Fuzz Buttons®

Fuzz Buttons® are high performance proprietary trademarked contact pins available ONLY
from Custom Interconnects and manufactured ONLY in the USA
.  
Fuzz Buttons® offer superior value to other contact technologies such as Pogo Pins, Spring
Probes, Hyberboloid contacts or even soldering.  This becomes especially evident when
requirements such as low signal distortion, high frequency, low insertion force, planarity,
shock/vibration resistance, weight and/or extended life come into play.
Fuzz Buttons® are available in a wide variety of diameters and lengths, with diameters ranging
from .010" to .500" and lengths ranging from .030" to as long as .500".   
Most Fuzz Buttons® we manufacture are intended to address fine pitch contact requirements
primarily at the 1mm pitch level, but also can serve applications with as small as a .4mm pitch.  
Fuzz Buttons® can mate to virtually any packaging type used in the market today - including PGA,
BGA, LGA, CGA, QFN and MCM, as well as any custom packaging that a customer may be
employing.  This makes them ideal for use in PCB/PWB interposers, connectors, Test Sockets
and chip packaging.
We also manufacture many large format Fuzz Buttons® that can resemble cylinders, slugs,
discs, doughnuts and washers.  These are typically utilized for specialized EMI Shielding and/or
for compliant high current capable ground pads.  It is also possible to lay small or large Fuzz
Buttons® on their sides individually or in an end-to-end configuration to emulate a compliant
EMI "bead" or to make a long X-axis or Y-axis connection.

History
Fuzz Buttons® were first introduced to the electronics marketplace in 1959 and were mainly
used in grounding applications.  A later example includes their use as static dissipation pads
for IBM computer chassis in the 1980s.  Additional customers and applications began to
emerge as Fuzz Buttons® gained popularity in the marketas a highly flexible interconnect
design solution.  Soon the military sector took notice and began to utilize them in shock-
resistant PCB connectors for missile and satellites.  In the early 1990s, Fuzz Buttons® were
miniaturized to address the growing semiconductor test market.  Fuzz Button® test sockets
were highly regarded by customers such as Qualcomm, AMD and Texas Instruments, when low
signal distortion was especially important during development testing, but also for the high
mating cycles required for production testing.
Today Fuzz Buttons® still serve the military and commercial markets in many surprising
applications.  You will find them in weaponry, satellites, space probes, aircraft, test floors,
laboratories, radar arrays, antennas, supercomputers, crash test dummies, automotive
production, communications and even packaged inside high-end RF products such as
attenuators and amplifiers.  Because they are so versatile, Fuzz Buttons® can be used for DC,
UHF, L, C, X, Ku, Ka and Q Bands.

Making a Fuzz Button®
Fuzz Buttons® are a simple, yet elegant structure - whereby, the signal element and the spring
are one and the same.  There are no other moving parts that can cause failure or degrade
signal integrity, the Fuzz Button® is the direct mating point.
They are manufactured from a long strand of highly specialized very fine wire (often as fine as
human hair) that offers high levels of conductivity, strength and oxidation resistance.  There are
several wire material types available, most are Gold-plated, primarily for the properties of
conductivity and prevention of oxidation.  The most common wire materials used are either a
Gold-plated Beryllium Copper alloy (Au/BeCu) or a Gold-plated Molybdenum (Au/Mo).  While
Au/BeCu offers the lowest signal distortion levels and high mating cycle repeatability, Au/Mo is
utilized commonly also because of its high level of structural stability at temperature extremes.
Fuzz Buttons® are also available in specialty materials, such as Gold-plated Tungsten (Au/W),
Gold-plated Nickel Chromium (Au/NiCr) or non-magnetic Au/BeCu).  These are used in special
cases - such as operating states at extremely high current or temperature (Au/W or Au/NiCr) - or
when magnetic properties are of special concern.
Fuzz Buttons® are fashioned from these wires using a highly-guarded process that forms them
into individual units of certain diameter and length specs.  The manufacturing process causes
the wire to be randomized throughout the Fuzz Button® structure.
This randomization results in some very desirable effects, such as
  • Breaking up of internal induction fields that otherwise would form from a coiled spring
    configuration
  • Reduced signal path length and skin effect levels
  • Increasing the overall structural integrity and strength of the Fuzz Button®
  • Creating multiple points of contact within the Fuzz Button® itself, an internal "redundancy"

Fuzz Button® Specs
Applications: LGA, BGA, PGA, CGA, QFN and more
Pitch Capability: .4mm and above
Compliance/Travel: 15 - 30% of length / 20% nominal
Compression Force: 34 grams
Current Capability: 5 Amps Continuous
Operating Temperature: -60°C to 150°C
Typical Mating Cycles: Fuzz Buttons alone up to 5000 cycles/ with Hardhats up to 500,000 cycles
Frequency Capability: to 40 GHz in natural state, to 100 GHz with design optimization
Cross Talk/Bandwidth: -20dB@10Ghz
Insertion Loss S21: -1dB@26GHz
Return Loss S11: -20dB@10GHz
Inductance: 0.19nH Self / 0.03nH Mutual
Capacitance: 0.16pF Ground / 0.008pF Mutual
Resistance: <10mΩ
Rise/Fall TIme: 50ps / 50ps
Note: Representative values above are for .020" diameter/1mm Pitch, see Technical Data
page for more information on other configurations.

