CLM920_NC3_LTE Module Hardware User Guide
Shang Hai YUGE Information Technology co., LTD
Page 20 of 37
The serial port level of the module is 1.8V. If the serial port needs to be connected to the MCU of
3.3V level, it is necessary to add a level conversion chip externally to achieve level matching. For the chip
connection method, refer to the following circuit:
Figure 3-12 Level shifting circuit
3.7 USIM Interface
The CLM920_NC5 Mini PCIE module provides an ISO 7816-3 compliant USIM card interface. The
USIM card power supply is provided by the module's internal power regulator and supports 1.8V/3.0V.
Table 3-9 SIM card signal definition
Pin number
Signal name
IO
High value
Description
6
UIM_DET
DI
1.8V
SIM card hot plug detection
8
UIM_PWR
PO
1.8V/2.85V
SIM card power supply
10
UIM_DATA
IO
1.8V/2.85V
SIM card data signal
12
UIM_CLK
DO
1.8V/2.85V
SIM card clock signal
14
UIM_RESET
DO
1.8V/2.85V
SIM card reset signal
3.7.1 USIM Card Reference Circuit
The CLM920_NC5 Mini PCIE module does not come with a USIM card slot. Users need to design a
USIM card slot on their own interface board.
The USIM card interface reference design is as follows: