User's Manual

Table Of Contents
SIM7090G User Manual V1.01
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lines. Typically, the capacitance value should be less than 3pF.
Keep the ESD protection components as close to the USB connector as possible.
The USB interface is strongly recommended to reserve test points.
The USB_DM and USB_DP nets must be traced by 90Ohm+/-10% differential impedance.
3.5 SIM Interface
SIM7090G only supports 1.8V SIM Cards.
Table 15: SIM electronic characteristic in 1.8V mode (SIM_VDD=1.8V)
Symbol
Parameter
Min.
Typ.
Max.
Unit
SIM_VDD
LDO power output voltage
1.75
1.8
1.95
V
V
IH
High-level input voltage
0.65*SIM_VDD
-
SIM_VDD +0.3
V
V
IL
Low-level input voltage
-0.3
0
0.35*SIM_VDD
V
V
OH
High-level output voltage
SIM_VDD -0.45
-
SIM_VDD
V
V
OL
Low-level output voltage
0
0
0.45
V
The module does not support 3V SIM card.
The software does not support the SIM card hot swap function.
3.5.1. SIM Application Guide
It is recommended to use an ESD protection component such as ESDA6V1W5 produced by ST
(www.st.com ) or SMF15C produced by ON SEMI (www.onsemi.com ). Note that the SIM peripheral circuit
should be close to the SIM card socket. The following figure shows the 6-pin SIM card holder reference
circuit.
NOTE
NOTE