User Manual

GSM/GPRS Module Series
GC10 Hardware Design
GC10_Hardware_Design Confidential / Released 26 / 76
The turn-on timing is illustrated as the following figure:
VDD_EXT
(OUTPUT)
NETLIGHT
(OUTPUT)
V
IL
< 2.0V
V
IH
> 2.3V
VBAT
PWRKEY
(INPUT)
>1s
OFF
BOOTING
MODULE
STATUS
RUNNING
>10ms
>910ms
EMERG_OFF
(INPUT)
T
1
Figure 9: Turn-on Timing
1. Make sure that VBAT is stable before pulling down PWRKEY pin. At least 30ms for T
1
is
recommended.
2.
EMERG_OFF should be floated when it is unused.
You can monitor the status of the NETLIGHT pin to judge whether the module is power-on. After the
NETLIGHT pin goes to pulse, PWRKEY can be released. If the NETLIGHT 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 by the PWRKEY pin.
 Normal power down procedure: Turn off module by 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 by the EMERG_OFF pin.
NOTES