Quectel LTE-A Series, Hardware Design

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LTE-A Module Series
EG18 Hardware Design
EG18_Hardware_Design 34 / 104

Sending data to EG18 through USB will wake up the module.

When EG18 has a URC to report, the module will send remote wake-up signals via USB bus to wake
up the host.
3.4.1.3. USB Application with USB Suspend/Resume and RI Function
If the host supports USB suspend/resume, but does not support remote wake-up function, RI signal is
needed to wake up the host.
There are three preconditions to make the module enter into sleep mode.

Keep DTR at high level (pulled up by default).

Execute AT+QSCLK=1 command to enable the sleep mode.
 The host’s USB bus, which is connected with the module’s USB interface, has entered into suspend
state.
The following figure shows the connection between the module and the host.
USB_VBUS
USB Interface
VDD
USB Interface
Module Host
GND GND
RI EINT
Figure 6: Sleep Mode Application with RI

Sending data to EG18 through USB will wake up the module.

When EG18 has a URC to report, RI signal will wake up the host.
3.4.1.4. USB Application without USB Suspend Function
If the host does not support USB suspend function, USB_VBUS should be disconnected with an external
control circuit to make the module enter into sleep mode.

Keep DTR at high level (pulled up by default).

Execute AT+QSCLK=1 command to enable the sleep mode.

Disconnect USB_VBUS.