User's Manual

LTE Module Series
EC25-V User Manual
EC25-V_User_Manual Confidential / Released 24 /
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state.
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
GND
GND
RI
EINT
Figure 5: Sleep Application with RI
 Sending data to EC25 through USB will wake up the module.
 When EC25 has URC to report, RI signal will wake up the host.
3.5.1.4. USB Application without USB Suspend Function
If 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 command AT+QSCLK=1 to 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 Application without Suspend Function