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HUAWEI ME909u-521 LTE LGA Module
Hardware Guide
Description of the Application Interfaces
Issue 05 (2017-12-15)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
31
3.4.4 WAKEUP_IN Signal
WAKEUP_IN pin is the authorization signal of ME909u-521 module entering sleep
mode.
If the signal is pulled up to high level (1.8 V), ME909u-521 module cannot enter sleep
mode. If this pin is not connected, it will keep in low level by default.
Table 3-3 shows the definition of the WAKEUP_IN signal.
Figure 3-9
Connections of the WAKEUP_IN pin
The pull up resistor should not be greater than 22 k
Ω.
3.4.5 WAKEUP_OUT Signal
The WAKEUP_OUT signal is used to wake up the external devices. Its drive current is
no more than 2 mA.
Table 3-3 shows the definition of the WAKEUP_OUT signal.
The WAKEUP_OUT pin outputs a low-level voltage by default. When a wake-up
source arrives, this pin outputs a high-level-voltage pulse lasting for 1s, during which if
other wake-up sources arrive, the module will ignore the later wake-up requests. In
other words, the module will not output a second pulse in this 1s.