Re: How to calculate the power stripes in encounter 10 point
Hi,
In general, you need to get current density allowed by the stripe metal layer, d info. from the foundry documentation (units A/m), the power voltage needed in your process (i.e. VDD if VSS = 0 volts) and an estimate of the power consumed by your design (I think the tools calculate this based on the cells used).
Roughly, the average current, Iave can be derived from the standard P = I * V formulae using the data above.
From this, we can get the total widths needed for the stripes using:
Iave = Total width of stripes * d .
So if total width of stripes needed is 100um and we want to use stripes of 10um width, then we need to use 10 stripes. However, if we calculate by saying we want to put 8 stripes only, each stripe should be at least 12.5um wide.
Since this calculation is a rough estimate, better add an extra stripe or widen by, say 10%.
A floorplan IR analysis will confirm if your stripes are sufficient.
Best regards.