Setting Power and Current Budget for Xilinx Devices - 2020.2 English

Vivado Design Suite User Guide: Power Analysis and Optimization (UG907)

Document ID
UG907
Release Date
2020-11-24
Version
2020.2 English

It is a good practice to specify the power and supply current budget for your design before generating the power report. The design power budget is the power budget for the entire device while the current budget is specified per power supply or power rail. Use the following commands to specify the power and supply current budget:

set_operating_condition -design_power_budget <Power in Watts>
set_operating_conditions -supply_current_budget {<power supply name> <current budget in Amp>}

While running Report Power, the design power and the individual power supply current are compared with this power and supply current budgets. Report Power (GUI/Text) indicates the power budget margin. It displays the positive margin if the design power is less than the power budget or a red negative margin, if design power exceeds power budget. If you have not provided a power budget, the report displays N/A for the margin. The following figure shows the power report when you do not specify any design power budget:

Figure 1. Power Report Without Design Power Budget

The following figure shows the power report when the design power budget is specified as 4 Watts and power margin is positive. It also displays the power margin in a negative state when the design power budget is specified as 2 Watts.

Figure 2. Power Report With Power Budget at Positive and Negative Margins

The supply current budget for each power supply is displayed in the Power Supply section. For each supply, Report Power displays positive margin when the supply current is less than the specified budget and a negative margin appears in red when supply current exceeds the specified current budget. If the current budget is not specified for any supply, then Report Power displays the current budget as unspecified and margin as N/A for that supply rail as shown in the following figure:

Figure 3. Supply Current Budget