u-blox SARA-G3 Series, Руководство по системной интеграции

Страница: 80 / 218

SARA-G3 series - System Integration Manual
UBX-13000995 - R06 Objective Specification System description
Page 80 of 218
1.13.8 Smart temperature management
Wireless modules – independent of the specific model – always have a well-defined operating temperature
range. This range should be respected to guarantee full device functionality and long life span.
Nevertheless there are environmental conditions that can affect operating temperature, e.g. if the device is
located near a heating/cooling source, if there is/is not air circulating, etc.
The module itself can also influence the environmental conditions; such as when it is transmitting at full
power. In this case its temperature increases very quickly and can raise the temperature nearby.
The best solution is always to properly design the system where the module is integrated. Nevertheless an
extra check/security mechanism embedded into the module is a good solution to prevent operation of the
device outside of the specified range.
1.13.8.1 Smart Temperature Supervisor (STS)
The Smart Temperature Supervisor is activated and configured by a dedicated AT+USTS command. Refer
to
u-blox AT Commands Manual [2] for more details.
The wireless module measures the internal temperature (Ti) and its value is compared with predefined
thresholds to identify the actual working temperature range.
Temperature measurement is done inside the module: the measured value could be different from
the environmental temperature (Ta).
Warning
area
t
-1
t
+1
t
+2
t
-2
Valid temperature range
Safe
area
Dangerous
area
Dangerous
area
Warning
area
Figure 23: Temperature range and limits
The entire temperature range is divided into sub-regions by limits (see Figure 23Figure 23 ) named t
-2
,
t
-1
, t
+1
and t
+2
.
 Within the first limit, (t
-1
< Ti < t
+1
), the wireless module is in the normal working range, the Safe
Area

In the Warning Area, (t
-2
< Ti < t
.1
) or (t
+1
< Ti < t
+2
), the wireless module is still inside the
valid temperature range, but the measured temperature approaches the limit (upper or lower). The
module sends a warning to the user (through the active AT communication interface), which can
take, if possible, the necessary actions to return to a safer temperature range or simply ignore the
indication. The module is still in a valid and good working condition
 Outside the valid temperature range, (Ti < t
-2
) or (Ti > t
+2
), the device is working outside the
specified range and represents a dangerous working condition. This condition is indicated and the
device shuts down to avoid damage