( ESNUG 309 Item 8 ) ---------------------------------------------- [1/27/99]
From: "Shankar Hemmady" <hemmady@gurutech.com>
Subject: ( ESNUG 300 #3 ) The Politics Of Testing, Tools & Test Engineers
John,
In ESNUG 300 #3 (titled "Some Honest Comments On The Current State Of The
Test World"), I wrote a technical revue of many variety of test tools
and techniques. I'd like to follow up by explaining the politics of
testing, tools, and test engineers.
In the area of VLSI manufacturing testing, the praise clearly has to go to
the EDA companies. In spite of the sheer lack of interest and in many
cases, utter disgust, of the manufacturing test area from design engineers,
the EDA companies have done a reasonably good job of creating decent tools
and solutions for defect measurement and defect coverage.
There are many good reasons why a typical chip or system design company can
not and need not be interested in chip testing, fault simulation and other
related activities, such as:
* For products with a short life cycle, getting a lion's share of the
market is far more critical than getting the best test coverage.
* Test coverage usually does not play an important role in getting
samples out to customers, unless your customer really needs the
quality. In applications like space exploration, medical diagnostics,
mil-aero systems, autos, telephony, financial systems etc., getting
a reliable, fault-tolerant system is crucial. A hierarchical
manufacturing test approach may reduce and alleviate some of the
problems we see in real life. However, even in such cases, most often
the major disasters are traceable to "bugs" in the system or chips or
software, rather than to manufacturing related defects.
* In general, area (cost), timing (speed) and power will always be higher
priorities over testability and high coverage. I may not make many of
my DFT/ATPG colleagues happy by saying that. But that's the reality.
That's also the reason why many of my (potential) customers call me for
ATPG/Faultsim/DFT related work at the very last minute. The other
issues cannot be compromised. Unless volume production is at stake, and
defect rate is a major concern, manufacturing testing is compromisable
and is quite often compromised.
With all the above good reasons, it is no surprise that test automation
tools have always been undersold, under-utilized and have been considered
unnecessary by most companies except the leading-edge, quality conscious
companies, and companies that have been in areas that I have mentioned
above where the liabilities can be substantial.
So how has the EDA industry responded to such a low level of interest from
customers? Like most insurance policies, manufacturing test tools have sold
very well after disaster strikes. Without quoting any specific instances,
it should suffice to say that most companies have used EDA tools for test
only after they were desperately arm-twisted by their potential or current
customers for lack of quality, lack of relaibilty, terrible defect rates,
etc...
- Shankar Hemmady
Guru Technologies Cupertino, CA
|
|
