October 2016 • The PCB Design Magazine 57
• Optimization of the PDN is a trial-and-
error process that needs to be done in
conjunction with the stackup materials to
fully exploit all avenues.
PCBDESIGN
References:
1. Barry Olney's Beyond Design columns:
Intro to Board-Level Simulation and the PCB
Design Process, Impedance Matching: Termina-
tions, Learning the Curve, PDN Planning and
Capacitor Selection, Part 1 & 2, Master "Black
Magic" with Howard Johnson's Seminars.
2. Art and Engineering in Product Design,
by Andrew Taylor.
Barry Olney is managing director
of In-Circuit Design Pty Ltd (ICD)
Australia. The company is a PCB
design service bureau that special-
izes in board-level simulation. ICD
has developed the ICD Stackup
Planner and ICD PDN Planner soft-
ware, which is available here. To contact Barry,
click here.
DARPA's Microsystems Tech-
nology Office (MTO) has a proud
history of making seminal invest-
ments in breakthrough technolo-
gies that ultimately became critical
components in our electronics-
filled world, from flash memory to
radio frequency (RF) semiconduc-
tors to microelectromechanical
systems (MEMS). But DARPA does not develop tech-
nologies on its own. The Agency's approach is to set
extremely challenging goals and then offer innova-
tors at universities and companies the support they
need to pursue those remote but exciting frontiers.
MTO's commitment to that catalytic role—and
the opportunity to engage with DARPA on the next
generation of cutting-edge advances—is now ex-
panding with the introduction of a simpler con-
tracting approach for companies and other entities
that have not previously worked with DARPA or had
large contracts with the Defense Department.
This new approach aims to help
the Agency and the nation take
fuller advantage of the enormous
depth and breadth of private-sector
creativity that is currently brewing
in the fast-evolving domains of net
-
worked sensors, spectrum access,
machine learning, and hardware
security. In particular, it aims to re-
duce barriers for innovative companies that don't
engage in the standard federal contracting process.
For example, DARPA recently worked with two
small companies on twin advances that could en-
able next-generation radio frequency (RF) arrays for
both military systems and commercial wireless com-
munications. The newly announced approach takes
advantage of DARPA's so-called Other Transactional
(OT) authority, which grants the Agency certain al-
ternatives to provisions in the standard Defense De-
partment contracting rules, known as the Federal
Acquisition Regulation, or FAR.
DARPA's Microsystems Technology Office Streamlines Contracting for Innovators
• The "bathtub curve" displays the typical
reliability of diverse products regardless of
their functionality.
• Premature failures are typically the result
of poor design practice or substandard
manufacture.
• The cost of development is dramatically
reduced if simulation is employed early in
the design cycle.
• Reference designs are arguably the cause
of many reliability issues.
• The key pillars of stability: Firstly, plan
the most efficient stackup configuration
for the design. Dielectric materials vary
in both dielectric constant and dissipa-
tion loss with frequency so the maximum
bandwidth is used.
• Secondly, impedance match the source
to the transmission lines. To do this, the
source impedance from the IBIS model of
the driver needs to be calculated.
• Finally, ensure that the power planes and
associated decoupling can handle the
high switching current demanded by the
processor and memory devices.
ROCK STEADY DESIGN
