MC7455 Dual SIM Switching

Hi All,

I’m new for using MC7455 module, and came up with some dumb questions, can some experts be able to clarify my confusions?

1: MC7455 Edge connector pin3, pin5, pin44 can be used for customer-defined external switch control for multiple antennas as the data-sheet mentioned, as far as we understand, we only have 3 antennas which one for main TX/RX, one for GPS and the third one for MIMO, so could you help to explain in this module, how exactly the antenna switching work? Because in my mind, we only have one TX/RX path, and there is no bands switching happen, or the antennas switching is something else?

2: MC7455 module supports Dual-SIMs, so does the module also support the nano-sim?

3: For Dual-SIMs, will it be possible to work at the same time but in different bands? If so, how the antennas will work? If not, what’s the purpose to have connections for 2 SIMs on the edge connector?

4: Module pin11 which is 1.8V voltage reference came from PMIC PMD9635 inside the module, what’s the purpose of this pin? Does this pin can be used for powering the 1.8V Vcc SIM card (which I think it will the nano SIM)?

Thank you very much!

  1. See my explanations here.

  2. SIM card’s form factor doesn’t matter.

  3. No. For every moment, only one card can be assigned as active. Two sets of lines are for convenience, to simplify system designer’s work: no additional hardware (external switch etc.) is required.
    Another usful feature: with this native, “internal” SIM selection you don’t need to reboot a modem (or enter/leave LPM) after SIM switching anymore.

  4. SIM’s nominal Vcc value doesn’t depend on its form factor. The only difference between full-sized, mini, micro, nano SIMs is size, dimentions.
    And…you don’t have to think about SIM powering at all. Simply connect its Vcc line to corresponding UIM_PWR pin, and everything will be sorted out by modem itself, without your attention.