New online training course for AXIEM EM Simulator in AWR Microwave Office is available.(read more)

Introduction

Multiphysics is an integral part of the concepts around digital twins. In this post, I want to discuss the mechanical aspects of multiphysics in system simulations, which are critical for 3D-IC, multi-die, and chiplet design.

The physical world in which we live is growing ever more electrified. Think of the transformation that the cell phone has brought into our lives, as has the present-day migration to electronic vehicles (EVs). These products are not only feats of electronic engineering but of mechanical as well, as the electronics find themselves in new and novel forms such as foldable phones and flying cars (eVOTLs). Here, engineering domains must co-exist and collaborate to bring about the best end products possible.

Start with the electronics—chips, chiplets, IC packaging, PCB, and modules. But now put these into a new form factor that can be dropped or submerged in water or accelerated along a highway. What about drop testing, aerodynamics, and aeroacoustics? These largely computational fluid dynamics (CFD) and/or mechanical multiphysics phenomena must also be accounted for. And then how does the drop testing impact the electrical performance? The world of electronics and its vast array of end products is pushing us beyond pure electrical engineering to be more broadly minded and develop not only heterogeneous products but heterogeneous engineering teams as well.

Cadence's Unique Expertise

It's at this crossroad of complexity and electronic proliferation that Cadence shines. Let's take, for example, the latest push for higher-performing high-bandwidth memory (HBM) devices and AI data center expansion. These technologies are growing from several layers to 12, and I can't emphasize enough the importance of teamwork and integrated solutions in tackling the challenges of advanced packaging technologies and how collaboration is shaping the future of semiconductor innovation and paving the way for cutting-edge developments in the industry.

These layered electronics are powered, and power creates heat. Heat needs to be understood, and thus, the thermal integrity issues uncovered along the way must be addressed. However, electronic thermal issues are just the first domino in a chain of interdependencies. What about the thermal stress and warpage that can be caused by the powering of these stacked devices? How does that then lend to mechanical stress and even material fatigue as the temperature cycles from high to low and back through the use of the electronic device? This is just one example in a long list of many...

Cadence Multiphysics Analysis Offerings

The confluence of electrical, mechanical, and CFD is exactly why Cadence expanded into multiphysics at a significant rate starting in 2019 with the announcement of the Clarity 3D Solver and Celsius Thermal Solver products for electromagnetic (EM) and thermal multiphysics system simulations. Recent acquisitions of Numeca, Pointwise, and Cascade (now branded within Cadence as the Fidelity CFD Platform) as well as Future Facilities (now the Cadence Reality Digital Twin product line) are all adding CFD expertise. The recent addition of Beta CAE brings mechanical multiphysics to the suite of solutions available from Cadence. The full breadth of these multiphysics system analyses, spanning EM, thermal, signal integrity/power integrity (SI/PI), CFD, and now mechanical, creates a platform for digital twinning across a wide array of applications. You can learn more by viewing Cadence's Reality Digital Twin platform launch on the keynote stage at NVIDIA's GTC in March, as well as this Designed with Cadence video: NV5, NVIDIA, and Cadence Collaboration Optimizes Data Centers.

Conclusion

Ever more sophisticated electronic designs are in demand to fulfill the needs of tomorrow's technologies, driving a convergence of electrical and mechanical aspects of multiphysics in system simulations. To successfully produce the exciting new products of the future, both domains must be able to collaborate effectively and efficiently. Cadence is fully committed to developing and providing our customers with the software products they need to enable this electrical/mechanical evolution. From EM, to thermal, to SI/PI, CFD, and mechanical, Cadence is enabling digital twinning across a wide array of applications that are forging pathways to the future.

For more information on Cadence's multiphysics system analysis offerings, visit our webpage and download our brochure.

Hi everyone,

I'm currently working on my thesis, which involves a beamformer system using CMOS 65nm technology. I'm trying to use the EMX tool for EM simulation but have encountered a few problems. Before diving into my questions about EMX, let me briefly explain how I conduct EM simulations with other software (ADS).

In ADS, I use the EM simulator with the Momentum microwave engine. However, my EM layout is quite large, and the mesh generated is extremely detailed, making it difficult to simulate the entire system. As a workaround, I divide the system into smaller parts and simulate each one individually. I've attached a snapshot of my setup, which includes an amplifier and a 1-to-2 Wilkinson power divider. I've separated these circuits and placed pins to facilitate EM simulations for each. I also placed ground pins at the boundaries of each circuit to connect them to the ground plane.

Here’s the link to the image (I'm unable to upload it due to an error): https://drive.google.com/file/d/13Qn4-DvMBj_K1JQLXrTWaWZ8uaLJr15u/view?usp=sharing

Now, moving on to EMX (version 6.3). For a maximum frequency of 31 GHz, I set the edge mesh = thickness = 0.4 µm (approximately the skin depth). However, when I simulate the circuit (amplifier + divider), the mesh on the ground plane becomes very dense, which makes running the simulation impossible due to excessive memory requirements. I reverted to my ADS approach and divided the circuit into two parts, placing ports to connect them. Unfortunately, EMX doesn't allow me to place multiple edge ports on the same edge for the ground plane, which has left me confused. Here are a couple of questions I have:

1. Is breaking the circuit into smaller parts a valid approach? Given the large ground plane, the mesh size for the ground is significant, making simulations challenging. Are there any methods to manage this issue?

2. Regarding the ground pins, why can't I place multiple edge ports to connect the ground planes of both circuits as I did in ADS? If this approach is incorrect, could you suggest alternative methods for simulating individual circuits and connecting them to estimate system performance?

Any insights would be greatly appreciated. Thank you in advance for your help!

According to one aspect, an apparatus for computing a solution to a power flow problem for an electrical power system comprising a plurality of buses. The apparatus includes (a) at least one processor comprising a plurality of cores; and (b) memory coupled to the at least one processor for storing an admittance matrix for the power system, real power and reactive power for each bus, and an initial complex voltage for each bus; (c) wherein the at least one processor is configured to: (i) perform a Jacobi power flow calculation for each bus to determine the complex voltage for each bus, the Jacobi power flow calculation using the admittance matrix, the real power and reactive power for each bus, and the initial complex voltage for each bus as inputs, wherein at least two Jacobi power flow calculations are performed concurrently on the plurality of cores; (ii) calculate a power mismatch at each bus based on the complex voltages; and (iii) determine whether the Jacobi power flow calculations have converged based on the power mismatch and repeat (i) to (iii) if the Jacobi power flow calculations have not converged.

New York : Springer Science+Business Media, [2006]