User's Manual

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HW Design Guidelines
An input to the POWER_ON pin shall trigger the transition from the Module
Disabled to the Module Enabled state. See figure6, a low pulse(tlow > 0s) on
POWER_ON pad will enable the module after VCC is applied.
An input to the POWER_ON pin shall trigger the transition from the Module
Enabled to the Module Disabled state. See figure6, after power on, a low pulse
(tlow > 2s) on POWER_ON pin will disable (power-off) the module.
Figure 4. Power ON/OFF timming
2.6.2. Wake-up interface
In applications where power consumption is a major factor in performance metrics (such as
battery-operated sensors that are based on IOT/M2M modem solution and also include a
third party host), it is necessary to define a simple interface that will allow both the modem
and the host to be able to enter low power states whenever possible and the other side to
wake it up once required.
For example, if the host has no data to transmit or any other tasks, it may enter some low
power state according to its own capabilities and configurations. If during that period the
host is in a low power state and the modem suddenly receives data, it must wake-up the
host.
A similar requirement exists from the other side. For example, if the modem is in a low
power state and suddenly the host must transmit data, it must be able to wake-up the
modem.
The interface consists of two signals: One is driven by the host and received by the modem;
the other is driven by the modem and received by the host.