Cable
assemblies shall meet the following characteristics:
- The minimum conductor size shall be #28AWG (0.080
mm2 )
- The characteristic unbalanced
impedance of each signal and ground pair shall be 62 Ohm,
over the frequency band of 4-16 MHz.
- The unbalanced capacitance of each
cable pair shall not exceed 107 pF/m at 1 MHz.
- The maximum dc resistance of each
cable wire shall be 0.232 ./m at 20C.
- Maximum end-to-end attenuation
shall not exceed 1.5 dB at 5 MHz.
- The maximum propagation delay of
the cable shall be 58 ns.
- The maximum propagation delay
difference between any two signal pairs shall be 2.5 ns.
- The maximum zero-to-peak crosstalk
noise (both near end and far end) shall be 10% as measured with a 5.0 ns rise/fall 2 MHz
square wave, with each pair (source and victim) terminated in its char-acteristic
impedance at both ends (see figure 33).
- The cable shall have a minimum of
85% optical braid coverage over the foil.
- The cable shield shall be connected
to the connector backshell using a 360° concentric method low impedence connection. A
pigtail type connection is not acceptable.
- Each signal pair shall be twisted
at least 36 turns per meter.
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