Quectel EG91 Series Hardware Design page 44

Figure 17: Reference Circuit of (U)SIM Interface with an 8-pin (U)SIM Card Connector
If (U)SIM card detection function is not needed, please keep USIM_PRESENCE unconnected. A
reference circuit of (U)SIM interface with a 6-pin (U)SIM card connector is illustrated in the following
figure.
Figure 18: Reference Circuit of (U)SIM Interface with a 6-pin (U)SIM Card Connector
In order to enhance the reliability and availability of the (U)SIM cards in customers' applications, please
follow the criteria below in the (U)SIM circuit design:
 Keep placement of (U)SIM card connector to the module as close as possible. Keep the trace length
as less than 200mm as possible.
 Keep (U)SIM card signals away from RF and VBAT traces.
EG91_Series_Hardware_Design
LTE Standard Module Series
EG91 Series Hardware Design
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