Contact Technology Comparison
Fuzz Buttons® ...Making Connections


Custom Interconnects, LLC
7790 E. Arapahoe Rd, Suite 250
Centennial, CO  80112
Phone: 303.934.6600
Fax: 303.934.6606
Email:
sales@custominterconnects.com
Click here for Fuzz Button Datasheet
For Fuzz Button® Datasheet,
please click on the picture below:
Applications: PCB Interposers, Device Interposers,
Production Sockets, Test Sockets, Connectors, RF / Coaxial
Interconnects, compliant grounding/shorting plates and
internal packaging grounds.
Large Format Fuzz Buttons®
Applications: Compliant grounding, specialized EMI
Shielding and as Static Dissipation Pads.
Fuzz Button® Part Numbering

WW-DDDLLL

WW = Wire Type
DDD = Diameter (in inches)
LLL = Length (in inches)

Example: 80-020130

Wire Types
80 = Au/BeCu (Gold-plated Beryllium Copper)
Most popular due to best S-parameters, lowest resistance

81 = Au/Mo (Gold-plated Molybdenum)
Excellent dimensional stability

82 = Au/W (Gold-plated Tungsten)
Higher temperature, premium cost, very stiff

83 = Au/NiCr (Gold-plated Nickel Chromium)
High temperature, low resistance, premium cost

Non-Magnetic Wire for Specialized Applications
Au/Mo for .010" and .015" Diameter Fuzz Buttons
Au/BeCu and Au/Mo for .020" to .062" Diameter Fuzz Buttons
         
*Contact Factory for Details*

Diameters
.010", .015", .020", .025", .030", .038", .045", .050", .062",
.075", .080", .090", .125", .150", .170", .200", .250", .280"
For custom diameters, please contact factory

Lengths
Available ranges shown for each diameter
.010" = .040" to .080"
.015" = .040" to .110"
.020" = .040" to .160"
.025" = .040" to .200"
.030" = .030" to .250"
.038" = .038" to .250"
.045" = .045" to .250"
.050" = .050" to .250"
.062" = .062" to .300"
.075" = .075" to .300"
.080" = .080" to .300"
.090" = .090" to .400"
.125" = .060" to .400"
.150" = .060" to .500"
.170" = .060" to .500"
.200" = .060" to .500"

.250" = .060" to .500"

.280" = .060" to .500"

