Smart Machine Smart Decision
SIM868_Series_Hardware_Design_V1.06
17
2017-07-13
3.2.
Pin Description
Table 6: Pin description
Pin name
Pin number
I/O Description
Comment
Power supply
GPS_VBAT
34
I
Power supply for GNSS
2.9V ~4.4V
GSM_VBAT
35
I
Power supply for GSM
3.4V ~4.4V
VDD_EXT
40
O
2.8V power output
If it is unused, keep open.
GND
8,13,19,21,27,30,
31,33,36,37,45,63,
66,67,69,70,71,72,
73,74,75,76,77
Ground
36
、
37 pins recommend for
GSM_VBAT.
Power on/off
PWRKEY
39
I
PWRKEY should be pulled low
and then released to power on/off
the module.
Internally pulled up to 3V
Audio interface
MICP
9
I
Differential audio input
If these pins are unused,
keep open.
MICN
10
SPK1P
11
O
Differential audio output
SPK1N
12
SPK2P
44
SPK2N
43
GNSS interface
GPS_RXD
62
I
Receive data
If these pins are unused,
keep open.
GPS_TXD
61
O
Transmit data
1PPS
60
O
Time Mark outputs timing pulse
GNSS_EN
59
I
GNSS power enable
VRTC
28
I/O Power supply for GNSS RTC
It is recommended to
connect with a battery.
SD interface
MCCA3
46
I/O
SD serial data I/O
If these pins are unused,
keep open.
MCCA2
47
I/O
MCCA1
48
I/O
MCCA0
49
I/O
MCCK
50
I/O SD serial clock
MCCM0
51
I/O SD command output
GPIO
NETLIGHT
41
O
Network status
If these pins are unused,
keep open.
STATUS
42
O
Power on status
GPIO1
57
I/O Programmable general purpose
input and output.
GPIO2
58
I/O
SIMCOM
CONFIDENTIAL
FILE
