using 100 ohm diff pair trace as 2 single ended signals

[violat]

Hi ,

can I use 100 ohm differential impedance traces as 2 unrelated single ended LVCMOS 3.3V signals ?

Thanks
Viola

 

[KlausST]

Hi,

It depends:
At least you have to expect a lot of crosstalk:
If you can filter this out ... but this reduces bandwidth.

I don´t recommend it.

Klaus

 

[violat]

Hi,

It depends:
At least you have to expect a lot of crosstalk:
If you can filter this out ... but this reduces bandwidth.

I don´t recommend it.

Klaus

Assuming low speed ~5 Mhz single ended digital signals - do you still see a problem?
and besides crosstalk - do you see other issues?

Thank you Klaus for your reply.

Viola

 

[KlausST]

Assuming low speed ~5 Mhz single ended digital signals - do you still see a problem?

in other words:
Two roads crossing.
To avoid an accident you need to slow down. --> and take care of the others (filter).
Just slowing down won´t prevent from an accident.

In case there is another car nearby you may accelerate or slow down to avoid contact.

Klaus

 

[FvM]

Crosstalk can affect the signal quality of the disturbed signal i n different ways. Obviously by changing the logic state if the receiver threshold is exceeded. But if the the disturbed signal has slow edges, even a small crosstalk level can shift the effective edge time and cause jitter.

There are several parameters determining the crosstalk effect. Ratio of even and odd line impedance, line length, source and load impedances, signal rise time.