User's Manual
LE920 Hardware User Guide
1vv0301026 Rev.8 2015-01-03
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15.3. SIM interface
This section deals with the recommended schematics for the design of SIM interfaces on the
application boards.
15.3.1. 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 with 3GPP specification for USIM electrical testing.
LE920 contains an internal pull-up resistor of 20KΩ on SIMIO.
However, the un-mounted option in the 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 LE920 product:
Product P/N
C1 range (nF)
LE920-EU/NA
100 nF
Refer to the following document for the detail:
80000NT10026A - SIM Interface And ESD Protection Application Note Rev.2