SimCom SIM800H, Hardware Design Manual

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Smart Machine Smart Decision
SIM800H_Hardware_Design_V1.01
16
2013-08-20
3.2. Pin Description
Table 4: Pin description
Pin name Pin number I/O Description Comment
Power supply
VBAT 1,42 I Power supply
VRTC 56 I/O Power supply for RTC
It is recommended to
connect with a battery or a
capacitor (e.g. 4.7uF).
VEXT 18 O 2.8V power output
If these pins are unused,
keep open.
GND
2,6,8,35,37,38,39,
41,43,44,45,58,67
,71,72,73,76,77,7
8,79,80,81,82,83,
84,85,86,87,88
Ground
GND for VBAT recommend
to use 2,43,44,45pin
Power on/down
PWRKEY 48 I
PWRKEY should be pulled low at
least 1 second and then released to
power on/down the module.
Internally pulled up to
VBAT.
Audio interfaces
MIC1P 52
MIC1N 12
I Differential audio input
SPK1P 53
SPK1N 13
O Differential audio output
MIC2P 9
MIC2N 10
I Differential audio input
SPK2P 51
SPK2N 11
O Differential audio output
If these pins are unused,
keep open.
PCM interface
PCMCLK 29 O
PCMOUT 30 O
PCMSYNC 65 O
PCMIN 66 I
PCM interface for audio
If these pins are unused,
keep open.
Keypads interface
COL4 24 I
COL3 21 I
COL2 22 I
COL1 25 I
COL0 20 I
ROW4 63 O
ROW3 23 O
Support up to 50 buttons (5*5*2) If these pins are unused,
keep open.
（
Pin number 20
external cannot be pulled
down
）