MeiG
Product
Manual
of
SLM750
Module
SLM750
Module
Hardware
Design
Page 20, total 84 pages
V
OH
min=2.55V
USIM_RST
17
DO
USIM card reset
line
1.8V USIM:
V
OL
max=0.45V
V
OH
min=1.35V
3.0V USIM:
V
OL
max=0.45V
V
OH
min=2.55V
-
USIM_PRESE
NCE
13 DI USIM
card
detection
V
IL
min=-0.3V
V
IL
max=0.6V
V
IH
min=1.2V
V
IH
max=2.0V
1.8Vpower
domain, require
external pull-up to
1.8V
USIM_VDD 14 PO USIM
card
supply voltage
1.8V USIM:
Vmax=1.9V
Vmin=1.7V
3.0V USIM:
Vmax=3.05V
Vmin=2.7V
I
o
max=50mA
Either 1.8V or
3.0V USIM card is
identified by the
module
automatically
USIM_GND 10 USIM
card
ground
Connect with
module ground
Main serial port
Pin name
Pin
number
I/O
Description
DC features
Note
RI 62
DO
Ring
indicator
VOLmax=0.45V
VOHmin=1.35V
1.8V power
domain.
If unused, keep
it open.
DCD 63
DO
Carrier
detect
VOLmax=0.45V
VOHmin=1.35V
1.8V power
domain.
If unused, keep
it open.
DTR
66
DI
DTE ready, sleep
mode control
VILmin=-0.3V
VILmax=0.6V
VIHmin=1.2V
VIHmax=2.0V
1.8V power
domain.
If unused, keep
it open.
RXD 68
DI
Receive
data
VILmin=-0.3V
VILmax=0.6V
VIHmin=1.2V
VIHmax=2.0V
1.8V power
domain.
If unused, keep
it open.
TXD 67
DO
Transmit
data
VOLmax=0.45V
VOHmin=1.35V
1.8V power
domain.
If unused, keep
it open.
CTS 64
DI
Clear
to
send VOLmax=0.45V
1.8V
power
