3 Application Interface
Copyright © Fibocom Wireless Inc.
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Figure 12. Reference circuit for N.C. SIM card slot
The principles of the N.C.SIM card slot are described as follows:
When the SIM card is detached, it connects the short circuit between CD and SW pins,
and drives the SIM1_DETECT pin low.
When the SIM card is inserted, it connects an open circuit between CD and SW pins,
and drives the SIM1_DETECT pin high.
3.4.2.2
N.O. SIM Card Slot
The reference circuit design for N.O. (Normally Open) SIM card slot is shown in Figure 13:
Figure 13. Reference circuit for N.O. SIM card slot
