SimCom SIM808, Проектирование аппаратного обеспечения

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SIM808_Hardware Design_V1.00 2014.03.27 16
3.2 Pin Description
Table 5: Pin description
Pin name Pin number I/O Description Comment
Power supply
VBAT 4,5,6 I
SIM808 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 17 I/O Power supply for RTC
It is recommended to
connect VRTC to a
battery or a capacitor
(e.g. 4.7uF).
VDD_EXT 7 O 2.8V power output
Keep floating if
unused.
GND
1,2,3,18,28,34
,36,40,51,52,5
4,64,65,67,68
Ground
Recommend
connecting 1,2,3pin
to the power GND.
Power on/off
PWRKEY 8 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 interface
MIC1P 19
MIC1N 20
I Differential audio input
SPK1P 21
SPK1N 22
O Differential audio output
Keep floating if
unused.
PCM interface
PCM_OUT 48 O
PCM_IN 47 I
PCM_SYNC 45 O
PCM_CLK 46 I
PCM interface for audio
Keep floating if
unused.
Keypad interface
COL3 59 I
COL2 60 I
COL1 61 I
COL0 62 I
ROW3 55 O
ROW2 56 O
ROW1 57 O
ROW0 58 O
Support up to 32 buttons (4*4*2)
Keep floating if
unused. (COL0 can
not be pulled down).