|
Small and Mighty: Signal and
Power Connector Performance
By Russell Paik, Worldwide
Director of Product Management,
ITT Interconnect Solutions
Demand for smaller and more
versatile components continues
across many applications as the
demand for smaller form factors
continues to grow. Customers
want portable and handheld
electronic components to have
low profiles and occupy minimal
board real estate in order to
make end products thinner,
smaller, and lighter. In
addition to size specifications,
advanced connectors must also
meet durability requirements in
terms of ruggedness and life
cycle counts.
Bringing
Down Size and Cost
Portable electronics
applications, including cell
phones, GPS units, and gaming
devices, require a variety of
connectors to satisfy various
functions within the devices.
Solderless components, including
microphones, grounding clips,
and antennas, all require
specialized connector solutions
to achieve various functions.
This often results in the need
to qualify several
non-standardized connectors with
uneven spring forces and poor
contact resistance.
One solution is to bring the
solderless components down to
the motherboard using a single
contact that reduces component
count, minimizes contact
resistance, enhances
functionality, and increases
reliability. For example, ITT
Interconnect Solutions’
Universal Contact mechanism
features a board-mounted profile
as low as 0.8mm, and has the
ability to be placed across the
axis to bring the component down
to the board. In addition, the
design engineer only needs to
qualify one connector or
contact, as the same connector
is used across the platform. The
Universal Contact is made using
a unique side stamping and
forming that creates “wings”
with cross-beam tabs to provide
a pre-load force high enough to
keep a point of contact on the
mating surface (approximately
300k psi). If the contact is
only deflected by 0.1mm, 0.3
Newtons of force is seen,
significantly adding to the
reliability of the design.
Packaging Performance and
Reliability
The role interconnect
devices play in providing
protection from voltage spikes
to internal systems is
imperative. Today’s portable and
handheld devices require highly
reliable, rugged, and
lightweight filter connectors.
Typically, filter connectors use
ceramic planar arrays for
filtering, but they don’t stand
up well to repeated shock,
vibration, and thermal extremes.
Today’s planar array designs use
ceramic block capacitors with
plated thru-holes where
feed-thru contacts are inserted
and soldered into place,
requiring costly thermal shock
screening and burn-in procedures
for quality assurance.
As an alternative solution,
fragile ceramic planar array
block capacitors can be replaced
with state-of-the-art flexible
circuits, where individual chip
capacitors are surface-mounted
on a pad adjacent to the
feed-thru contact.
Adapting to the chip-on-flex (CoF)
technology for use in filter
connectors provides a
significant performance
improvement in thermal shock and
vibration. New CoF designs
feature feed-thru contacts that
are not soldered directly to the
capacitor, thus virtually
eliminating thermal stress
points that impact thermal shock
and vibration performance.
These CoF filter connectors
provide all of the standard
filtering capabilities,
including individual isolated
pin filtering of high-frequency
noise, built-in ground plane
barriers in the connector
inserts, and filtering at the
face of system boxes. The
connector provides a stray
signal barrier upstream and away
from electronic devices to
protect critical circuits from
electrical interference without
affecting system function and
performance. The result is a
robust filter connector with
superior mechanical performance
and improved reliability. In
addition, the chip-on-flex
connectors are significantly
lighter because less solder is
required for the flex material,
providing a weight reduction of
up to 15%.
The CoF filter offers the system
designer complete flexibility in
defining or changing individual
circuit capacitance, and ground
and electro-magnetic pulse (EMP)
performance during the
design/development phase, and
eliminates the need to retool
the ceramic planar array. The
CoF design employs readily
available flex circuits and
devices, leading to reduce
design/development cycle time
and faster production delivery.
CoF technology not only
maintains the same performance
benefit as traditional ceramic
filter capacitors, but it
affords customization for the
end users.
CoF technology provides filter
connectors with built-in ground
barriers in the connector
insert, which eliminates
electromagnetic interference
(EMI) windows in systems where
connectors enter or exit boxes.
CoF technology also offers
filtering at the face of system
boxes, thus eliminating
filtering on the PCB, freeing up
board space and maintaining EMI
integrity of the system by not
allowing unwanted signals to
enter the box.
At the rate portable electronics
technology is advancing, it is
critical for manufacturers to
consistently develop innovative
technology to meet new demands.
Miniaturization, weight
reduction, cost specifications,
increased functionality,
performance, and reliability are
critical factors. Advanced
filter connector technology
provides reduced packaging size,
and represents a less
labor-intensive and more
cost-effective total solution.
Visit
ITT Interconnect online.
|
|
