L831-EA Module Hardware User Manual
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off it, pull down the FUL_CARD_POWER_OFF# or floating. For details as listed below:
Off modes
Methods
Condition
Software
Send AT+CPWROFF commands.
Normal power_off
Hardware
Pull down the FUL_CARD_POWER_OFF#
or floating.
Only used for system halted or happens
exceptions and the software modes can
not be used.
The description of hardware power_off as follows ( Pull down the FUL_CARD_POWER_OFF# or
floating ):
While pulling down the FUL_CARD_POWER_OFF# signals or floating, the modules` PMU (Power
Management Unit) will be reset, then the module will get into off modes from working modes.
Note
①
: the RESET_N signal must be pulled down before pulling down the FUL_CARD_POWER_OFF#
signal, and then the module will be turned off safely.
The Pulse Timing requirements as listed below:
Parameters
Condition
Minimum
Typical
Maximum
Unit
Pulse Width
Power off
5
100
ms
The Figure 5- 2 shows the power off timing control:
Figure5- 2 Power off Timing Control
5.2.1.3 Recommended Circuit Design of Power on/off signals
The recommended design of FUL_CARD_POWER_OFF# signal as follows:
