RXi2-BP Hardware Reference Manual
Section 8
GFK-3187B
November 2020
Thermal Performance
33
Once the T
CRIT
threshold is exceeded, the system will try to shut down within 500ms into S5.
Figure 27: Thermal Zone Tactive to Thot to Tcrit
Temp
SMB-Alert
LED Red
Thot
OS
SMBus
Exp
TZ: Active
Tactive
Tcrit
THRM
LED Green
Note: Thermal Zone
‘
Active
’
is optional and not implemented in the RXi2-BP fanless design.
If the system is rebooting while the overtemperature situation is still present, the system will be shut
down again after handing over to the operating system. However, this depends on how the operating
system is configured. In case of questions, please contact Emerson support.
This could cause unbootable SSDs and other data loss, and therefore it is highly recommended to
resolve overtemperature situations before rebooting the system.
8.2
Thermal Design Strategy
Having many parameters that influence the thermal performance of an IPC makes it difficult to perform
thermal design by simply analyzing thermal test data and specifications.
The recommended way to assess thermal performance is to test the real software application, or a
good approximation of it, in an environment that would be the worst-case for the real use scenario.
This typically means static air, no airflow at all.
Note that typical thermal test chambers have a significant internal airflow, which results in higher
thermal performance levels than those observed in real installations.
8.2.1
Thermal Guidance
The following is thermal guidance for the different RXi2-BP processor SKUs. It is based on zero airflows,
and even a slight movement of air will dramatically increase the operating temperature range.
The graph below shows the maximum ambient temperature range, based on CPU SKU and application
workload. Note that the lower temperature limit is not affected by application software load and purely
depends on the product SKU as stated in the specification section.
