CLM920_AC5 Mini PCIE LTE Module Hardware Manual
Shanghai Yuge Information Technology co., LTD
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The serial port level of the module is 1.8V. If the serial port needs to be connected to a 3.3V
level MCU, an external level conversion chip needs to be added to achieve level matching.
The chip connection method can refer to the following circuit
：
Figure 3-12 Level conversion circuit
3.7 USIM interface
The CLM920_AC5 Mini PCIE module provides a USIM card interface compatible with
the ISO 7816-3 standard. The power of the USIM card is provided by the internal power
regulator of the module and supports 1.8V / 3.0V.
Table 3-9 SIM card signal definition
Pin
Signal name
IO
High value
Description
6
UIM_DET
DI
1.8V
SIM card hot swap 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_AC5 Mini PCIE module does not have its own USIM card slot. Users need to
design a USIM card slot on their own interface board.
The reference design drawing of the USIM card interface is as follows
：
