ePnR

ePnR is a simple Integrated Circuit (IC) block standard cell placement & routing tool. ePnR currently supports only circuit blocks using equal height standard cells arranged in one or more channels of user configurable length. Standard cells are described in a simple text based library (compliant with eLogSim). Placement follows initially the cell call order in the SPICE like circuit input netlist. However, a placement optimization, aiming at minimum weighted accumulated wire length, by simulated annealing is available. Routing consists of channel routing as first step. If un-routed connections are left, Maze routing can (optionally) be applied. ePnR does not guarantee completely finished routing. However, un-routed connections will be left with rubberband connections and marked start and end points for subsequent manual routing using a third party layout editor. ePnR outputs in CIF 2.0 and GDS stream format readable by e.g. the free KLayout editor.