LTE Module Series
EG21-G Hardware Design
EG21-G_Hardware_Design 21 / 100
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.
Pull-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
DBG_TXD
12
DO Transmit data
V
OL
max=0.45V
V
OH
min=1.35V
1.8V power domain.
If unused, keep it
open.
DBG_RXD
11
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.
ADC Interfaces
Pin Name
Pin No.
I/O Description
DC Characteristics Comment
ADC0
45
AI
General purpose
Voltage range:
If unused, keep it