Product Info

LTE Module Series
EC21 Hardware Design
EC21_Hardware_Design
3-19
/ 105
3.2. Pin Description
The following tables show the pin definition of EC21 module.
Table 3: I/O Parameters Definition
Type
Description
IO
Bidirectional
DI
Digital input
DO
Digital output
PI
Power input
PO
Power output
AI
Analog input
AO
Analog output
OD
Open drain
Table 4: Pin Description
Power Supply
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
VBAT_BB
59, 60
PI
Power supply for
module’s baseband
part
Vmax=4.3V
Vmin=3.3V
Vnorm=3.8V
It must be able to
provide sufficient current
up to 0.8A.
VBAT_RF
57, 58
PI
Power supply for
module’s RF part
Vmax=4.3V
Vmin=3.3V
Vnorm=3.8V
It must be able to
provide sufficient current
up to 1.8A in a burst
transmission.
VDD_EXT
7
PO
Provide 1.8V for
external circuit
Vnorm=1.8V
I
O
max=50mA
Power supply for
external GPIO’s pull-up
circuits.
If unused, keep it open.
GND
8, 9, 19,
22, 36, 46,
Ground