Another vital part of the burden is the need for
detailed application expertise. “A reference design
has to be targeted to a specific application,” says
Valentino, “and we have to be particularly versed in
what the end performance requirements of our design
must be.”
Companies may also work with third parties to
augment their reference design efforts. “Sometimes
you have to go out and get expertise,” says Valentino,
“in order to address a market in a hurry because you
have a short market window.”
Semiconductor companies have developed a variety
of strategies to cope with these burdens. One
is to focus their efforts only on key markets and
components. STMicroelectronics, for instance, has
more than 16,000 active part numbers, but only offers
about 200 ready-to-go reference designs.
“We attack only those market segments where the
added value of our product mix is a major advantage,”
says Aleo. The company also multiplies its
exposure by incorporating as many STMicro products
in a single reference design as possible—from
six to 15 on each board, according to Aleo.
Another approach is to create multiple reference
designs addressing different needs. QuickFilter starts
by creating a generic design that it can then leverage
to create a series of application-specific designs,
notes Valentino.
Freescale sees a need for both educational and
production-ready reference designs. “Full designs get
customers to market quickly when they don’t have
expertise,” says Neidig. “But for more established
applications, customers have developed their expertise
so they don’t need full production readiness.”
Regardless of the type of reference design that’s
offered by a semiconductor vendor, developers
should ensure that it has full software. “Software
is a key aspect when evaluating reference designs,”
says Lowe. “How much of a whole solution is the
vendor providing?”
Developers should also check to make sure the
reference design’s software is available for use. “We
keep reminding our customers that they will need to
get a license to use some of the software we include
in the reference design,” says Neidig.
Finally, designers need to make sure the documentation
for the reference design includes the education
aspect, even when they’re adopting the design wholesale.
“The reference design is not useful without
documentation,” says Prakash. “It saves questions
at the end.”
Documentation should include information on
how to make changes, what to change, and warnings
of what not to change—like high-speed circuit
layouts—as well as the full details on how to fabricate
the design.