LPM2100 mg NB Module Hardware User Guide
Shanghai Yuge Information Technology Co., Ltd.
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The module serial port TTL is the IO output level value. If the serial port needs to be
connected to the 3.3V level MCU, an external level conversion chip needs to be added
externally to achieve level matching. The chip connection method can refer to the following
circuit
：
Figure 3-12 UART level conversion circuit
3.6 Power saving technology
LPM2100 mg supports three power saving modes
：
PSM (Power Saving Mode)
DRX (Discontinuous Reception)
eDRX (Extended DRX, extended discontinuous reception mode)
3.6.1 PSM
The main purpose of the PSM function is to reduce module power consumption and
extend battery life. The module consumes a maximum of 5uA in PSM mode.
Suitable for services that have no delay requirement for downlink data, adopt
battery-powered methods, such as meter reading services.
The process of the module entering the PSM is as follows: When the module establishes
a connection with the network or updates the location tracking area (TAU), it will apply to
enter the PSM in the request message, and the network configures the T3324 timer value
return module and starts the timer. When the T3324 timer expires, the module enters the PSM.
The module cannot apply to enter the PSM mode during emergency services or when
initializing the public data network.
