can any one explain me about the footprint in the standard cell synopsys timing library .lib
why they are used, i observed that they are same for all the stdcell with similar functionality
Please do post some related documents related to this
They are the same for cells with the same function because it makes it easier for a physical synthesis tool to swap cells of the same function to meet timing and slew.
Without that the tool would have to verify the function of the cell each time it wanted to change the cell.