In my prior two post (Part I and Part II) on designing industrial strength systems I discussed thermal management issues and various methods for hardening designs against EMI and ESD. In the last installment I discussed system failures due to lightning effects and other electromagnetic susceptibility issues. These failures can be subtle and only slightly damage a device affecting its long term reliability or they can be catastrophic leaving nothing but charred lead-frames where the components previously resided. However, there is another potential problem hidden within many industrialized systems that can lead to lost revenue and disappointed customers… it is obsolescence.
Many engineers never consider component longevity when selecting devices for a design. In our world of consumer products, new models replace their predecessors in less time than it takes to make a human being (9 months). However, industrial systems may stay in production (unchanged) for 10 to 20 years due to regulation and certification. For instance, fire alarm systems must pass an extensive set of qualifications before they can be certified to be installed into a structure. This is to insure the proper operation in severe conditions where life safety is involved. Any change to the system such as a redesign to replace an obsolete component requires recertification to some degree. This can be an extremely costly and time consuming event – one that is avoided at all cost. However, if a critical component is no longer available, the system will need to be redesigned.
Texas Instruments has understood this problem for many years and has an extremely deep portfolio of devices with very long life-spans. There are components still available that are tens of years old, but still in production and probably will be for many more. TI’s obsolescence policy is one of the best in our industry and provides engineers with the peace of mind that a component will not disappear in 6 months.
To really make sure your design can remain unchanged for the foreseeable future, TI also provides a program called “Enhanced Products” or EP. This program not only has enhanced obsolescence management which provides a much longer supply term for devices, it provides another level of screening to ensure the highest industrial standards – plus, the EP up-screening doesn’t void a device’s warrantee – something to consider when using third-party screening houses.
So I hope you have enjoyed my little series on Industrial Strength Design. For more information see our industrial application page on TI’s website. Also, be sure to tune into the “Ask the Expert” between June 17th and the 28th to submit your communications and data transmission questions to yours truly. I welcome your comments and hope to hear from you! Till next time…