Solution Space Exploration

Solution Space Exploration

Properly evaluating serial link design tradeoffs requires running thousands of simulation experiments to explore different combinations of design parameters. Running this many simulations efficiently requires automatic generation and execution of simulation cases, along with automatic post-processing of simulation output to extract and summarize key design metrics. Quantum Channel Designer completely automates the process of Solution Space Exploration, allowing designers to study the interactions of dozens of design parameters, co-optimizing the channel design and SerDes IP configuration to arrive at a globally optimized solution.

 

Designers capture channel designs graphically in Quantum Channel Designer by dragging and dropping channel elements into their schematic. Channel elements include TX/RX SerDes IP, parasitic elements, sub-circuit definitions and S-parameter blocks. Users can vary any parameter of the captured channel design - for example, transmission line length, trace cross sectional characteristics or line-to-line spacing. QCD allows design variables to be swept independently or to be considered as correlated data, with values specified on a case by case basis. 

 

 

Effective serial link analysis requires the ability to use S-parameter data quickly and efficiently. Quantum Channel Designer lets designers import S-parameter data sets and associate them with blocks in their channel design. Designers can associate multiple sets with a single block in their schematic and sweep through alternates automatically during simulation.

 

 

 

 

The IBIS-AMI specification enables high-performance, interoperable models for SerDes IP. Quantum Channel Designer provides native support for IBIS-AMI, using models directly without translation. When an IBIS-AMI model is placed in the schematic, QCD displays associated model parameters in the GUI, allowing designers to specify parameters values used for simulation. Tap coefficients, equalization and clock recovery modes can swept along with other channel parameters to determine the optimum overall design solution.

 

 

 

 

Automated analysis and Post-processing

Quantum Channel Designer lets designers control the tradeoff between the size of the explored solution space and simulation run time. As designers specify swept design parameters, Quantum Channel Designer displays how many simulations will be required. This makes it easy for designers to determine which experiments can be run interactively and which experiments are better suited for batch analysis. When simulation is launched, QCD automatically generates the required simulation cases, runs simulations and post-processes simulation results to extract standardized design metrics. Simulation results are presented in spreadsheet format along with the conditions that generated them, allowing designers to quickly sort and filter data to identify cases of interest. Graphical simulation results (waveforms) are saved for all simulation cases and can be displayed on demand.