Cadence AMS仿真收敛问题解决建议

1. 评估并解决任何通知、警告或错误消息。
2. 使用真实的器件模型。检查所有器件参数，特别是非线性器件模型参数，确保它们是合理的。
3. 连接到高阻抗节点的小浮空电阻会导致收敛困难。避免使用非常小的浮空电阻，尤其是半导体中的小寄生电阻。相反，使用电压源或探针来测量电流。
4. 确保非线性器件上使用一整套寄生电容，避免解波形出现跳变。在 MOS 模型上，指定非零源极和漏极区域。
5. 使用参数范围检查器（使用 “+param param-limits-file” 作为命令行参数）对参数值执行完整性检查，并注意任何警告。使用“info”分析打印最小和最大参数值。确保给定的范围，例如模型、输出、温度相关和工作点（如果可能）参数是合理的。
6. 检查独立和非独立电流源的方向。如果连接电流源以迫使电流反向通过二极管，则可能会导致收敛问题。
7. 通过设置选项“diagnose=detailed”启用诊断消息。
8. 使用“cmin”参数在电路中的每个节点到地之间安装一个小电容器。这通常会消除解决方案中的任何跳跃。
9. 放宽公差，尤其是绝对公差，如“iabstol”（在选项声明中）。如果公差设置得太紧，它们可能会妨碍收敛。
10. 尝试简化非线性器件模型，以避免可能导致模型收敛问题的区域。

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1. Evaluate and resolve any notice, warning, or error messages.
2. Use realistic device models. Check all component parameters, particularly nonlinear device model parameters, to ensure that they are reasonable.
3. Small floating resistors connected to high impedance nodes can cause convergence difficulties. Avoid very small floating resistors, particularly small parasitic resistors in semiconductors. Instead, use voltage sources or iprobes to measure current.
4. Ensure that a complete set of parasitic capacitors is used on nonlinear devices to avoid jumps in the solution waveforms. On MOS models, specify nonzero source and drain areas.
5. Perform sanity check on the parameter values by using the parameter range checker (use ‘+param param-limits-file’ as a command line argument) and heed any warnings. Print the minimum and maximum parameter value by using ‘info’ analysis. Ensure that the bounds given for instance, model, output, temperature-dependent, and operating-point (if possible) parameters are reasonable.
6. Check the direction of both independent and dependent current sources. Convergence problems might result if current sources are connected such that they force current backward through diodes.
7. Enable diagnostic messages by setting option ‘diagnose=detailed’.
8. Use the ‘cmin’ parameter to install a small capacitor from every node in the circuit to ground. This usually eliminates any jump in the solution.
9. Loosen tolerances, particularly absolute tolerances like ‘iabstol’ (on options statement). If tolerances are set too tight, they might preclude convergence.
10. Try to simplify the nonlinear component models to avoid regions that might contribute to convergence problems in the model.