VLM-CAD: VLM-Optimized Collaborative Agent Design Workflow for Analog Circuit Sizing
Guanyuan Pan, Yugui Lin, Tiansheng Zhou, Pietro Liò, Shuai Wang, Yaqi Wang
TL;DR
VLM-CAD addresses the challenge of automatic analog circuit sizing by integrating a Vision-Language Model–driven collaborative agent workflow with schematic interpretation. It combines Image2Net for precise schematic annotation, a multi-agent circuit analysis pipeline, DC bias preparation, inference-based sizing, and ExTuRBO for explainable, warm-started optimization, producing a final design report with Global and Elite sensitivity insights. Empirical results on PTM-based amplifiers show a 100% success rate and fast runtimes for the relaxed design space, while highlighting the importance of schematic information for tractable optimization in tighter design spaces. The approach offers a path toward explainable, efficient, and industry-ready automated analog sizing that couples numeric optimization with model-based reasoning and trust-enhancing analysis.
Abstract
Analog mixed-signal circuit sizing involves complex trade-offs within high-dimensional design spaces. Existing automatic analog circuit sizing approaches often underutilize circuit schematics and lack the explainability required for industry adoption. To tackle these challenges, we propose a Vision Language Model-optimized collaborative agent design workflow (VLM-CAD), which analyzes circuits, optimizes DC operating points, performs inference-based sizing and executes external sizing optimization. We integrate Image2Net to annotate circuit schematics and generate a structured JSON description for precise interpretation by Vision Language Models. Furthermore, we propose an Explainable Trust Region Bayesian Optimization method (ExTuRBO) that employs collaborative warm-starting from agent-generated seeds and offers dual-granularity sensitivity analysis for external sizing optimization, supporting a comprehensive final design report. Experiment results on amplifier sizing tasks using 180nm, 90nm, and 45nm Predictive Technology Models demonstrate that VLM-CAD effectively balances power and performance, achieving a 100% success rate in optimizing an amplifier with a complementary input and a class-AB output stage, while maintaining total runtime under 43 minutes across all experiments.
