User's Manual
Table Of Contents
- Contents
- Table Index
- Figure Index
- 0. Revision history
- 1. Introduction
- 2. Product concept
- 3. Application interface
- 3.1. Pin
- 3.2. Operating modes
- 3.3. Power supply
- 3.4. Power on and down scenarios
- 3.5. Charging interface
- 3.6. Power saving
- 3.7. Summary of state transitions
- 3.8. RTC backup
- 3.9. Serial interfaces
- 3.10. Audio interfaces
- 3.11. SIM card interface
- 3.12. SD card interface
- 3.13. PCM interface
- 3.14. ADC
- 3.15. Behaviors of the RI
- 3.16. Network status indication
- 3.17. Operating status indication
- 4. Antenna interface
- 5. Electrical, reliability and radio characteristics
- 6. Mechanical dimensions
- 7. Storage and manufacturing
- Appendix A: GPRS coding schemes
- Appendix B: GPRS multi-slot classes
M80 Hardware Design
M80_HD_V1.2 - 35 -
EMERG_OFF
(INPUT)
VDD_EXT
(OUTPUT)
V
IL
<0.1*VBAT
V
IH
> 0.6*VBAT
VBAT
PWRKEY
(INPUT)
54ms
STATUS
(OUTPUT)
800ms
>1s
OFF
BOOTING
MODULE
STATUS
RUNNING
2
1
Figure 8: Timing of turning on system
① Make sure that VBAT is stable before pulling down PWRKEY pin. The time between them
is recommended 30ms.
② EMERG_OFF should be floated when it is unused
Note: Customer can monitor the voltage level of the STATUS pin to judge whether the module
is power-on. After the STATUS pin goes to high level, PWRKEY may be released. If the
STATUS pin is ignored, pull the PWRKEY pin to low level for more than 1 second 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