I am a bit new in designing circuits. I am trying to make an interface to shutdown all the signals coming from an Ethernet cable. The design would look something like this:

enter image description here Can this be done using mosfets? if so, would it cause packet drop? Any suggestions on how i could do this?

Thank you for your time :)

  • 1
    \$\begingroup\$ Easiest will be a bus switch. ti.com/lit/ml/scdb006a/scdb006a.pdf \$\endgroup\$
    – mkeith
    May 21 '18 at 23:25
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    \$\begingroup\$ It will be challenging to implement it without adverse effect on the signals, especially for Gigabit ethernet. Especially if it is in the middle of the cable. Putting it on the same PCB close to the PHY would be much better. \$\endgroup\$
    – mkeith
    May 21 '18 at 23:26
  • \$\begingroup\$ @mkeith Except Ethernet isn't a bus… \$\endgroup\$
    – user39382
    May 21 '18 at 23:40
  • \$\begingroup\$ what about the signals that are being generated by any device on the right side of your diagram? \$\endgroup\$
    – jsotola
    May 21 '18 at 23:42
  • \$\begingroup\$ @duskwuff, you are just quibbling over terminology. They make switches that work with ethernet. The first time I used one was in 2000 on a single board computer with Gigabit Ethernet that could be routed to either of two jacks under BIOS control. \$\endgroup\$
    – mkeith
    May 22 '18 at 3:03

What is the purpose of this shutdown circuit? Safety in case of a electrical storm or just cutting off communications? Quality Relays meant for small signals (gold plated contacts), would be the least problematic electrically and provide pretty good electrical isolation.

  • \$\begingroup\$ hey sara, so in this case, i would need to use 8 relays right? (relay for each signal) \$\endgroup\$ May 22 '18 at 4:03
  • \$\begingroup\$ Yes, you would. But it is the method least likely to cause any problems with data getting corrupted, one big reason, is that there would be zero power supply noise to contaminate the signal. It is the way I would go because of those reasons, and it is simple and reliable. Go with sealed relays, so the gold plated contacts could not be contaminated in any way by the atmosphere. These kind of signal relays would not draw much power either. It is the way I would go if I was building something that does what you need. \$\endgroup\$
    – Sara Heart
    May 22 '18 at 6:06

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