User's Manual

LTE Module Series
EC25Hardware Design
EC25_Hardware_DesignConfidential / Released 31 / 90
 Sending data to EC25through USB will wake up the module.
 When EC25has URC to report, RI signal will wake up the host.
3.5.1.4. USB Application without USB Suspend Function
If the host does not support USB suspend function, you should disconnect USB_VBUS with additional
control circuit to let the module enter into sleep mode.
 Execute AT+QSCLK=1commandto enable the sleep mode.
 Ensure the DTR is held in high level or keep it open.
 Disconnect USB_VBUS.
The following figure shows the connection between the module and the host.
USB_VBUS
USB_DP
USB_DM
AP_READY
VDD
USB_DP
USB_DM
GPIO
Module Host
RI
EINT
Power
Switch
GPIO
GND
GND
Figure 6: Sleep Mode Application without Suspend Function
Switching on the power switch to supply power to USB_VBUS will wake up the module.
Please pay attention to the level match shown in dotted line between the module and the host.Refer to
document [1] for more details about EC25 power management application.
3.5.2. Airplane Mode
When the module enters into airplane mode, the RF function does not work, and all AT commands
correlative with RF function will be inaccessible. This mode can be set via the following ways.
NOTE