User's Manual

GSM/GPRS Module Series
M35 User Manual
M35_User_Manual Confidential / Released 19 / 85
3.1.2. Pin Description
Table 3: Pin Description
Power Supply
PIN NAME
PIN NO.
I/O
DESCRIPTION
DC
CHARACTERISTICS
COMMENT
VBAT
33, 34
I
Main power supply of
module:
VBAT=3.3V~4.6V
Vmax=4.6V
Vmin=3.3V
Vnorm=4.0V
Make sure that
supply sufficient
current in a
transmitting burst
typically rises to
1.6A.
VRTC
32
I/O
Power supply for RTC
when VBAT is not supplied
for the system.
Charging for backup
battery or golden capacitor
when the VBAT is applied.
VImax=3.3V
VImin=1.5V
VInorm=2.8V
VOmax=3V
VOmin=2V
VOnorm=2.8V
Iout(max)=2mA
Iin≈10uA
If unused, keep
this pin open.
VDD_
EXT
19
O
Supply 2.8V voltage for
external circuit.
Vmax=2.9V
Vmin=2.7V
Vnorm=2.8V
Imax=20mA
1. If unused, keep
this pin open.
2. Recommend to
add a 2.2~4.7uF
bypass capacitor,
when using this
pin for power
supply.
GND
35,36,3
7,38, 40
Ground
Turn on/off
PIN NAME
PIN NO.
I/O
DESCRIPTION
DC
CHARACTERISTICS
COMMENT
PWRKEY
10
I
Power on/off key.
PWRKEY should be pulled
down for a moment to turn
on or turn off the system.
VILmax=
0.1×VBAT
VIHmin=
0.6×VBAT
VImax=3.1V
Emergency Shutdown