I just don't see much good coming from connecting grounds between Ethernet devices via shield connections. 

I’m using 3 Jitterbugs upstream (router, NAS, iMac). Can I sell them?

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×
×
  • Create New...