HE920 Hardware User Guide
1vv0301014 Rev.9 – 2014-01-23
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Page 74 of 84
14.3.
SIM interface
This section deals with the recommended schematics for the design of SIM interfaces on the
application boards.
14.3.1.
SIM schematic example
Figure 1 illustrates in particular how the application side should be designed, and what values
the components should have.
NOTE FOR R1:
The resistor value on SIMIO pulled up to SIMVCC should be defined accordingly in order to
be compliant to 3GPP specification.
For HE920-EU and HE920-NA contain an internal pull-up resistor on SIMIO.
However, the un-mounted option in application design can be recommended in order to tune
R1 if necessary.
The following Table lists the values of C1 to be adopted with the HE920 product:
Product P/N
C1 range (nF)
HE920-EU
100 nF
HE920-NA
Refer to the following document for the detail;
Telit_SIM_Integration_Design_Guide_Application_Note
