User's Manual

MC46 Hardware Interface Description
DRAFT
MC46_HD_V02.8xb Page 34 of 98 21.08.2003
Table 6: Temperature dependent behavior
Sending temperature alert (15 s after start-up, otherwise only if URC presentation enabled)
^SCTM_A: 1 Caution: T
amb
of battery close to overtemperature limit.
^SCTM_B: 1 Caution: T
amb
of board close to overtemperature limit.
^SCTM_A: -1 Caution: T
amb
of battery close to undertemperature limit.
^SCTM_B: -1 Caution: T
amb
of board close to undertemperature limit.
^SCTM_A: 0 Battery back to uncritical temperature range.
^SCTM_B: 0 Board back to uncritical temperature range.
Automatic shutdown (URC appears no matter whether or not presentation was enabled)
^SCTM_A: 2 Alert: T
amb
of battery equal or beyond overtemperature limit. MC46 switches off.
^SCTM_B: 2 Alert: T
amb
of board equal or beyond overtemperature limit. MC46 switches off.
^SCTM_A: -2 Alert: T
amb
of battery equal or below undertemperature limit. MC46 switches off.
^SCTM_B: -2 Alert: T
amb
of board equal or below undertemperature limit. MC46 switches off.
3.3.3.2 Temperature control during emergency call
If the temperature limit is exceeded while an emergency call is in progress the engine
continues to measure the temperature and to deliver alert messages, but deactivates the
shutdown functionality.
Once the call is terminated the temperature control will be resumed. If the temperature is still
out of range MC46 switches off immediately.
3.3.3.3 Undervoltage shutdown if battery NTC is present
In applications where the module’s charging technique is used and an NTC is connected to
the BATT_TEMP terminal, the software constantly monitors the applied voltage. If the
measured battery voltage is no more sufficient to set up a call the following URC will be
presented:
^SBC: Undervoltage.
The message will be reported, for example, when you attempt to make a call while the
voltage is close to the critical limit and further power loss is caused during the transmit burst.
To remind you that the battery needs to be charged soon, the URC appears several times
before the module switches off.
To enable or disable the URC use the AT^SBC command. The URC will be enabled when
you enter the write command and specify the power consumption of your GSM application.
Step by step instructions are provided in [1].