A20-OLINUXINO-MICRO_4GB_Rev_G1, Impedance Line and Trace Width Issue

[huxyz]

We are working on a project on which we are modifying A20-OLinuXino-MICRO-4GB board. We are in contact with a PCB manufacturer, and they want us to change our design to be able to satisfy the desired criteria.

We know that this version of Olinuxio has 60 Ohm Impedance Line. We have learned this value by asking here and confirmed it by calculating. We asked manufacturer to produce the board at that value but they stated that they cannot do by keeping the trace width at 5 mil. They want us to change it.

We didnt make any changes in Olinuxio design related to Impedance Lines. However, we are on the edge of changing it, but we are not that much interested in. That is why i wanna learn whether we can make it produce at 50 Ohm instead of 60 Ohm. I have no idea why Olimex prefered 60 to 50. Is 60 a "must" for that circuit?

My other question is related to the trace width. The manufacturer wants us to change it from 5 mil to 4.3 mil to meet the 60 Ohm requirement. If 60 is a "must", then we need to change the width. Is it ok to do it? Does it jeopardize the design if we modify the traces in that way?

[LubOlimex]

50 Ohm should be ok. 60 Ohm is not a must.

Best regards,
Lub/OLIMEX