Fill Rate
.010" and .015" diameters = 38%
.020" and greater diameters = 25%

Tolerances
Diameter +/-5% (exceptions are .010"/.015" dia)
Length +20/-0%
Fill +/-2%
For custom tolerances, please contact factory.
Fuzz Buttons are to be measured in the uncompressed
state and measured with digital calipers that capture the
main body structure of the Fuzz Button between the blades.  
Optical comparometers should not be used as they give
false readings due to the randomized wire forming
process.  What counts most is AFTER the Fuzz Button® has
been compressed during usage, whereby the amount of
material filling the holes remains very consistent across the
array.  Secondly, Fuzz Buttons® have a large range of
acceptable travel and compliance, they can solve many
stackup tolerance and board/packaging planarity issues.
80-020055 80-020070 80-062055 80-020040 80-020063 80-020118 80-063063 80-040200 80-020157 80-020200 80-010070 80-010040 80-055055
80-055260 80-015161 80-015200 80-020059 80-020102 81-020200 81-020118 80-020090 80-040098 80-030118 80-020078 80-020043 80-015110
80-040051 80-015080 81-020118 81-020200 weiliandk@163.com 18903792044
Floss Pin Luoyang Weilian Fuzz-Button http://www.fuzz-button.com/ fuzz-button.com fuzz-button spring element contact interconnect
80-015085 80-015090 80-015095 80-015100 80-015103 80-015110 80-015125 80-020020 80-020025 80-020030 80-020040 80-020040-CLT 80-020040-CLT5 80-020045 80-020045-CLT 80-020048 80-020050 80-020055 80-020056-CLT 80-020060
80-020100-CLT 80-020100-CLT2 80-020105 80-020106 80-020107 80-020110 80-020110-CLT 80-020110-CLT5 80-020112 80-020115 80-020116 80-020116-CLT5 80-020117 80-020118 80-020118-CLT 80-020118-CLT5 80-020120 80-020120-CLT
80-020120-CLT5 80-020124-CLT 80-020125 80-020130 80-020138 80-020140 80-020140-CLT 80-020145 80-020150 80-020160 80-020160-CLT 80-020160-CLT5 80-020161 80-020165 80-020167 80-020170 80-020170-CLT 80-020175 80-020180
30-01654 30-01766E-1 30-01767E-1 30-01768E-1 30-01803C-1 30-01804 30-01842B 30-02195A-1 30-20189 30-90300A 30-90383A 32-00277K
32-00534A 32-00813B-1 32-00927B 32-00929A 32-00956-1 32-00990 32-00994-1 32-01026 32-01034 32-01040 32-01044-1 32-01047-1 32-01736
32-01737 32-01738-1 32-01739 32-01740 32-01741 32-01744 32-01745 32-01746 32-01747 32-01748 32-01750 32-01751 32-10160 32-50005C-1
32-50015A 32-90080B-1 32-90151 32-90179 32-90203 32-90303G 33-00000 33-00002 33-00003 33-00005 33-00006 33-00007 33-00008 33-00010
33-00011 33-00013 33-00014 33-00015 33-00016 33-00017 33-00028 33-00037 33-00038 33-00043 33-00044 33-00045 33-00046 33-00047 33-00050
33-00051 33-00052 33-00053 33-00054 33-00055 33-00056 33-00057 33-00058 33-00059 33-00060 33-00061 33-00064-FB 33-00065-FB 33-00066
33-00069 33-00070-FB 33-00071 33-00072 33-00073 33-00074 33-00075 33-00076 33-00077 33-00080 33-00081 33-00082 33-00083 33-00085 33-00086
33-00087 33-00088 33-00089 33-00090 33-00091 33-00092 33-00093 33-00094 33-00095 33-00096 33-00097 33-00099 33-00100 33-00103 33-00104
33-00105 33-00106 33-00115 33-00116 33-00117 33-00118 33-00119 33-00120 33-00121 33-00122 33-00123 33-00124 33-00125 33-00126 33-00127
33-00129 33-00130 33-00131 33-00132 33-00133 33-00134 33-00135 33-00136 33-00138 33-00139 33-00140 33-00141 33-00142 33-00145 33-00146
33-00148 33-00149 33-00150 33-00151 33-00152 33-00153 33-00154 33-00155 33-00156 33-00157 33-00158 33-00159 33-00160 33-00163 33-00167
33-00170 33-00171 33-00173 33-00175 33-00176 33-00177 33-00200 33-00201 33-00202 33-00204 33-00206 33-00207 33-00208 33-00209 33-00215
33-00216 33-00218 33-00219 33-00220 33-00224 33-00225 33-00227 33-00228 33-00229 33-00230 33-00231 33-00232 33-00235 33- 0236 33-00237
33-00238 33-00300 33-00301 33-00303 33-00309 33-00312 33-00313 33-00314 33-00315 33-00316 33-00317 33-00320 33-00321 33-00322 33-00323
33-00324 33-00326 33-00327 33-00328 33-00329 33-00330 33-00331 33-00332 33-00342 33-00344 33-00349 33-00351 33-00353 33-00354 33-00355
33-00357 33-00363 33-00364 33-00365 33-00366 33-00368 33-00369 33-00370 33-00371 33-00372 33-00373 33-00374 33-00375 33-00376 33-00379
33-00380 33-00381 33-00382 33-00383 33-00384 33-00385 33-00386 33-00387 33-00388 33-00389 33-00390 33-00391 33-00393 33-00394 33-00395
33-00398 33-00399 33-00400 33-00401 33-00402 33-00403 33-00404 33-00405 33-00406 33-00407 33-00408 33-00410 33-00411 33-00412 33-00413
33-00414 33-00415 33-00418 33-00419 33-00420 33-00421 33-00423 33-00425 33-00426 33-00427 33-00428 33-00429 33-00430 33-00431 33-00432
33-00433 33-00435 33-00436 33-00441 33-00442 3-00445 33-00446 33-00448 33-00450 33-00454 33-00455 33-11099 33-11110 33-70118-FB
33-70134-FB 33-90080B 33-90179-1 33-90203 33-90324-FB 33-90359-FB 92-00002 92-00004  92-0000 92-00001 92-00002 92-00003 92-00004 92-00005
80-020055 80-020070 80-062055
Technology
Areas of Consideration
Pogo Pins
The signal travels on the outside of the structure,
increasing signal path length and distortion. Many
component parts mean more points of potential failure.
Spring Probes
Often an expensive approach.  Commonly a longer
contact height than is optimal.  Have a very complex
structure meaning more potential points of failure.
Hyperboloid / Hypertac / SuperButton /
SuperSpring Contacts
Challenging to assemble into carriers.  Component
wires sometimes separate from body during usage.  
Size is limited to larger pitch/pad configurations.  Not
intended for high mating cycle applications. Long term
reliability may be an issue.
CIN:APSE®
The annealed wire structure often  limits mating
cycles. Only offered in a single material choice which
limits possible applications.  Have just two diameter
choices which limits pitch/pad matching.
Solder
Fragile in harsh environments such as shock,
vibration and high temperatures, prone to cracking.  
Precision placement equipment is very expensive.  
Very difficult to remove for part replacement.  Often not
RoHS compliant due to lead content contamination..
Fuzz Buttons®
Signal travels via shortest path within the Fuzz Button®
structure; diminishing distortion, resistance and
inductance.  Simple single piece architecture means a
more reliable contact.  When used in conjunction with
Hardhats, high mating cycles can be achieved with
little signal degradation.  Always Lead-Free, DFARS
and RoHS compliant.