VT-MOD-CELL-B48 Hardware User Manual
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5.
Interface Electrical Characteristics
5.1 Overview
This chapter mainly describes each interface application of VT-MOD-CELL-B48 LTE
module, including:
5.1.1
USIM card interface
5.1.2
Power interface
5.1.3
USB bus
5.1.4
LED status indication
5.1.5
RESET interface
5.2 USIM Card Interface
USIM is a smart card for UMTS/LTE cellular applications. The USIM provides the
required subscription information to allow the mobile equipment to attach to a UMTS
or LTE network. The USIM also provides the subscriber’s verification procedures as
well as authentication methods for network authentication during the attach
procedures.
A class B (3.0 V)/class C (1.8 V) USIM card can be connected to VT-MOD-CELL-
B48 module. The USIM card interface signals are shown in Table 4-1.
Table 4-1 USIM pins
PIN
Name
Description
Direction to Module
8
VSIM
Power source for the external
USIM
Output
10
UIM_DATA
External USIM data signal
Input/output
12
UIM_CLK
External USIM clock signal
Output
14
UIM_RESET
External USIM reset signal
Output
Note: It is recommended that the USIM card is inserted only after the power of the
module is disconnected, otherwise the USIM card can be destroyed.
