Quectel EG91 Series Hardware Design page 34

Driving the host DTR to low level will wake up the module.
 When EG91 series module has a URC to report, RI signal will wake up the host. See Chapter 3.17
for details about RI behavior.
 AP_READY will detect the sleep state of host (can be configured to high level or low level detection).
See AT+QCFG="apready" for details.
3.5.1.2. USB Application with USB Remote Wakeup Function
If the host supports USB suspend/resume and remote wakeup functions, the following three preconditions
must be met to let the module enter sleep mode.
Execute AT+QSCLK=1 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 suspend state.

The following figure shows the connection between the module and the host.
Figure 4: Sleep Mode Application with USB Remote Wakeup
EG91_Series_Hardware_Design
Figure 3: Sleep Mode Application via UART
LTE Standard Module Series
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