Current-driven wire planning for electromigration avoidance in analog circuits

Electromigration due to insufficient wire width can cause the premature failure of a circuit. The ongoing reduction of circuit feature sizes has aggravated the problem over the last couple of years, especially with analog circuits. It is therefore an important reliability issue to consider current densities already in the physical design stage. We present a new methodology capable of routing analog multi-terminal signal nets with current-dependent wire widths. It is based on current-driven wire planning which effectively determines all branch currents prior to detailed routing. We also discuss successful applications of our methodology in commercial analog circuit design.