User's Manual

Smart Machine Smart Decision
SIM868_Hardware_Design_V1.00 14 2016-06-20
power consumption is related with network settings (e.g. power control
level); uplink/downlink data rates and GPRS configuration (e.g. used
multi-slot settings).
Power off
Normal power off by sending AT command “AT+CPOWD=1” or using the PWRKEY. The
power management unit shuts down the power supply for the baseband part of the module.
Software is not active. The serial port is not accessible. Power supply (connected to 3V)
remains applied.
Minimum
functionality
mode
AT command “AT+CFUN” can be used to set the module to a minimum functionality mode
without removing the power supply. In this mode, the RF part of the module will not work
or the SIM card will not be accessible, or both RF part and SIM card will be closed, and the
serial port is still accessible. The power consumption in this mode is lower than normal
mode.
2.4. Functional Diagram
The following figure shows a functional diagram of SIM868:
 GSM baseband
 PMU
 The GSM Radio Frequency part
 Antenna interface
 GNSS interface
 Other interface
Figure 1: SIM868 functional diagram