SPICEMixer - Netlist-Level Circuit Evolution

TL;DR

SPICEMixer is a genetic algorithm that evolves SPICE netlists directly, enabling flexible circuit synthesis with improved efficiency and compatibility with various components and subcircuits.

Contribution

It introduces a netlist normalization technique and genetic operators applied directly at the netlist level for general-purpose circuit evolution.

Findings

Successfully synthesizes standard cells and OpAmps.

Matches or exceeds recent synthesis methods in performance.

Requires fewer simulations than existing approaches.

Abstract

We present SPICEMixer, a genetic algorithm that synthesizes circuits by directly evolving SPICE netlists. SPICEMixer operates on individual netlist lines, making it compatible with arbitrary components and subcircuits and enabling general-purpose genetic operators: crossover, mutation, and pruning, all applied directly at the netlist level. To support these operators, we normalize each netlist by enforcing consistent net naming (inputs, outputs, supplies, and internal nets) and by sorting components and nets into a fixed order, so that similar circuit structures appear at similar line positions. This normalized netlist format improves the effectiveness of crossover, mutation, and pruning. We demonstrate SPICEMixer by synthesizing standard cells (e.g., NAND2 and latch) and by designing OpAmps that meet specified targets. Across tasks, SPICEMixer matches or exceeds recent synthesis methods while requiring substantially fewer simulations.