SIM802 Hardware Design
After this moment, the AT commands can’t be executed. The module logs off from network and
enters POWER DOWN mode, and only the RTC is still active. POWER DOWN can also be
indicated by STATUS Pin, which is a low level voltage in this mode.
To monitor the temperature, you can use the “AT+CMTE” command to read the temperature
when the module is power on.
For details please refer to document [1]
You can restart SIM802 by driving the PWRKEY to a low level voltage for a period time, the
same as turning on SIM802 using the PWRKEY Pin. Before restarting the SIM802, you need
delay at least 500ms from detecting the STATUS low level on. The restarting scenarios illustrates
as the following figure.
STATUS
（
OUTPUT
）
Hiz
PWRKEY
（
INPUT
）
V
IL
<870mv
Restart > 500ms
Startup
Turn off
Figure 10: Timing of restart system
3.5 Charging interface
SIM802 has integrated a charging circuit inside the module for Li-Ion batteries charging control,
which make it very convenient for applications to manage their battery charging. A common
connection is shown in the following figure:
SIM802_HD_V2.01
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