Specifications

SIM7912&SIM7906 Hardware Design V1.02
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1. In order to avoid damaging internal flash, please do not switch off the power supply when the
module works normally. Only after the module is shut down by PWRKEY or AT command, the power
supply can be cut off.
2. When turning off module with AT command, please keep PWRKEY at high level after the execution
of power-off command. Otherwise, the module will be turned on again after successful turn-off.
3.3 Reset Function
Module can be reset by driving the RESET_N pin down to a low level for 500ms at least and then releasing
it.
The RESET_N signal has been internally pulled up to 1.8V, so there is no need to pull it up externally.
Please refer to the
following figure for the recommended reference circuit.
Reset Impulse
RESET_N
Reset
Logic
R
1.8V
Module
1K
200~600ms
GPIO
MCU
Figure 12: Reset the module use GPIO drive
Reset
Logic
R
1.8V
Module
1K
T
reset
200~600ms
RESET_N
Figure 13: Reset the module use button
Table 12: Definition of RESET_N pin