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LTE Standard Module Series
EC20 R2.1 Mini PCIe Hardware Design
EC20_R2.1_Mini_PCIe_Hardware_Design 16 / 51
(U)SIM card
9
GND
GND
Mini card ground
10
UIM_DATA
USIM_DATA
IO
Data signal of (U)SIM
card
11
REFCLK-
UART_RX
DI
UART receive data
Connect to
DTE’s TX.
12
UIM_CLK
USIM_CLK
DO
Clock signal of (U)SIM
card
13
UART_TX
DO
UART transmit data
Connect to
DTE’s RX.
14
UIM_RESET
USIM_RST
DO
Reset signal of (U)SIM
card
15
GND
GND
Mini card ground
16
UIM_VPP
RESERVED
Reserved
17
RESERVED
RI
DO
Ring indication
18
GND
GND
Mini card ground
19
RESERVED
RESERVED
Reserved
20
W_DISABLE#
W_DISABLE#
DI
Airplane mode control
Active low.
21
GND
GND
Mini card ground
22
PERST#
PERST#
DI
Fundamental reset
signal
Active low.
23
PERn0
UART_CTS
DI
UART clear to send
Connect to
DTE’s RTS.
24
3.3Vaux
RESERVED
Reserved
25
PERp0
UART_RTS
DO
UART request to send
Connect to
DTE’s CTS.
26
GND
GND
Mini card ground
27
GND
GND
Mini card ground
28
1.5V
NC
Not connected
29
GND
GND
Mini card ground
30
SMB_CLK
I2C_SCL
DO
I2C serial clock
Require
external
pull-up to 1.8V.