SimCom SIM800C, Проектирование аппаратного обеспечения

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Smart Machine Smart Decision
SIM800C_Hardware_Design_V1.02
14
2015-4-27
VRTC 28 I/O Power supply for RTC
It is recommended to
connect with a battery or a
capacitor (e.g. 4.7uF).
VDD_EXT 40 O 2.8V power output
If these pins are unused,
keep open.
GND
8,13,19,21,27,30,
31,33,36,37
Ground
GND for VBAT recommend
to use 36,37pin
Power on/down
PWRKEY 39 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
MICP 9
MICN 10
I Differential audio input
SPKP 11
SPKN 12
O Differential audio output
If these pins are unused,
keep open.
GPIO
NETLIGHT 41 O Network status
STATUS 42 O Power on status
Serial port
UART1_DTR 6 I Data terminal ready
UART1_RI 7 O Ring indicator
UART1_DCD 5 O Data carrier detect
UART1_CTS 4 O Clear to send
UART1_RTS 3 I Request to send
UART1_TXD 1 O Transmit data
UART1_RXD 2 I Receive data
UART2_TXD 22 O Transmit data
UART2_RXD 23 I Receive data
If these pins are unused,
keep open.
Debug interface
USB_VBUS 24 I
USB_DP 25 I/O
USB_DN 26 I/O
Debug and download
If these pins are unused,
keep open.
ADC
ADC 38 I
10bit general analog to digital
converter If these pins are unused,
keep open.
SIM card interface
SIM_VDD 18 O
Voltage supply for SIM card.
Support 1.8V or 3V SIM card
SIM_DATA 15 I/O SIM data input/output
SIM_CLK 16 O SIM clock
SIM_RST 17 O SIM reset
All signals of SIM interface
should be protected against
ESD with a TVS diode
array.
SIM_DET 14 I SIM card detection If these pins are unused,