Undervoltage Shutdown - Quectel UG89 Hardware Design

of UG89. After expiry of the 2 minute guard period, the presentation of URCs will be disabled, i.e. no
URCs with alert levels "1" or ''-1" will be generated.
URCs indicating the level "2" or "-2" are instantly followed by an orderly shutdown. The presentation of
these URCs is always enabled, i.e. they will be output even though the factory setting AT+SCTM=0* was
never changed.
Please refer to document [2] for details about AT+SCTM* command.
The maximum temperature ratings are stated in Section 5.3. Refer to Table 12 for the associated URCs.
Table 10: Temperature dependent behavior
Sending temperature alert (2min after UG89 start-up, otherwise only if URC presentation enabled)
^SCTM_B: 1
^SCTM_B: -1
^SCTM_B: 0
Automatic shutdown (URC appears no matter whether or not presentation was enabled)
^SCTM_B: 2
^SCTM_B: -2

3.6.4.2. Undervoltage Shutdown*

The undervoltage shutdown threshold is the specified minimum supply voltage VBAT given in Table 23.
When the average supply voltage measured by UG89 approaches the undervoltage shutdown threshold
(i.e., 0.05V offset) the module will send the following URC:
^SBC: Undervoltage Warning
The undervoltage warning is sent only once until the next time the module is close to the undervoltage
shutdown threshold.
If the voltage continues to drop below the specified undervoltage shutdown threshold, the module will
send the following URC:
^SBC: Undervoltage Shutdown
This alert is sent only once before the module shuts down cleanly without sending any further messages.
This type of URC does not need to be activated by the user. It will be output automatically when fault
conditions occur.
UG89_Hardware_Design
Board close to overtemperature limit.
Board close to undertemperature limit.
Board back to non-critical temperature range.
Alert: Board equal or beyond overtemperature limit. UG89 switches off.
Alert: Board equal or below undertemperature limit. UG89 switches off.
UMTS/HSPA+ Module Series
UG89 Hardware Design
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