CAD/CAM Corner
Are You Designing for Testability?

< Previous   Image 2 of 2   

Cadence's Encounter family offers a complete test flow from concept to the silicon for ICs and SoCs.   (Source: Cadence)
Cadence's Encounter family offers a complete test flow from concept to the silicon for ICs and SoCs.
(Source: Cadence)

< Previous   Image 2 of 2   

Return to Article

View Comments: Oldest First|Newest First|Threaded View
<<  <  Page 2/2
User Rank
bobjengr   8/15/2013 6:13:13 PM

Excellent article.  The first thing I thought of when reading your post was the care needed when programming.  I learned to program using PASCAL--a teaching language.  My instructor was absolutely paranoid regarding students applying proper and copious notes to code so transparency could be obtained.   In his way of thinking, documentation was critical to understanding and remembering the "why" of lines and lines of code.  Your design for testability certainly falls along the very same lines.   I am completing a project right now in which sensor ports are located strictly for design confirmation and pre-pilot testing. I have no idea if we will use all of the ports but they are there.  For production, we will lessen the number but still provide ability for trouble- shooting and field service.  Again--excellent post and a good reminder that considerable time can be saved if proper planning, including DFT, is considered.   

William K.
User Rank
Re: Indeed
William K.   8/18/2013 7:21:45 PM
Poor quality solder can certainly bring about the failure of an electronic system, there is no question about that at all. And not just the Xbox. I repaired a Kenwood stereo amplifier that died completely because of poor solder in the power supply area. It is not just the fact of a bad alloy mix, sometimes the wave solder machine is just a bit off, or the solder had excessive scum, or the pre-fluxing was inadequate, or possibly the bare circuit boards had excesive oxidation on the surface. Or maybe the temperature was a bit too high. Lots of different things can lead to poor board soldering, and inadequate inspections won't see the failures, and if they pass initial testing they won't be fixed, they will fail in a few months, and be out of warranty, so why should they care?

Now about line conditioners? Is that power line conditioners or audio line conditioners. If you have a noisy power line a good inlin filter may be a lot of help, if it is installed in a manner that allows it to prevent the noise from passing through. And a good filter is much cheaper than one of those good line conditioners like the ones that5 SOLA makes. 

William K.
User Rank
Design for testing, or design to be repairable?
William K.   8/18/2013 7:31:39 PM
All of the systems that I have designed have been designed not only to be testable, but also to be repairable. That goes way beyond just putting an adequate number of accessable test points on the PCBs, it also includes designing a package so that it can be opened for servicing after the product is built. Those wonderful snap assemblies are not so very wonderful a few months later when the plastic parts have become less ductile and much more brittle. That is what is never mentioned in those "design for assembly" classes. I often add the claim that "our products are worth repairing, while other products are certaainly worth recycling." That imessage, that  our products will have a much longer lifetime because they are repairable does make some sales, especially when it is along side a long warranty period.

The article was good, and the points well made, but don't forget that there is more to many products than just a circuit board. And the rest of the product should be testable as well.

<<  <  Page 2/2
Partner Zone
More Blogs from CAD/CAM Corner
The Business Advantage Group recently released its 2014 Worldwide CAD Trends Survey, announcing both a prospective increase in the cloud-based CAD industry and the anticipated incorporation of 3D printing.
Easel was created with beginners in mind. It acts as sort of a gateway app that takes novices from project inception to actual milling in just five minutes.
Autodesk, a leader in 3D design solutions, announced earlier this month that it has completed its acquisition of Delcam, a leading supplier of CAD/CAM manufacturing software, in its efforts to expand the company’s manufacturing software capabilities.
3D Systems absorbs Xerox’s Solid Ink Engineering to further expand its 3D printer prowess.
Texas Instruments' Webench is vying to win the Golden Mousetrap Award in the Analysis & Calculation Software category, but it is up against some pretty tough competition from Mentor Graphics, COMSOL, and aPriori Inc.
Design News Webinar Series
3/27/2014 11:00 a.m. California / 2:00 p.m. New York / 7:00 p.m. London
2/27/2014 11:00 a.m. California / 2:00 p.m. New York / 7:00 p.m. London
12/18/2013 Available On Demand
11/20/2013 Available On Demand
Quick Poll
The Continuing Education Center offers engineers an entirely new way to get the education they need to formulate next-generation solutions.
Apr 21 - 25, Creating & Testing Your First RTOS Application Using MQX
SEMESTERS: 1  |  2  |  3  |  4  |  5

Focus on Fundamentals consists of 45-minute on-line classes that cover a host of technologies. You learn without leaving the comfort of your desk. All classes are taught by subject-matter experts and all are archived. So if you can't attend live, attend at your convenience.
Next Class: April 29 - Day 1
Sponsored by maxon precision motors
Learn More   |   Login   |   Archived Classes
Twitter Feed
Design News Twitter Feed
Like Us on Facebook

Sponsored Content

Technology Marketplace

Datasheets.com Parts Search

185 million searchable parts
(please enter a part number or hit search to begin)
Copyright © 2014 UBM Canon, A UBM company, All rights reserved. Privacy Policy | Terms of Service