This paper demonstrates how an accurate high order model of a MEMS device can be used for efficient system design. Leveraging analyses and functionality available in commercial EDA tools, a methodology for coupled, multi-physics simulation essential to MEMS and IC design is presented within the context of a MEMS accelerometer controlled by a sigma-delta modulator.

This paper reports a novel model-order reduction (MOR) approach for creating fast-running, nonlinear, multiphysics models in Verilog-A. This new approach differs from previous work by creating the reduced order model (ROM) directly from an accurate, nonlinear, multi-physics representation. The mechanical and electrical nonlinearities of the MEMS structure are persevered to capture effects such as quadrature, amplitude-dependent frequency shifting and electrostatic softening. The reduction algorithm has been implemented in the commercial MEMS/IC co-design tool MEMS+. The approach's effectiveness is validated for a state-of-the-art, three-axis, capacitive gyroscope from Murata Electronics by comparing simulations of the created Verilog-A model with experimental data.

This paper proposes a framework for system-level modeling and simulation of a Micro Electro-Mechanical System (MEMS). We show how a reduced-order model of MEMS can be integrated into SystemC-AMS. We propose the use of an external linear algebra library and alternative time integration method. Both are used to customize a Timed Data Flow (TDF) module to address MEMS modeling. Experiments are conducted on a biaxial accelerometer to verify its response to a ramp impulse. Our implementation runs about twice as fast as the state space resolution currently implemented in SystemC-AMS 2.0. Results highlight potential improvements of SystemC-AMS standard to correctly simulate the analog behavior of MEMS devices.

Each new embedded system tends to integrate more sensors with tight software-driven control, digitally assisted analog circuits, and heterogeneous structure. A more responsive simulation environment is needed to support the co-design and verification of such complex architectures including all its digital hardware/software and analog/multi-physical aspects using Multi-Disciplinary Virtual Prototyping (MDVP). Taking a Micro-Electro-Mechanical System (MEMS) vibration sensor as an example, we introduce a reusable framework based on the state-of-the-art technologies SystemC AMS, Finite Elements/Reduced-Order modeling, and UVM to design, simulate, and verify such systems in their real application context.

Micro Electro-Mechanical Systems (MEMS) have been developed for years and find a wide range of applications. Nevertheless, there is still a lack of efficient collaboration between expert teams involved in MEMS design to enable an efficient multidisciplinary approach. Furthermore, the shrinking of the systems’ size and their growing integration level require to design HW and SW subsystems in a more parallel and integrated way. This work is focused on improving the MEMS design methodology and its integration into the overall HW/SW system design flow by using SystemC AMS extensions. A novel method for system-level modeling of MEMS in SystemC-AMS is proposed. Based on Reduced-Order Modeling, it intends to meet the system-level requirements for an efficient simulation in terms of speed, accuracy, and configurability.

SUMMARYWe are interested in the numerical approximation of steady scalar convection–diffusion problems by means of high order schemes called Residual Distribution schemes. In the inviscid case, one can develop nonlinear Residual Distribution schemes that are nonoscillatory, even in the case of very strong discontinuities, while having the most possible compact stencil, on hybrid unstructured meshes. This paper proposes and compare extensions of these schemes for the convection–diffusion problem. This methodology, in particular in terms of accuracy, is evaluated on problem with exact solutions. Its nonoscillatory behavior is tested against the Smith and Hutton problem. Copyright © 2012 John Wiley & Sons, Ltd.

We are interested in developing a numerical framework well suited for advection–diffusion problems when the advection part is dominant. In that case, given Dirichlet type boundary condition, it is well known that a boundary layer develops. To resolve correctly this layer, standard methods consist in increasing the mesh resolution and possibly increasing the formal accuracy of the numerical method. In this paper, we follow another path: we do not seek to increase the formal accuracy of the scheme but, by a careful choice of finite element, to lower the mesh resolution in the layer. Indeed the finite element representation we choose is locally the sum of a standard one plus an enrichment. This paper proposes such a method and with several numerical examples, we show the potential of this approach. In particular, we show that the method is not very sensitive to the choice of the enrichment and develop an adaptive algorithm to automatically choose the enrichment functions.Copyright © 2012 John Wiley & Sons, Ltd.

We are interested in advection-diffusion problems with high Peclet number when shock like structure in the domain and strong boundary-layers both exist. This boundary-layer, though very thin, concentrates most degrees of freedom to get acceptable accuracy. We aim at designing a numerical framework able to reduce dramaticaly their number in the boundary-layer. This is done via a stabilized enriched finite elements method with Lagrange multipliers to enforce boundary conditions.