User's Manual

VT-MOD-CELL-B48 Hardware User Manual

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

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.