Secondary Sim Pinout MC7455

IoT Modules MC/EM Series
1

Why is it that the pinout of the secondary sim interface on the MC7455 does not follow the standard? Am I misunderstanding something?

2

What standard?

Regards

Matt

3

This one:
PCI Express® Mini Card Electromechanical Specification Revision 2.1
members.pcisig.com/wg/PCI-SIG/d … load/10031

  • for the second SIM, the standard defines no pins, so Sierra had to deviate to provide the additional signals
  • Sierra just loves to repurpose signals defined by the standard and making the card unworkable in a standard compliant slot. Happened to us multiple times we had to redesign a board because the module would not work at all or we were risking hardware damage - 1.8V reference on PCIe clock line, really?