Power Down - Quectel M12 Hardware Design

M12 Hardware Design
VBAT
2
EMERG_OFF
(INPUT)
PWRKEY
(INPUT)
VDD_EXT
(OUTPUT)
STATUS
(OUTPUT)
MODULE
STATUS
①
Make sure that VBAT voltage is stable before pulling down PWRKEY pin. The interval time
between them is recommended 30ms.
②
Keep the EMERG_OFF pin open if not used.
Note: Customer can monitor the voltage level of the STATUS pin to judge whether the module
is turned on. After the STATUS pin goes to high level, PWRKEY could be released. If the
STATUS pin is ignored, pull the PWRKEY pin to low level for more than 2 seconds to turn on
the module.

3.4.2. Power down

The following procedures can be used to turn off the module:

Normal power down procedure: Turn off module using the PWRKEY pin.
 Normal power down procedure: Turn off module using command "AT+QPOWD".

Over-voltage or under-voltage automatic shutdown: Take effect when over-voltage or
under-voltage is detected.

Emergent power down procedure: Turn off module using the EMERG_OFF pin.
M12_Hardware_Design_V3.3
1
54ms
OFF
Figure 8: Timing of turning on system
>1s
V <0.1*VBAT
IL
800ms
BOOTING
V > 0.6*VBAT
IH
RUNNING
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