做高速电路设计或EDA工具开发的团队，终于有办法把信号完整性优化从数天缩短到毫秒级——ANO直接学出优化策略而非反复迭代，值得在DDR5/SerDes等场景中试试。
本文提出了一种名为摊销神经优化（ANO）的方法，用于高速信号完整性（SI）分析的预布局设计空间探索。传统方法依赖迭代式黑箱优化算法，计算成本高昂，而ANO通过使用完全可微的神经网络代理模型，从代理中提取解析梯度来训练全局优化策略。训练完成后，ANO策略能在单次确定性前向传播中直接将不同通道上下文映射到接近最优的设计参数，从而消除了推理时的迭代过程。在DDR5 DFE、9维SerDes Tx/Rx联合均衡和DDR3 DQS差分对布线等复杂场景中，ANO相比实例特定黑箱算法仅牺牲约10%的最优性，却实现了三到四个数量级的加速。对于大规模32万实例的多角SerDes扫描优化，ANO将原本需要数天的计算压缩为毫秒级的单次批量前向传播，将计算密集的SI优化转变为实时交互式预布局设计空间探索。
Amortized Neural Optimization for Pre-Layout Signal Integrity Design Space Exploration using Differentiable Surrogates
Pre-layout design space exploration (DSE) for high-speed signal integrity (SI) analysis is often limited by the computational cost of simulations and iterative optimization algorithms within modern electronic design automation (EDA) workflows. While machine learning surrogate models accelerate the simulation step, optimizing designs still requires utilizing iterative black-box search methods. This iterative nature scales poorly, making multi-corner sweeps computationally expensive. As a solution, this paper proposes amortized neural optimization (ANO) for pre-layout SI design. ANO entirely eliminates iterative black-box inference by utilizing fully differentiable neural network surrogate models. ANO extracts analytical gradients from the surrogate to train a global optimization policy. Instead of solving the optimization problem repeatedly at inference, the optimization process is learned offline and therefore amortized. Once the ANO policy is trained, it maps different channel contexts directly to near-optimal design parameters in a single deterministic forward pass. The efficiency and accuracy of the ANO framework are demonstrated based on three complex SI design scenarios, including DDR5 decision feedback equalization (DFE), 9-dimensional SerDes Tx/Rx co-equalization, and DDR3 DQS differential pair routing to optimize eye diagram metrics under intra-pair skew constraints. By trading roughly 10% in optimality compared to instance-specific black-box algorithms, it realizes speedups of three to four orders of magnitude. For a large-scale 320,000-instance multi-corner SerDes sweep optimization, ANO collapses what would have taken days of computation using iterative search algorithms into a single batched forward pass that completes in milliseconds. This transforms computationally expensive SI optimization into real-time and interactive pre-layout DSE.