Time for EDA to grow up Electronics News

The phrase Electronic Design Automation (EDA) was first coined to describe software that automated PCB layout and chip design. But the software has now evolved to such an extent that it’s hard to know what EDA really is anymore. The technology resembles a youth who’s reached the end of his formative years and is now looking for his true purpose in life.  

Companies such as Cadence, Synopsys and Mentor Graphics have defined the progression of EDA thus far, introducing evermore sophisticated software to allow design engineers to route, optimise and verify their electronics before a chip is placed or a solder joint made.

Today’s state-of-the-art systems allow digital designers to select modules from standard libraries of technology “cells” that they can build up to meet their project’s requirements. These cells are proven architecture, speeding design, improving yield and accelerating time-to-market. Analogue designers have it harder because it’s much more difficult to define “standard” components in that domain, but even here, things are moving ahead rapidly.

Altium has extending its software so every member of the design team can see exactly what’s happening across all design domains

Rob Irwin, Product Manager with Australian EDA vendor Altium, sums up the history nicely in his blog on the EEWeb portal. “If we hark back to the [early days of EDA], simply using the computer as a glorified drafting table didn’t really raise the abstraction level at which we could design,” notes Irwin.

“It just let us do what we’d always done, only a bit faster and more conveniently. It wasn’t until we used the computational power and logic available to automate processes and help make and enforce design decisions that we were able to move forward at the pace necessary to make the digital age a reality.”

So, job done then. Well, not quite, because today’s products aren’t just about laying out the electronics.

Inside the silo

Before EDA, chips and PCBs were routed by hand by taping out on sheets of acetate set up on light tables and then shrinking the resultant design by photographic techniques such that they could be used for manufacturing.

The first EDA programs automated this drafting procedure, but the real breakthrough came in the 80s with the introduction of the VLSI design philosophy. This methodology espoused the use of programming languages that the designer used to specify the performance he wanted from his chips and boards. The software then translated (or “compiled”) these instructions into the physical circuitry.

While undoubtedly improving electronics design efficiency, EDA has its drawbacks. For starters the software is complex, requiring a high level of expertise to operate, secondly it’s proprietary, meaning that it’s very difficult to swap from one vendor to another if disenchantment sets in, and third, attempts to integrate the electronics design with mechanical design and manufacturing have been patchy.

This last drawback has tended to reinforce a ‘silo mentality’ between the electronics design team and the mechanical and production engineers. There can even be divisions within the electronics design team itself between digital and analogue engineers, and hardware and software designers.

“This silo approach makes design tradeoffs extremely difficult,” says Mike Woodward, Communications Industry Marketing Manager with software modelling company The MathWorks.  “For example, the engineer may wish to use a cheaper power amplifier and correct for non-linearities using digital methods (for example, digital pre-distortion), something difficult to do with many design tools.

“Often, design tools are targeted at a single design domain (for example, analogue design) and don’t co-simulate well with tools for other design domains,” notes Woodward in an earlier article for Electronics News (see EN September 2010). “This makes interaction between engineering teams more difficult than it needs to be.”

Cadence has attempted to soothe the conflict between hardware and software engineers by introducing its System Development Suite. The company notes that the differentiator between modern electronic products is often the software.

“Conventional [design] flows require manual migration from hardware to software and from one development environment to another, which may take months,” the company notes on its website. “As a result, 50 percent of overall development time can be spent on system integration.”

“The System Development Suite … [enables a] seamless migration path through the design phases,” says Nimish Modi, Senior VP of the System Realization Group at Cadence. “This integrated flow … provides a significant breakthrough in addressing the challenges of early software development and hardware/software convergence, leading to a dramatic reduction in development schedules.”

Over the wall

But even when the electronics guys have got their act together, the end result could be “thrown over the wall” only to find that it bounces back weeks later because the packaged product runs too hot or a BGA can’t be reliably soldered.

In previous times a second iteration might have been possible, but with the pressure to produce ‘right-first-time’ designs to meet ever-shorter product cycles, those days are gone.

Some EDA vendors have reacted to customer pressure by attempting to add electro-mechanical and mechanical ‘modules’ to their products such that the electronics designers can take into account some of the challenges their colleagues will face further down the design chain.

Mentor Graphics’ Flomerics software allows the electronics designer to check the thermal performance of his design

Mentor Graphics, for example, acquired U.K. company Flomerics in October 2008. The computational fluid dynamics analysis company now forms the core of Mentor’s Mechanical Analysis Division. While Flomerics products can be turned to all forms of fluid flow, the primary advantage for Mentor is thermal analysis of electronics assemblies.

“Thermal analysis of today’s high powered, compact electronic products requires ever increasing sophisticated conduction and convection thermal analysis, for both the full enclosure and PCBs, during the design process to meet reliability and time-to-market goals,” said Henry Potts, a VP with Mentor, in a statement.

“As a supplier of design automation software, we must consider the entire product development process and provide analysis and collaboration tools wherever we can help our customers be more competitive.”

