Telit Wireless Solutions GE310-GNSS, Руководство по конструкции

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SIM Integration Design Guide
80000NT10001A Rev. 15 Page 14 of 32 2021-01-29
Not Subject to NDA
SIM-ON-CHIP
In the M2M applications, there are several cases where the SIM Card will never be changed
once installed, also it would be preferable if it shouldn’t be possible to remove it at all;
furthermore the SIM Card is required to work in a more harsh environment with respect to
standard mobile phones SIM Cards. In order to address these kinds of application the SIM On
Chip have been developed; they are basically a special SIM Card chip packaged as a surface
mount assembly device that is then assembled together with the modem at the factory and
will be never removed from the application.
This approach results in a great advantage in terms of long term reliability because the
contacting issues that can arise due to moisture, vibrations and harsh environmental
conditions with standard SIM holders are avoided by design since the SIM On Chip is soldered
on the application PCB.
The Telit modules support the usage of M2M SIM-On-Chip and their usage is exactly the same
as for conventional SIM Cards.
SIM On Chip are interfaced with the same lines as for standard SIM:
• SIMVCC
•
SIMIO
• SIMRST
• SIMCLK
and shall be connected and decoupled in the same way as the standard SIM Card holder as
shown in the chapter 3.1. An example of SIM On Chip connection is shown in the following
schematic:
Figure 6-1 SIM On Chip connection
Since the SIM On Chip are not removable, it is possible to tie SIMIN to GND and eventually use
the AT command AT#SIMDET to simulate insertion/removal.