See you later, simulator?

Once upon a time, a recent mechanical engineering graduate decided to improve operation of the power plant where he worked. Using simulation software, the ME devised improvements that, as he proudly pointed out to his supervisor, would increase thermal efficiency to over 99%.

"That's fine," replied the crusty old supervisor, "but at 10 degrees Fahrenheit, that recirculated water is going to be mighty rough on the feed pump."

(Electrical engineers can be similarly and disastrously dazzled by simulation.)

Didja hear the one about the EE who didn't know about bypass capacitors leading to a product crisis requiring a major printed circuit board redesign? The board's developer, a newly graduated EE, used circuit-simulation software to perfect the microprocessor, memory, I/O, and glue logic, but he neglected to add any bypass capacitors to his board. My friend, who witnessed this episode, wonders whether the newbie engineer assumed that a technician would take care of those messy analog-related details that the digital simulator ignored.

In kinder, gentler, and more prosperous times, employers offered newly graduated EEs hands-on practical experience via apprenticeships or deliberate rotations through several departments. Today, employers want cheap labor in the form of new grads already knowledgeable in a particular specialty who can hit the ground running.

In college, software simulators offer students quick exploration of complex designs. Inexpensive student-grade simulators, however, can't easily cope with design elements that aren't supposed to be present (such as power plane inductance and capacitance, or intercircuit stray coupling). Worse yet, curricula that rely heavily on simulation software may offer little or no hands-on exposure to practical electronics. Students won't know what they're missing.

Although today's jam-packed EE curriculum won't make it easy, educators could make the presentation of a suitably complex, functional, and physical analog and digital project a prerequisite for graduation.

Why should test engineers worry about over-reliance on circuit simulation and the disappearance of hands-on electronics? Because we have to cope with, and guarantee performance of, half-baked products that may only "sort of" work. Besides, would you want your appendix removed by a simulator-trained surgeon holding a scalpel for the first time?

Brad Thompson, Contributing Technical Editor, brad@tmworld.com