Users Manual Part 2

SIM8260A_Hardware Design_V1.05
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3.8 (U)SIM Interface
SIM8260A supports two (U)SIM cards but single standby. (U)SIM1 and (U)SIM2 are dual-voltage 1.8 V or
3.0 V interfaces.
Table 30: (U)SIM electronic characteristics in 1.8V mode ((U)SIM_PWR=1.8V)
Symbol
Parameter
Min.
Typ.
Max.
Unit
(U)SIM_VDD
Power supply for (U)SIM card
1.65
1.8
1.95
V
V
IH
High-level input voltage
1.26
-
1.95
V
V
IL
Low-level input voltage
0
-
0.36
V
V
OH
High-level output voltage
1.44
-
1.8
V
V
OL
Low-level output voltage
0
-
0.4
V
Table 31: (U)SIM electronic characteristics 3.0V mode ((U)SIM_PWR=3.0V)
Symbol
Parameter
Min.
Typ.
Max.
Unit
(U)SIM_VDD
Power supply for (U)SIM card
2.7
3.0
3.05
V
V
IH
High-level input voltage
2.1
-
3.05
V
V
IL
Low-level input voltage
0
-
0.6
V
V
OH
High-level output voltage
2.4
-
3.0
V
V
OL
Low-level output voltage
0
-
0.4
V
The module supports (U)SIM card hot-swap function through the (U)SIM_DET pin, which is a level trigger
pin and needs to be pulled up externally. The USIM_DET pin requires pull up externally. The following
figure shows (U)SIM card reference circuit.
Figure 29: (U)SIM interface reference circuit