Design-Space Exploration for Macro-Based SRAM Configuration on the SKY130 PDK

Abstract

The SKY130 Macro Memory Cell Generator interleaves three fixed PDK macro sizes into custom SRAM arrays but evaluates no candidates: memory type and placement style are chosen once, with no automated comparison. This paper replaces that manual step with a search across nine memory-type and placement combinations, scored on die area, static leakage, and estimated half-perimeter wirelength (HPWL). A constraintaware variant of the same search accepts a maximum die width and height and returnsthe best candidate that fits, rather than the unconstrained optimum. Area comes from the baseline tool's own placement routine, not a closed-form estimate. Candidate selection moves away from a bare minimum-area rule to a Pareto-optimality filter with a documented weighted tie-break, benchmarked against five other established selection rules — weighted-sum, TOPSIS, rank-sum, lexicographic ordering, and naive minimum-area — across fifteen realistic design sizes (4 KB–1 MB). All six methods agreed completely on only four of fifteen sizes (26.7%), showing that selection-method choice is not a formality.