Quectel EG25-G, Hardware Design

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LTE Module Series
EG25-G Hardware Design
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3.5.1.2. USB Application with USB Remote Wakeup Function
If the host supports USB suspension/resume and remote wakeup function, the following three
preconditions must be met to let the module enter into the sleep mode.
 Execute AT+QSCLK=1 command to enable sleep mode.
 Ensure the DTR is held at high level or keep it open.
 The host’s USB bus, which is connected with the module’s USB interface, enters into suspension
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
Figure 4: Sleep Mode Application with USB Remote Wakeup
 Sending data to EG25-G through USB will wake up the module.
 When EG25-G has a URC to report, the module will send remote wake-up signals via USB bus so as
to wake up the host.
3.5.1.3. USB Application with USB Suspension/Resume and RI Function
If the host supports USB suspension and resume, but does not support remote wake-up function, the RI
signal is needed to wake up the host.
There are three preconditions to let the module enter into the sleep mode.
 Execute AT+QSCLK=1 command to enable the sleep mode.
 Ensure the DTR is held at high level or keep it open.
 The host’s USB bus, which is connected with the module’s USB interface, enters into suspension
state.