Amphenol Spectra-Strip
SkewClear
®
720 Sherman Avenue, Hamden CT, 06514 USA
SkewClear EXD
tm
(Extended Distance) Cables for
25Gb ++ applications
US Patent 7,790,981 B2
Introduction
EXD is the patented next generation solution for
applications such as SFP+, QSFP+, SAS 4.0, IEEE
802.3bj and FDR / EDR InfiniBand, where the
periodic structure of traditional spiral shield
constructions in the twinax pair shield design
causes a resonance of attenuation response at
high frequency (see red traces below).
Spectra-Strip’s EXD SkewClear® product line of high
precision bulk cable is designed for high frequency
applications carrying 10Gb ++ signals. In cables such
as this, minimum insertion loss, minimum deviation,
and flattest possible frequency response over a wide
band is critical for successful signal recovery in either
active or passive cables. Precision extrusion, pair
shielding, and cabling are key elements necessary
for consistent performance. As the biggest
contributor to the total interconnect link performance,
one of the biggest technical challenges that confronts
any cable manufacturer is attenuation stability, i.e.,
how consistent all the pairs in the cable are relative
to each other. Since all the standards specify
maximum assembly insertion loss at a given
frequency, it is crucial that all the pairs meet a
specified
MAXIMUM
attenuation at the fundamental
frequency of interest, as well as some harmonic
content.
In short, the cable is only as good as the worst pair in the cable, as this will be the one that limits
the overall channel performance. It is important to note that Spectra-Strip specifies
MAXIMUM
not
NOMINAL
attenuation performance at multiple frequencies on all of its EXD cables.
www.spectra-strip.com
800-846-6400
1
Revision G © 2014 Amphenol Spectra-Strip,
all rights reserved. Specifications
are subject to change without notice.
Amphenol Spectra-Strip
SkewClear
®
720 Sherman Avenue, Hamden CT, 06514 USA
The EXD Advantage Over Traditional Spiral Wrap Shield
Comparison: EXD vs. EXF vs. Standard SkewClear 30 AWG
100 ohm
EXD Features / Benefits:
No suckout (resonance) up to 23GHz. Harmonic signal content is preserved
Significant Improvement in high frequency attenuation for more margin
Maximum attenuation specified for all pairs
RoHS / REACH compliant
UL CL2 / UL FT4 rated standard
Standard shield materials, and same stripping process as standard cable
Potential for AWG size reduction. Available 30 through 24 AWG
Odd AWG sizes (29, 27, 25 AWG) available upon request
Super flexible PVC, UL VW1, or halogen free jackets also available
800-846-6400
2
www.spectra-strip.com
Revision G © 2014 Amphenol Spectra-Strip,
all rights reserved. Specifications
are subject to change without notice.
Amphenol Spectra-Strip
SkewClear
®
720 Sherman Avenue, Hamden CT, 06514 USA
EXD Attenuation comparison 30, 28, 26, 24 AWG 100 ohm
26 AWG Mini SAS HD EXD vs. 24 AWG spiral EXF 100 ohm
EXD Attenuation comparison 30, 28 AWG
85 ohm
www.spectra-strip.com
800-846-6400
3
Revision G © 2014 Amphenol Spectra-Strip,
all rights reserved. Specifications
are subject to change without notice.
Amphenol Spectra-Strip
SkewClear
®
720 Sherman Avenue, Hamden CT, 06514 USA
EXD Cable Specifications
Conductor
Dielectric
Drain wire
Pair shield
Overall
Shield
Spiral
wrapped
aluminum /
polyester
tape +
85%
coverage tin
copper braid
Jacket / UL
Voltage / Temp
rating
Solid silver
plated copper
per ASTM
B298
Solid
polyolefin
Solid tinned
copper per
ASTM B3
Longitudinal
aluminum /
polyester tape +
polyester wrap
PVC
UL CL2
UL FT4
-40 to +75C
300V
Part
Number
160-3099-979
160-2899-970
160-2799-998
160-2699-981
160-2599-999
160-2499-975
166-2699-873
166-3099-941
166-2899-921
166-2799-998
166-2699-936
166-2699-941
166-2599-992
166-2499-940
166-3099-904
166-2899-905
166-2699-910
Description
1X 30 AWG
1X 28 AWG
1X 27AWG
1X 26 AWG
1X 25 AWG
1X 24 AWG
2X 26 AWG
4X 30 AWG
4X 28 AWG
4X 27AWG
4X 26 AWG
4X 26 AWG
4X 25 AWG
4X 24 AWG
12X 30 AWG
12X 28 AWG
12X 26 AWG
Diameter
inches
(mm)
0.175
(4.44)
0.195
(4.95)
0.220
(5.59)
0.220
(5.59)
0.230
(5.84)
0.230
(5.84)
0.290
(7.36)
0.270
(6.89)
0.330
(8.38)
0.330
(8.38)
.385
(9.78)
0.380
(9.65)
0.400
(10.16)
0.435
(11.05)
0.440
(11.18)
0.520
(.13.21)
0.610
(15.49)
Min bend
radius inches
(mm)
1.05
(26.67)
1.17
(29.72)
1.32
(35.53)
1.32
(35.53)
1.38
(35.05
1.38
(35.05
1.74
(44.20)
1.62
(41.15)
1.98
(50.29)
1.98
(50.29)
2.31
(58.67)
2.28
(57.91)
2.40
(60.96)
2.61
(66.29)
2.64
(67.06)
3.12
(79.24)
3.66
(92.96)
Impedance
100
5
100
5
100
5
100
5
100
5
100
5
100
5
100
5
100
5
100
5
100
5
100
5
100
5
100
5
100
5
100
5
100
5
Maximum
within pair
skew
35 ps / 4m
40 ps / 5m
50 ps / 6m
60 ps / 7.5m
80 ps/10m
80 ps / 10m
70 ps / 10m
35 ps / 4m
40 ps / 5m
50 ps / 6m
100 ps / 15m
60 ps / 7.5m
80 ps / 10m
80 ps / 10m
60 ps / 7.5m
70 ps / 10m
70 ps / 10m
Maximum
attenuation @
20 GHz
8.20 dB / m
7.00 dB / m
6.17 dB / m
5.35 dB / m
4.80 dB / m
4.28 dB / m
4.95 dB / m
8.20 dB / m
7.00 dB / m
6.17 dB / m
4.95 dB / m
5.35 dB / m
4.80 dB / m
4.28 dB / m
8.20 dB / m
7.00 dB / m
5.35 dB / m
www.spectra-strip.com
800-846-6400
4
Revision G © 2014 Amphenol Spectra-Strip,
all rights reserved. Specifications
are subject to change without notice.
