LTE Standard Module Series
EC25 Hardware Design
EC25_Hardware_Design 27 / 130
For 3.0V (U)SIM:
V
OL
max=0.45V
V
OH
min=2.55V
USIM_RST 17
DO
Reset signal of
(U)SIM card
For 1.8V (U)SIM:
V
OL
max=0.45V
V
OH
min=1.35V
For 3.0V (U)SIM:
V
OL
max=0.45V
V
OH
min=2.55V
Main UART Interface
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
RI
62
DO
Ring indicator
V
OL
max=0.45V
V
OH
min=1.35V
1.8V power domain.
If unused, keep it
open.
DCD 63 DO
Data carrier
detection
V
OL
max=0.45V
V
OH
min=1.35V
1.8V power domain.
If unused, keep it
open.
CTS
64
DO Clear to send
V
OL
max=0.45V
V
OH
min=1.35V
1.8V power domain.
If unused, keep it
open.
RTS 65 DI
Request
to
send
V
IL
min=-0.3V
V
IL
max=0.6V
V
IH
min=1.2V
V
IH
max=2.0V
1.8V power domain.
If unused, keep it
open.
DTR 66 DI
Data terminal ready,
sleep mode control
V
IL
min=-0.3V
V
IL
max=0.6V
V
IH
min=1.2V
V
IH
max=2.0V
1.8V power domain.
Pulled up by default.
Low level wakes up
the module.
If unused, keep it
open.
TXD 67 DO
Transmit
data
V
OL
max=0.45V
V
OH
min=1.35V
1.8V power domain.
If unused, keep it
open.
RXD 68 DI
Receive
data
V
IL
min=-0.3V
V
IL
max=0.6V
V
IH
min=1.2V
V
IH
max=2.0V
1.8V power domain.
If unused, keep it
open.
Debug UART Interface
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment