Telit Wireless Solutions ME910G1, Руководство по конструкции

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ME910G1 Hardware Design Guide
1VV0301593 Rev.12
Page 40 of 93 2021-09-24
Not Subject to NDA
Wake from Deep Sleep Mode
ME910G1 supports Power Saving Mode (PSM) functionality defined in 3GPP Release 12.
When Periodic Update Timer expires, ME910G1 power off until the next scheduled wake-
up time.
Host-controlled asynchronous event can wake up from deep sleep mode by asserting the
ON_OFF*/WAKE* pin LOW for at least 5 seconds.
The Host can detect deep sleep mode by pulling VAUX/PWRMON pin if previously
configured.
Unconditional Shutdown
HW_SHUTDOWN * is used to unconditionally shutdown the ME910G1 . Whenever this
signal is pulled low, the ME910G1 is reset. When the device is reset it stops any operation.
After the release of the line, the ME910G1 is unconditionally shut down, without carrying
out any disconnection from the network in which it is registered. This behaviour is not a
proper shut down because any cellular device is requested to issue a disconnection
request on turn off. The
HW_SHUTDOWN * is internally controlled on start-up to always
achieve a proper power-on reset sequence, so there's no need to control this pin on start-
up.
To unconditionally shutdown the ME910G1, the pad HW_SHUTDOWN* must be tied low
for at least 200 milliseconds and then released.
The signal is internally pulled up so the pin can be left floating if not used.
If used, it must always be connected with an open collector transistor, to allow the
internal circuitry the power on reset and under voltage lockout functions.
During PSM mode, the HW_SHUTDOWN toggle has no effect. The use of the
HW_SHUTDOWN* pin is valid only when the ME910G1 has VAUX/PWRMON output HI.
PIN DESCRIPTION
Signal Function I/O PAD
HW_SHUTDOWN* Unconditional Shutdown of the Module I R13
Table 19: HW_SHUTDOWN* signal
Warning: The unconditional hardware Shutdown must not be used
during the normal operation of the device since it does not disconnect
the device from the network. It shall be kept as an emergency exit
procedure.