Quectel EG25-G - Table 9: Pin Definition of (U)Sim Interface

LTE Module Series
EG25-G Hardware Design
EG25-G_Hardware_Design 41 / 100
Table 9: Pin Definition of (U)SIM Interface
Pin Name
Pin No.
I/O
Description
Comment
USIM_VDD
14
PO
Power supply for (U)SIM card
Either 1.8V or 3.0V is supported
by the module automatically.
USIM_DATA
15
IO
Data signal of (U)SIM card
USIM_CLK
16
DO
Clock signal of (U)SIM card
USIM_RST
17
DO
Reset signal of (U)SIM card
USIM_
PRESENCE
13
DI
(U)SIM card insertion detection
1.8V power domain.
If unused, keep it open.
USIM_GND
10
Specified ground for (U)SIM
card
EG25-G supports (U)SIM card hot-plug via the USIM_PRESENCE pin. The function supports low level
and high level detections, and is disabled by default. Please refer to document [2] for more details about
AT+QSIMDET command.
The following figure shows a reference design for (U)SIM interface with an 8-pin (U)SIM card connector.
Module
USIM_VDD
USIM_GND
USIM_RST
USIM_CLK
USIM_DATA
USIM_PRESENCE
0R
0R
0R
VDD_EXT
51K
100nF
GND
GND
33pF
33pF 33pF
VCC
RST
CLK
IO
VPP
GND
GND
USIM_VDD
15K
(U)SIM Card Connector
Figure 17: Reference Circuit of (U)SIM Interface with an 8-Pin (U)SIM Card Connector
If (U)SIM card detection function is not needed, please keep USIM_PRESENCE unconnected. A
reference circuit for (U)SIM interface with a 6-pin (U)SIM card connector is illustrated in the following
figure.