Power Saving; Sleep Mode; Uart Application - Quectel EG91 Series Hardware Design

Mode
Airplane AT+CFUN command or W_DISABLE# pin can set the module to enter intoairplane
Mode mode. In this case, RF function will be invalid.
In this mode, the current consumption of the module will be reduced to the minimal level.

Sleep Mode

During this mode, the module can still receive paging message, SMS, voice call and
TCP/UDP data from the network normally.
In this mode, the power management unit shuts down the power supply. Software is not
Power Down
active. The serial interface is not accessible. Operating voltage (connected to VBAT_RF
Mode
and VBAT_BB) remains applied.
3.5.1. Sleep Mode
EG91 is able to reduce its current consumption to a minimum value during the sleep mode. The following
sub-chaptersdescribe the power saving procedures of EG91 module.

3.5.1.1. UART Application

If the host communicates with the module via UART interface, the following preconditions can let the
module enter into sleep mode.
 Execute AT+QSCLK=1commandto enable sleep mode.
 Drive DTR to high level.
The following figure shows the connection between the module and the host.
Driving the host DTR to low level will wake up the module.
EG91_Hardware_Design

3.5. Power Saving

Figure 3: Sleep Mode Application via UART
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LTE Module Series
EG91 Hardware Design