Shanghai SIMCom Wireless Solutions Limited 201802 User Manual
Smart Machine Smart Decision
SIM7600V-H_User Manual_V1.00
2018-02-24
29
Table 12: USIM Electronic characteristic 3.0V mode (
USIM_VDD
=2.95V)
Symbol
Parameter
Min.
Typ.
Max.
Unit
USIM_
VDD
LDO power output voltage
2.75
2.95
3.05
V
V
IH
High-level input voltage
0.65*USIM_VDD
-
USIM_VDD +0.3
V
V
IL
Low-level input voltage
-0.3
0
0.25*USIM_VDD
V
V
OH
High-level output voltage
USIM_VDD -0.45
-
USIM_VDD
V
V
OL
Low-level output voltage
0
0
0.45
V
3.5.1
USIM Application Guide
It is recommended to use an ESD protection component such as ESDA6V1W5 produced by ST
(
(
) or SMF15C produced by ON SEMI (
). Note that the USIM
peripheral circuit should be close to the USIM card socket.The following figure shows the 6-pin
SIM card holder reference circuit.
SIM card holder reference circuit.
Figure 18: USIM interface reference circuit
Note: USIM_DATA has been pulled up with a100KΩ resistor to USIM_VDD in module. A 100nF
capacitor on USIM_VDD is used to reduceinterference. For more details of AT commands about
USIM, please refer to document [1].
capacitor on USIM_VDD is used to reduceinterference. For more details of AT commands about
USIM, please refer to document [1].
3.5.2
SIM Card Design Guide
SIM card signal could be interferenced by some high frequency signal, it is strongly recommended
to follow these guidelines while designing:
to follow these guidelines while designing:
SIM card holder should be far away from antenna
SIM traces should keep away from RF lines, VBAT and high-speed signal lines
The traces should be as short as possible
Keep SIM card holder’s GND connect to main ground directly