LTE Module Series
EC21 Hardware Design
EC21_Hardware_Design Confidential / Released 26 / 94
COEX_UART_
TX
138
DO
LTE/WLAN
coexistence signal
V
OL
max=0.45V
V
OH
min=1.35V
1.8V power domain.
If unused, keep it
open.
WLAN_SLP_
CLK
118
DO WLAN sleep clock
If unused, keep it
open.
BT_RTS*
37
DI
BT UART 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.
BT_TXD*
38
DO
BT UART transmit
data
V
OL
max=0.45V
V
OH
min=1.35V
1.8V power domain.
If unused, keep it
open.
BT_RXD*
39
DI
BT UART 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.
BT_CTS*
40
DO
BT UART clear to
send
V
OL
max=0.45V
V
OH
min=1.35V
1.8V power domain.
If unused, keep it
open.
BT_EN*
139
DO
BT function control
via FC20 module
V
OL
max=0.45V
V
OH
min=1.35V
1.8V power domain.
If unused, keep it
open.
RF Interface
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
ANT_DIV
35
AI
Diversity antenna
pad
50 ohm impedance
If unused, keep it
open.
ANT_MAIN
49
IO
Main antenna pad
50 ohm impedance
ANT_GNSS
47
AI
GNSS antenna pad
50 ohm impedance
If unused, keep it
open.
GPIO Pins
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
WAKEUP_IN
1
DI
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.
Cannot be pulled up
before startup.
Low level wakes up
the module.
If unused, keep it
open.
W_DISABLE# 4
DI
Airplane mode
V
IL
min=-0.3V
1.8V power domain.
Quectel
Confidential
