# IR Drop Features

## Power Maps

Including 5 component：1. internal power: $power_i$, 2. switching power: $power_s$, 3. toggle rate scaled power: $power_{sca}$, 4. all: $power_{all}$, 5. time-decomposed power: $power_t$. They are generated with power report and timing window report from Innovus.

(1) Power report contains instance level power and toggles rate from a vectorless power analysis.

• Internal power ($p_i$)
• Switching power ($p_s$)
• Leakage power ($p_l$)
• Toggles rate ($r_{tog}$)

Then these instance level power is merged into corresponding tile to form power maps.

$power_i \propto p_i$
$power_s \propto p_s$
$power_{sca} \propto (p_i+p_s) \times r_{tog}+p_l$
$power_{all} \propto p_i+p_s+p_l$

(2) Timing window report contains possible switching time domain of the instance in a clock period from a static timing analysis for each pin. The clock period is decomposed evenly into 20 parts, and the cell contributes to power map $power_t$ only in the parts that it is switching.

$power_t[0,19] \propto p_{sca}$

## IR Drop Map

IR drop value on each node from a vectorless power rail analysis is merged into corresponding tile to form IR drop maps.