Hands Up, Anyone Believe That Toyota's Problems Are All Physical?

In the past number of weeks/months we have all seen how Toyota has struggled to manage perception around their "sudden acceleration" problems. The first fix that was proposed was a replacement of the floor mats, under the argument that the mats had been forcing the gas pedal down. Quickly following this first "solution", Toyota announced that they were issuing a recall to fix the mechanics of the gas pedal, adding a small spacer to prevent the pedal from getting physically stuck.

Even during the recall, there started to appear a number of people who were stating that their pedal wasn't physically stuck, and that they were unable to turn off the engine or shift the car into neutral. The implication is that while the physical fixes may have helped, there might be a more underlying problem associated with the electronics.

There are some good reference pages online (example report from Frost & Sullivan) that show how the automotive industry is expanding its use of integrated electronics.

As far back as 2003, BMW announced that their 5- and 7-series cars already had upwards of 100 microprocessors in them, to manage functions from engine control to opening the windows, and unless designed very carefully, these systems could fail a number of different ways. One failure mechanism is the software itself getting locked in a tight loop ... who hasn't had to force a reboot on their computer to get it out of such a situation? Another failure mechanism could come from some form of electrical interference, either in the wiring harnesses or directly in the microprocessor and sensor chips.

With safety as their #1 goal, automotive suppliers must perform rigorous testing and validation to prove that their components are not going to fail under some harsh conditions, including large operating temperature ranges, high levels of humidity, varying voltages, electro-magnetic interferences, mechanical stress ... the list is long.

Specifically for the chips that are used in automotive systems, there is an absolute requirement that they are validated to correctly operate under all possible conditions and scenarios. What does this mean to the automotive chip design team? Many weeks of simulations to ensure that the functionality is operating correctly in all possible modes of operation, extended physical verifications to ensure that the chips do not fail due to the high stress environments that they execute in, and extended electrical checking to ensure that timing, IR drop, electromigration, Joule heating, electro-static discharge, latch-up, signal integrity and ... and ... and ..., are all fully validated.

EDA is a critical component of design, and so we must ensure that EDA tools and functionality used to perform such comprehensive verifications and validations continue to keep up with the ever-advancing chip design requirements and the ever-increasing focus on safety.

If you are interested in a similar viewpoint of the challenges of the automotive industry, you might want to take a look at the blog from Richard Goering on the Toyota Prius.

Is there anyone from the automotive design industry that would like to give us the views from the design team?

Pete McCrorie