Once you’ve got an idea, how long does it take to turn that idea into
a product? That depends on a large number of factors, including the developer’s
expertise. Starting from scratch is always an option. Alternatively, building
on a broader base can shorten delivery schedules, increase functionality, and
possibly reduce end-product costs. Enter the reference design.
Vendors deliver reference designs to highlight their chips, modules, software,
or services. But not all reference designs are created equal. At one end of
the spectrum are complete, full-function designs with which designers typically
extend or customize the solution. At the other end, the reference design becomes
a platform. It highlights one or more features in a way that’s often
easy to incorporate in another design.
FULLY FUNCTIONAL
Often, the completeness of a reference design is based on the target audience.
Say you’re talking lap-tops. The changes to a reference design may only
be the color and texture of the case. For example, VIA Technologies’
lightweight (1.87 lb) Nanobook UMD (ultra-mobile device) highlights the company’s
VIA processor and chip set (Fig. 1).
It was developed in conjunction with First International Computer.
Richard Brown, VP of corporate marketing for VIA Technologies, notes that this
type of platform is often called “ready for market.” Developers
can make minor changes to the case or more major enhancements, such as adding
a Voice over Internet Protocol (VoIP) module. VIA will address the specific
needs of its customers, or the customers may take the design and implement or
enhance it.
With such an approach, customers can exploit the vendor’s expertise
for components like the 1.2-GHz VIA C7-M ULV processor or high-speed interfaces.
And, reference designs can be brought to the market rapidly at a minimal cost.
Sometimes, though, it’s not a matter of the difficulty of implementation.
Instead, it’s a matter of taking advantage of a new idea. Many fully
functional reference designs will need to be customized after they hit the market.
Developers interested in using Future Technology Devices International’s
Vinculum VNC1L chip might want to start with DLP Design’s DLP-VLOG (Fig.
2). This sensor recording system works with a standard USB flash memory
stick. The board contains a Microchip PIC16F88 plus a temperature and humidity
sensor, a real-time clock, and two analog input channels for measuring voltages
in the 0- to 30-V range.
The DLP-VLOG can be used in many applications as is, but it also is customizable
since it’s a reference design. Developers can easily take the layout
and change the kind of interfaces being polled with minimal alterations. And
while reference designs presented by vendors may be as complete as these examples,
they target customers who likely will make more significant changes to the design.
Advanced Micro Devices created its ETX Reference Design Kits (RDK) in conjunction
with Logic Product Design (see “x86 System-On-Module Cuts Time-To-Market”
at www.electronicdesign. com, ED Online 12443). The kits high-light
AMD’s Geode processor chip, using a system-on-module containing the Geode.
When using this approach, the module can be incorporated in a final design.
The complete schematics and support documentation are available, so a great
deal of the system design work is already done. However, the reference design
would still need significant enhancement for any product. Unlike the more complete
reference designs examined earlier, these systems don’t target a specific
application. These more general reference designs border on developments that
are even further from a complete product.
DEVELOPMENT KITS
I’ve been doing hands-on reviews of development kits for a number of
years now (see “The Launch Of A New Web-Exclusive Department,”
ED Online ID 8270). Over that time, I’ve seen significant improvements
in both the sophistication of the platforms and the depth of support, especially
on the software and tools sides.
In many cases, hardware designers augment the reference designs or development
kits. But significant development often occurs before the custom platform is
available. This is particularly relevant for module-based solutions like COM
Express.