EES3 Hardware Interface Description
3.3 Power Up / Power Down Scenarios
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EES3_HD_v01.100b
Page 37 of 118
2009-08-12
Confidential / Released
3.3.4.1
Thermal Shutdown
The board temperature is constantly monitored by an internal NTC resistor located on the PCB.
The NTC that detects the battery temperature must be part of the battery pack circuit as de-
scribed in
The values detected by either NTC resistor are measured directly on
the board or the battery and therefore, are not fully identical with the ambient temperature.
Each time the board or battery temperature goes out of range or back to normal, EES3 instantly
displays an alert (if enabled).
•
URCs indicating the level "1" or "-1" allow the user to take appropriate precautions, such as
protecting the module from exposure to extreme conditions. The presentation of the URCs
depends on the settings selected with the AT^SCTM write command:
AT^SCTM=1: Presentation of URCs is always enabled.
AT^SCTM=0 (default): Presentation of URCs is enabled during the 2 minute guard period
after start-up of EES3. After expiry of the 2 minute guard period, the presentation 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, except
in cases described in
. 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.
The maximum temperature ratings are stated in
. Refer to
for the associated
URCs.
Table 9:
Temperature dependent behavior
Sending temperature alert (2min after EES3 start-up, otherwise only if URC presentation enabled)
^SCTM_A: 1
Caution: Battery close to overtemperature limit.
^SCTM_B: 1
Caution: Board close to overtemperature limit, i.e., board is 5°C below overtem-
perature limit.
^SCTM_A: -1
Caution: Battery close to undertemperature limit.
^SCTM_B: -1
Caution: Board close to undertemperature limit, i.e., board is 5°C above under-
temperature limit.
^SCTM_A: 0
Battery back to uncritical temperature range.
^SCTM_B: 0
Board back to uncritical temperature range, i.e., board is 6°C below its over- or
above its undertemperature limit.
Automatic shutdown (URC appears no matter whether or not presentation was enabled)
^SCTM_A: 2
Alert: Battery equal or beyond overtemperature limit. EES3 switches off.
^SCTM_B: 2
Alert: Board equal or beyond overtemperature limit. EES3 switches off.
^SCTM_A: -2
Alert: Battery equal or below undertemperature limit. EES3 switches off.
^SCTM_B: -2
Alert: Board equal or below undertemperature limit. EES3 switches off.
