Product Info

LTE Standard Module Series

EC25 Series Hardware Design

EC25_Series_Hardware_Design 40 / 134

The following figure shows the connection between the module and the host.

RXD

TXD

DTR

AP_READY

TXD

RXD

EINT

GPIO

Module

Host

GND

Figure 3: Sleep Mode Application via UART

⚫ Driving the host DTR to low level will wake up the module.

⚫ When EC25 has a URC to report, RI signal will wake up the host. Please refer to Chapter 3.19 for

details about RI behaviors.

⚫ AP_READY will detect the sleep state of the host (can be configured to high level or low level

detection). Please refer to AT+QCFG="apready" command 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 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 suspend state.

The following figure shows the connection between the module and the host.

USB_VBUS

USB_DP

USB_DM