Usb Application - Quectel EC200U Series Hardware Design

In this case, three preconditions can make the module enter the sleep mode.
⚫
Execute AT+QSCLK=1 to enable sleep mode.
⚫
Ensure the MAIN_DTR is held at high level, or keep it open.
⚫ Ensure the host's USB bus, which is connected with the module's USB interface, enters suspended
state.
The following figure shows the connection between the module and the host.
⚫
Sending data to the module through USB can wake up the module.
⚫
When the module has a URC to report, the URC will trigger the behaviors of MAIN_RI pin.
NOTE
1. USB suspend is supported on Linux system but not supported on Windows system.
2. Pay attention to the level match shown in dotted line between the module and the host.

3.5.1.4. USB Application

If the host does not support USB suspend function, USB_VBUS should be disconnected via an external
control circuit of USB_VBUS to let the module enter sleep mode.
⚫
Execute AT+QSCLK=1 to enable sleep mode.
⚫
Ensure the MAIN_DTR is held at high level, or keep it open.
⚫
Disconnect USB_VBUS.
The following figure shows the connection between the module and the host.
EC200U_Series_Hardware_Design
Module
USB_VBUS
USB_DP
USB_DM
AP_READY
MAIN_RI
GND
Figure 5: Sleep Mode Application with MAIN_RI
LTE Standard Module Series
Host
VDD
USB_DP
USB_DM
GPIO
EINT
GND
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