Page 55 - Chip Scale Review_November December_2021-digital
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1.3X better) based on measurements at
16GHz. As a result, the insertion loss was
improved by -0.15dB (about 10.5X) and
the return loss was improved by -15.42dB
(about 3X). This shows that insertion
loss, return loss, and crosstalk are all
improved compared to the elastomer
socket. However, the coaxial spring socket
has 53% insertion loss characteristics
compared to the coaxial elastomer socket
based on measurements at 16GHz. Return
loss characteristics tend to drop by 14%
and crosstalk by 30% because of the large
number of components and the long signal
length to secure the spring tension. This
means that the coaxial elastomer socket is
shorter than the coaxial spring socket and
Table 1: Frequency domain analysis comparison.
Figure 6: Eye diagrams of: a) a spring socket; b) elastomer socket; c) coaxial spring socket; and d) a coaxial elastomer socket.
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