CAPHE Circuit Simulator IPKISS.eda

CAPHE is an extremely flexible and fast photonic circuit simulator. It simulates circuits and systems with thousands of components, both in frequency and time-domain and easily handles highly nonlinear devices. CAPHE can be used in a layout-driven and schematic driven design flow. It can be used for quick feasibility studies as well as component reliability&variability analysis. It is part of IPKISS.eda and integrated in S-Edit, L-Edit from the Tanner/Mentor design flow from Siemens.

  • Consistent and accurate: Full coupling with layout and smart physical simulation models
  • A Library of built-in models of standard photonic components from the IPKISS PICAZZO library
  • Flexible: create and extend your own circuit models with proprietary parameters or measurement data.
  • P+ EDA Integration in S-Edit for schematic driven design and layout driven verification.
  • Fast and ready for large circuits for noise, variability analysis and optimization.


Key features

Frequency-domain simulation
  • Passive devices
  • Bidirectionality: Caphe is a fully bidirectional simulator: check how backreflections impact your circuit impact performance, introduce loss or unwanted oscillations in the frequency spectrum
  • Very large optical circuits of over 10k components
Time-domain simulation
  • Circuits including nonlinear devices such as SOAs, modulators, photodetectors and so on.
  • Full bidirectionality
  • Write your own nonlinear models based on ODE (ordinary differential equations) equations, and integrate them into your circuits
  • Very large optical circuits of over 10k components
Circuit models
  • S-parameters: equation based, based on measurement, or based on physical device simulation results
  • Nonlinear, time-dependent models through ODEs (ordinary differential equations)
  • Switch between circuit models to easily assess the quality of different models
  • Circuit models are written in Python and compiled on-the-fly, which makes it very easy to create, debug, and deploy new models
Variability analysis
  • Run monte-carlo simulations
  • Analyze the results using Python's rich ecosystem of visualization and scientific libraries.
Model extraction
  • Extract model parameters by parametrizing a monitoring circuit and comparing with measurement results
  • Use Python's rich ecosystem of scientific tools (data analysis, optimization techniques, ...) to finetune towards your application
Smart Physical Model integration
  • Full flow automation from component layout to physical device simulation
  • Store the simulation recipes alongside the component definition for reproducibility
  • Integrate the simulation results in a circuit model for the device
Photonic and EDA integration
  • Draw schematic in S-Edit, and directly run simulations in Caphe (for selected PDKs)

Integration in the Tanner design flow by Siemens

PIC designers need full control of their design framework to ensure that the IC they fabricate exactly matches their design.

The biggest challenge is variability: Nanometer-level variations on a critical dimension at 200nm have a significant influence on the optical behavior. CAPHE efficiently simulate circuits that account for fabrication variability effects. The simulation and layout models are part of a single PCell.
Through Smart Physical Simulation, layout can be exported to physical solvers and seamlessly imported in circuit simulation.
Every change or variation in layout is therefore immediately reflected in simulation.

CAPHE in IPKISS.eda therefore uses the Tanner framework by Siemens to couple with S-Edit.


Compact models for accurate CAPHE simulations

CAPHE in the IPKISS 3.2 platform now provides a perfect framework for the model and library builder. Circuit builders need to scale their design flow - either by building a circuit from layout- either by starting from a schematic and by taking it to layout.
Today’s challenge is that no standard simulation models exist. On top very few FABS provide large measurements sets to populate the models with meaningful parameter values.
In many cases, the model and library builders will have to resort to creating and verifying their own models.
In CAPHE we have set up a complete flow for the generation and continuous improvement of compact simulation models:
Using Smart Physical Simulation, the layout can be ported to physical simulation and the results can be turned into a compact model for circuit simulation. By starting from layout, we ensure a flow, where all layout and technical stack data is exactly transferred to physical simulation. The simulation results reflect the exact layout.
In a later design stage, the PICs come back for measurement. These can be used to improve the simulation models
Finally, noise and variability models can be added using the unique Python framework so that yield and circuit variability can be studied.


Starting from our extensive validated component library, we can assist you in the creation and validation of new model libraries