SimCard signal connection with cable from one pcb to other

[htekin42]

Hi everybody,

We are making a new PCB design for one of my project and we are using a ready case and we need to make design according to that. We are using MiniPCI modems with USB interface which is connected to SBC. In our new design, we cannot put simcard connector pcb because user cannot reach to Simcard because of case. so we are planning to make another PCB with simcard connector and make connection with cables. Does it make any problem? I know sim card signals are very sensitive.
Here is the sample block diagram of explanation.

 

[marce]

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[FvM]

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Easier said than done. SIM interface involves bidirectional IO signal and different supply voltages.

Biggest problem is possible EMI when antenna is near modem respectively SIM. Use suffcient ground connections, e.g. flat cable with GND-signal1-GND-signal2-GND ... wire assigment. As short as possible.

 

[marce]

It's a more expensive solution, as it involves a bi-directional level device...
FCC/FPC cable types are a good choice, can either have a flexi PCB made with connector on main board (best) or have connectors on both boards, with FCC, lower cost than flexi PCB.