Specifications

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Page 97
安捷倫科技高頻元件量測研討會
Feb.23, 2006
Important Design Feedback
Designing for 50 Ohm single ended line is not the same as a 100 Ohm differential
line.
Characterizing with single ended TDR will not measure differential impedance.
Design the daughter cards with as much care as the backplane.
Most discontinuities from connectors are not from the connectors- they are from
the via fields.
Optimizing connectors is all about optimizing the circuit board via field layout.
Design for test: add copper fills for microprobing
Page 98
安捷倫科技高頻元件量測研討會
Feb.23, 2006
Differential TDR from Both Ends
TDD11 TDD22
similar connector,
reduced bandwidth
1 nsec/div 1 nsec/div
m
i
r
r
o
r
e
d
Port 1 Port 2
100 Ω