Smart Machine Smart Decision
SIM800_Hardware Design_V1.10 15 2018-08-13
3.2. Pin Description
Table 4: Pin description
Pin name
number
I/O Description Comment
Power supply
VBAT 55,56,57 I
SIM800 supplies 3 VBAT pins, and
the power range is from 3.4V to 4.4V.
Power supply should provide
sufficient current so that the module
can work normally; the peak current
is nearly 2A.
Zener diode is Strongly
recommended to anti surge
on VBAT.
VRTC 26 I/O Power supply for RTC
It is recommended to
connect VRTC to a battery
or a capacitor (e.g. 4.7uF).
GND
2,17,18,29,3
9,45,46,54,5
8,59,61,62,6
3,64,65
Ground
GND for VBAT
recommend to use 62, 63,
64, 65 pin
.
Power on/off
PWRKEY 1 I
PWRKEY should be pulled low at
least 1.2 second and then r
power on/down the module.
VBAT.
Audio interface
MICP 19
I Differential audio input
Keep floating if unused.
MICN 20
SPKP 21
O Differential audio output
SPKN 22
PCM interface
PCM interface for audio Keep floating if unused.
PCM_CLK 68 I
Keypad interface
KBC4 47 I
Support up to 50 buttons (5*5*2)
Keep floating if unused.
(KBC0 can not be pulled
down).
KBC3 48 I
KBC1 50 I
KBR4 40 O