Simulation has become a requirement for ASIC development. The cost of creating an actual chip is high as is the turnaround time to make corrections. A chip needs to work the first time. Chip simulation allows designs to be tested before they hit silicon.
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The challenge is not just making the transistors work, because the software needs to work as well. Instruction-set simulators can provide cycle-accurate simulation that is significantly faster than a low-level simulation. Peripheral simulation is important for embedded applications and the latest crop of simulators makes this possible, taking developers closer to the final system.
Churning out prototypes is much easier these days with low-cost FPGAs and 3D printers. Still, simulation is faster and cheaper. It is much better to rebuild a simulated device and retest it. Here, the challenge is providing sufficient fidelity so that the simulation provides an accurate rendition of the end environment.
This approach has been used in large projects such as aircraft design. The cost can be justified because in the long run it is significantly more economical. In general, the simulation issues are related to software and the hardware that runs this software. The costs of both are going down as the performance is increasing, making it more practical to use by more designers.
For example, Dura Automotive Systems used Dassault Systemes’ Solidworks design tools and the Simulia simulation system to design and simulate the sliding French salon doors for a car (see the figure). The simulation addressed the mechanical, electrical, and software environments.
The design was a challenge from a mechanical, electrical, and software perspective. The doors needed to be lightweight and have no external tracks. They have a 20% wider egress opening than conventional doors, along with a 40% weight reduction. The system employs a hands-free command system with an advanced obstacle detection system. Dura’s aluminum door design includes glass fiber reinforced composites.
The simulation environment allows testing of the mechanical aspects through the software and sensors that control the door. A simulated person allows repeated obstacle testing. It can guarantee that the system meets consumer and government requirements prior to physical testing.
Physical testing is still required but if the majority of tests can be simulated instead, then costs can be significantly reduced. Simulations can also be faster and done in parallel, thereby allowing more testing.
The use of simulation continues to grow as does the range and fidelity of the simulated environment. New embedded application areas like wearable technology will benefit from more robust physical and software simulation. The question will be whether simulation will be sufficient to reduce the amount of physical certification required for products.