# DAEDALUS

Mixed-signal 3-SAT solver. **Venue:** ISSCC 2025 • JSSC 2025.

DAEDALUS is a 50-variable 3-SAT solver in TSMC 28nm. Accepts problems directly without preprocessing and achieves 100% solvability on SATLIB benchmarks: 1.6 µs for 20-variable problems, 31.7 µs for 50-variable. 3,000× faster and 14,000× more energy-efficient than WalkSAT on an AMD Threadripper.

## Architecture

Each variable maps to a relaxation oscillator spin; clauses are NOR3 gates in a feedback network. Twin analog/digital crossbars provide unrestricted all-to-all 3-SAT connectivity—any variable can appear in any clause without decomposition. When a clause is unsatisfied, current injection rotates spins toward a satisfying assignment. When all clauses are satisfied, the system freezes at a solution.

## Key Innovation

Dynamic Continuous-Time Injection activates spin oscillation only when feedback is present. This reduces solution time by 6× and energy by 8× compared to continuously oscillating nodes, while eliminating complex sampling circuitry—spins freeze at the final solution.

## Results

Tested on all 1,000 problems in the 20-variable and 50-variable SATLIB benchmarks, 100 runs each, with 100% solvability. 0.58 mm².

- [ISSCC 2025 paper (PDF)](/portfolio/pdf/daedalus-conference.pdf)
- [JSSC 2025 paper (PDF)](/portfolio/pdf/daedalus-journal.pdf)