Shanghai SIMCom Wireless Solutions Limited SIM7000G ユーザーズマニュアル
Smart Machine Smart Decision
SIM7000 _Hardware Design _V1.00
2017-05-23
The following figure shows the linear regulator reference circuit with 5V input and 3.8V output.
Figure 7: Linear regulator reference circuit
If there is a big voltage difference between input and output for VBAT power supply, or the
efficiency is extremely important, then a switching mode power supply will be preferable. The
following figure shows the switching mode power supply reference circuit.
efficiency is extremely important, then a switching mode power supply will be preferable. The
following figure shows the switching mode power supply reference circuit.
Figure 8: Switching mode power supply reference circuit
Note: The Switching Mode power supply solution for VBAT must be chosen carefully against
Electro Magnetic Interference and ripple current from depraving RF performance.
Electro Magnetic Interference and ripple current from depraving RF performance.
3.1.3
Voltage Monitor
To monitor the VBAT voltage, the AT command “AT+CBC” can be used.
To monitor whether the VBAT voltage is inside a special range, the AT command
“AT+CBATCHK” can be used to enable the overvoltage warning function and the under-voltage
warning function. The default value of the overvoltage warning function in the software is 4.3V,
and the default value of the under-voltage warning function is 3.1V.
“AT+CBATCHK” can be used to enable the overvoltage warning function and the under-voltage
warning function. The default value of the overvoltage warning function in the software is 4.3V,
and the default value of the under-voltage warning function is 3.1V.
When the VBAT voltage is out of the range, the module will be power off. If users need to power
off SIM7000 when the VBAT voltage is out of the range, the AT command “AT+CBATCHK” can
be used to enable the overvoltage power-off function and the under-voltage power-off function. The
default value of the overvoltage power-off function in the software is 4.4V, and the default value of
the under-voltage power-off function is 2.9V.
Note: Under-voltage warning function and under-voltage power-off function are disabled by
default. For more information about these AT commands, please refer to Document [1].
off SIM7000 when the VBAT voltage is out of the range, the AT command “AT+CBATCHK” can
be used to enable the overvoltage power-off function and the under-voltage power-off function. The
default value of the overvoltage power-off function in the software is 4.4V, and the default value of
the under-voltage power-off function is 2.9V.
Note: Under-voltage warning function and under-voltage power-off function are disabled by
default. For more information about these AT commands, please refer to Document [1].