_{CCO}current requirements, which is critical for a thorough estimation. The same estimation also generates the thermal loading information needed for thermal simulation. Either your Vitis or Vivado design should be appropriately constrained for power based on the results of the estimation and thermal analysis.

An accurate
power estimation is critical to defining an effective thermal solution and keeping
the K26 SOM components below their
maximum junction temperature (T_{j}). When designing the
K26 SOM thermal solution, the
worst-case power is the starting point for simulation. Once a thermal solution is
defined and the T_{j} is within the limits, the theta J_{A} (ϴJ_{A}) of the system can be
input back into the PDM for a more accurate estimation of the power requirements for
the K26 SOM.

Based on the temperature grade of the commercial temperature
grade K26C SOM or the industrial
temperature grade K26I SOM, the
junction temperature should be forced to the maximum desired operating temperature
(often maximum device operating temperature) to get the worst-case power estimation
for the K26 SOM. The following
example shows the K26C SOM when the
T_{j} is forced to 85°C. The power dissipation of each
of the components on the SOM is shown in the Thermal Loading table.

In this example:

- T
_{j}is forced to the maximum allowed for the K26C SOM (85°C) - Maximum process is selected to get the worst-case static power
- The thermal power of the SOM components
- Total electrical power required on the SOM 5V connector is based on the current estimation

The thermal loading in the PDM matches the components in the SOM thermal model, the thermal power for every component listed should be added. The PCB also has a small amount of power loss to account for an inductor or other ancillary components, this power should be applied to the PCB in the model.

Once a capable thermal solution is designed and validated in thermal simulation, the power estimation can be refined using the simulation results.

- Apply the calculated effective ϴJ
_{A}of the system in the PDM along with the maximum supported T_{a}for the product. This is the recommended approach because the power estimation dynamically estimates the anticipated T_{j}and provides a more accurate estimated power.

_{A}is a measure of how the junction temperature (T

_{j}) will increase above the ambient temperature (T

_{A}) for every watt of power dissipated (P

_{d}) in the device, the units are °C/W. ϴJ

_{A}is calculated using the following equation: ϴJ

_{A}= (T

_{j}– T

_{A})/ P

_{D}.

The following
example shows a T_{A} of 25°C with a ϴJ_{A} of 3.9°C/W and the estimate T_{j} based on the
current estimation is 52°C, which is a more accurate total power estimation for the
SOM. The total power at 52°C is 8.7W, compared to 9.7W at 85°C in the worst-case
estimate.

```
set_operating_conditions -design_power_budget <Power in Watts>
set_operating_conditions -process maximum
set_operating_conditions -ambient_temp <Max Supported by Application>
set_operating_conditions -thetaja <Increase in Tj for every W dissipated C/W>
```