Service Guide
Table Of Contents
- Safety Information
- About the Document
- Contents
- Table Index
- Figure Index
- 1 Introduction
- 2 Product Overview
- 3 Operating Characteristics
- 4 Application Interfaces
- 5 Antenna Interfaces
- 6 Reliability, Radio, and Electrical Characteristics
- 7 Mechanical Information
- 8 Storage, Manufacturing, and Packaging
- 9 Appendix References
LTE Standard Module Series
EG915U_Series_Hardware_Design 37 / 90
3.6.1. Turn Off with PWPKEY
Drive the PWRKEY pin low for at least 3 s and then release PWRKEY. After this, the module executes
power-down procedure. The power-down scenario is illustrated in the following figure.
VBAT
PWRKEY
30 s
3 s
Running
Power-down procedure
OFF
Module
Status
Figure 13: Timing of Turning off the Module
3.6.2. Turn Off with AT Command
It is also a safe way to use AT+QPOWD to turn off the module, which is similar to turning off the module
via the PWRKEY pin.
Please refer to document [2] for details about AT+QPOWD command.
1. To avoid damaging internal flash, do not switch off the power supply when the module works
normally. Only after shutting down the module with PWRKEY or AT command can you cut off the
power supply.
2. When the PWRKEY pin has been kept pulled down directly to GND, the module will not boot
automatically after being turned off with the AT command. In this case, it is necessary to forcibly
disconnect the VBAT power supply and power on the module again. Therefore, we recommend to
use a control circuit to drive the PWEKEY high/low to turn on/off the module instead of keeping the
PWRKEY connected to GND.
3. When being turned off, the module will log out of the network. The time for logging out relates to its
network status. Thus, please pay attention to the shutdown time in your design because the actual
shutdown time varies according to the network status.
NOTE