Altium’s Altium Designer product takes a similar approach with what the company describes as a “single, unified data model that lets every designer on a team see exactly what’s happening across all design domains – hardware, software and programmable hardware”.

“Productivity in electronics design is so much more than the speed to layout, reducing the numbers of prototypes, or the management of output files for manufacture,” noted Gerry Gaffney, regional CEO for the Americas at Altium, in a statement.

“All these design authoring features are, of course essential. But why create any type of prototype if you’re not sure whether it can be manufactured? Why know that a prototype board will fit its enclosure only to discover later that a changed component means that, suddenly, the production board does not?” asks Gaffney.

The top-down approach

EDA software has grown up in parallel with the electronics industry. That’s made it excellent for designing chips and boards, and latterly the software to drive those chips, but not so good at extending the design process beyond the electronics.

But electronics is rapidly moving beyond “electronic” products such as computers, TVs and mobile phones to become embedded into trains, planes, automobiles and, well, just about any modern product you can think of. And those products in turn are designed by software.

CAD/CAE companies could be looking to encompass electronics design in their software suites. (Courtesy: Autodesk)

As electronics has become more persuasive, the Computer Aided Design/Computer Aided Engineering (CAD/CAE) vendors - that until now have been concerned with designing jet engines and washing machines - are beginning to consider how to cope with the inevitable electronics content of their next products. They have not made their move yet, but a middleman, in the form of software modelling companies such as The MathWorks and National Instruments (NI) are pioneering the way.

The MathWorks promotes a model-based design approach based on its MATLAB and Simulink products. Model-based design allows engineers to construct a graphical representation of their system. But this graphical representation is more than just a visual model; it’s a dynamic environment that can be exercised with inputs so that engineers can simulate what will happen under real life operating conditions.

Simulink software uses functional blocks that accurately mimic the precise electrical or mechanical behaviour of the device they represent. MATLAB software provides the control engineer with access to a library of algorithms to aid the control design process. Observing the effect on the plant model and making changes to the algorithms until the model’s behaviour meets the specification optimises the control design.

The final step is to compile the optimised control regimes into C code and port to an MCU to control, for example, an engine management unit.

“The plant model allows design engineers to develop control laws for the machine and try them out via simulation,” Bradley Horton, principal applications engineer with The MathWorks Australia, told Electronics News in an earlier interview (see EN January 2010).

“There is no need to build expensive prototype hardware in order to test the control strategy – by simulation, Simulink and MATLAB enables control system development and early design verification.”

NI’s LabVIEW, launched in 1986 and now in its tenth incarnation, is a graphical programming environment used by millions of engineers and scientists to develop sophisticated measurement, test, and control systems using intuitive graphical icons and wires that resemble a flowchart.

“When combined with modular hardware, LabVIEW is the centrepiece of the NI approach to graphical system design,” said the company in a statement, “which provides a unified platform for designing, prototyping and deploying applications with maximum efficiency.”

“By using LabVIEW, we decreased our system development time by one-third compared to the time we spent with traditional approaches,” says Glenn Larkin, engineer for the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory in the U.S.    

Systems engineering

Software modelling packages like MATLAB and LabVIEW aren’t capable of designing boards and chips but they do simplify the development of control regimes that can then be easily ported to microcontrollers. That puts the development of such regimes within the scope of engineers that aren’t expert in chip programming. And LabVIEW’s strength in the test arena allows for promising initiatives integrating design with test.

Such opportunities for seamless connections between design and manufacturing teams haven’t gone unnoticed by the EDA vendors.  

Mentor Graphics, for example, has worked to combine a product, SystemVision, with NI’s LabVIEW such that test engineers can develop test programs without waiting for physical prototypes.

“Mentor has long recognized the need to move test integration up in the design process,” said Darrell Teegarden, a Director with Mentor’s System Modeling Group in a statement. “[SystemVision] makes it easy to test the design implementation virtually. SVX provides a virtual prototype of the entire system, while LabVIEW implements test program development and execution.”

SystemVision enables the system designer to model systems and components with a virtual prototype and use simulation to perform analyses of electrical, mechanical and thermal sub-system. The process allows test bench development to be done in parallel with system development and prototyping, speeding time-to-market.

What next?

The EDA vendors have dominated electronics design from the mid-80s, but a systems-engineering approach to modern product design is putting their hegemony at risk. The traditional vendors are reacting by pushing their business model to encompass more of the design process, but progress is slow and fragmented.

OEMs no longer want to maintain separate departments with teams of electronic, mechanical and manufacturing engineers working in glorious isolation. That old-fashioned hierarchical approach to product design is too expensive, too slow and too prone to design re-runs.

What’s needed, nay demanded, is a combined engineering team working in seamless harmony. The manufacturers are demanding software that covers electronics chip and board design, mechanical packaging, verification, code development and compilation, and even modelling of the performance of the electronics in its target application.

It’s a big ask, but if an EDA vendor doesn’t grasp the nettle soon a software modelling company or CAD/CAE firm inevitably will. The result will be an early death for the pioneers of EDA rather than a blossoming from precocious youth into confident adulthood.

Time for EDA to grow up Electronics News