Analog and Mixed-Signal Layout Automation Using Digital Place-and-Route Tools

Abstract

Today’s analog and mixed-signal (AMS) layout flow requires long manual iterations and does not leverage computing resources for data-driven optimization. This issue is further compounded by the explosion of design rules and layout-dependent effects (LDEs). We present an AMS layout generation flow that leverages digital place-and-route (PnR) tools, amortizes setup cost with reusable primitives, and prunes layout candidates using a fast evaluation scheme. We also analyze LDEs and parasitics and investigate unique challenges and mitigation strategies associated with using digital PnR tools for AMS circuits. These insights are validated with a generated StrongARM comparator and a voltage-controlled oscillator (VCO). The VCO layout was optimized in 2 h and fabricated in 16-nm FinFET CMOS. Silicon measurement results of the VCO closely track the simulation, verifying the methodology from netlist to silicon.