Product Info

LTE Module Series
EC21 Hardware Design
EC21_Hardware_Design
3-21
/ 105
(U)SIM Interface
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
USIM_GND
10
Specified ground for
(U)SIM card
USIM_VDD
14
PO
Power supply for
(U)SIM card
For 1.8V (U)SIM:
Vmax=1.9V
Vmin=1.7V
For 3.0V (U)SIM:
Vmax=3.05V
Vmin=2.7V
I
O
max=50mA
Either 1.8V or 3.0V is
supported by the
module automatically.
USIM_DATA
15
IO
Data signal of
(U)SIM card
For 1.8V (U)SIM:
V
IL
max=0.6V
V
IH
min=1.2V
V
OL
max=0.45V
V
OH
min=1.35V
For 3.0V (U)SIM:
V
IL
max=1.0V
V
IH
min=1.95V
V
OL
max=0.45V
V
OH
min=2.55V
USIM_CLK
16
DO
Clock 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
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
USIM_
PRESENCE
13
DI
(U)SIM card
insertion detection
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.