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grey market is the way in which many
counterfeit products enter the supply
chain.
Distributors can help with the situation
of monitoring the supply situation and
provide advance warning of last-time
buys and of the signs that may indicate
that a manufacturer will want to suspend
production. Digi-Key, for example,
sends out obsolescence notifications to
customers for parts they have bought
previously to ensure they are updated
on supply status.
A last-time buy can introduce further
issues as some procurement policies
are designed to reject products with old
date codes. As the target product ages,
components bought on a last-time buy
will often have date codes that will be
too old to fit with this policy.
If a part has gone into its end-of-life
phase and the user has missed the last-
time-buy deadline, other options may
be available. Devices that experience
lower sales volume than other parts
within a family are more likely to face
the end of production more quickly. In
many cases it is possible to replace the
obsolete part with one that is a near-
match, often with minimal redesign. For
example, a replacement microcontroller
may have more onchip peripherals than
the original part but will, when it runs the
same software, demonstrate the same
behaviour. The technical department
within a distributor such as Digi-Key can
provide valuable advice on form and fit
compatibility for many parts.
The long-term answer to obsolescence
issues is to plan for the eventuality
and build procurement strategies
around components and families that
have supply guarantees. To try to
provide customers with long lifetime
requirements, some semiconductor
manufacturers will commit to longer
support cycles for a selected group
of their parts. For example, Intel sells
a range of PC-compatible processors
that are standard parts but, so that
they can be used in long life-cycle
industrial applications, has earmarked
some products as being supported and
sold for ten years or more from initial
production. This information provides
users with high confidence of supply
when they design the parts into their
systems.
Franchised distributors are vital sources
of information in the design phase by
indicating to users which parts are
supported under long life-cycle plans.
Digi-Key, for example, has extensive
experience of advising on the medium-
to long-term supply scenarios for the
components they provide. Customers
can provide a bill of materials and
experts will check the document for
parts that are at risk of going end-of-
life.
In some cases, it is impossible to
avoid using a part with a high risk of
obsolescence because it offers key
features not available in competing
parts. In those cases, franchised
distributors such as Digi-Key can set
up contracts in which, in exchange
for a commitment on the number of
components needed during a product’s
lifetime, they will arrange that number
to be made available and stocked
in the warehouse and released for
manufacture as needed like any other
device.
Changing the product-design strategy
to accommodate obsolescence is
another approach that users can adopt.
This strategy assumes that a number
of the parts in the original design are
likely to become obsolete during the
product’s life-cycle. It involves planning
component purchases such that they
can be replaced more easily by similar
parts and accommodate technology
insertions that may involve changes
in package type and device speed. By
designing products such that they can
take form and function compatible
replacements, it is possible to reduce
the risk of being subject to supply
problems caused by the obsolescence
of a single component.
For example, the use of programmable
solutions provides a way to future-proof
key elements of a design. Programmable
solutions are often designed in such a
way that they can provide a high degree
of assurance over form, fit and function
for replacement products. Even though
the manufacturers may retire older
parts in favour of those built on newer
processes, the same design will easily
move to the replacement parts, which
can often be obtained in packages
pin-compatible with the originals. The
design tools are built in such a way that
a design ported to a later, more capable
part will in most cases behave as it did
in the older product.
Similarly, choosing microprocessors
and microcontrollers that use industry-
standard
architectures
available
from multiple vendors can provide a
greater degree of protection against
obsolescence than a product line that
may be available from only a single
manufacturer. Although finding a direct
match for a microcontroller from another
supplier’s range may not be possible,
changes to the design and software may
be minimal as such parts often provide
similar features and peripherals. The
only change may be to device drivers
to ensure that the peripherals are
mapped to the correct areas of memory
for the application. Microcontrollers
with on-chip programmable logic and
analogue peripherals have proven to be
the answer in a number of cases when
fixed-function parts have disappeared
from the market.
Replacing a dedicated part with the
programmable solution involves greater
design and integration effort but, in an
industry prone to sudden obsolescence,
it provides an effective way of managing
the problem for key parts of the system.
Even with effective design strategies,
obsolescence remains an issue that faces
many users of electronics components.
But with the help of supply-chain
partners who can advise on potential
alternatives and keep customers
informed of trends in production, it is
possible for companies to stay on top of
the problem.
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