NB-IoT Module Series
BC66 Hardware Design
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3.10. USIM Interface
The module provides a USIM interface compliant to ISO/IEC 7816-3, enabling the module to access to
external USIM cards.
The external USIM card is powered by an internal regulator in the module and supports 1.8V power
supply.
Table 11: Pin Definition of USIM Interface
A reference circuit design for USIM interface with a 6-pin USIM card connector is illustrated below.
Module
SIM_VDD
SIM_GND
SIM_RST
SIM_CLK
SIM_DATA
22R
22R
22R
100nF
USIM Card Connector
GND
TVS
33pF33pF 33pF
VCC
RST
CLK
IO
VPP
GND
GND
33pF
10K
Figure 19: Reference Circuit for USIM Interface with a 6-pin USIM Card Connector
For more information of USIM card connector, please visit http://www.amphenol.com or
In order to enhance the reliability and availability of USIM card in application, please follow the criteria
below in USIM circuit design:
Pin Name
Pin No.
Description
Comment
SIM_VDD
14
Power supply for USIM card
Voltage accuracy: 1.8V±5%.
Maximum supply current: about 60mA.
SIM_CLK
13
Clock signal of USIM card
SIM_DATA
11
Data signal of USIM card
SIM_RST
12
Reset signal of USIM card
SIM_GND
10
Specified ground for USIM card