Chapter 10
Connector and Cables
Trillium Compact User Guide
16889R5
2014-03-04
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10.3 Cable Design Guidelines
If you are designing your own cable, use the following cable design guidelines:
Include effective EMI shielding in the cable design.
Use the DGND for the return currents of the control signals. These are CTRL
/
RX and
UVW/TX.
Use the AGND for the return currents of the analog signals. These are CAL_SIG and
MAXIMUM MASS POSITION.
Ensure that the cable capacitance does not exceed 10 nF. For Nanometrics cables,
this corresponds to 25 m.
Ensure the cable length is sufficient to allow for strain relief.
Ensure that the peak current requirement of the Trillium Compact does not result in a
voltage drop along the cable which takes the power supply voltage below the
minimum required at the Trillium Compact. See
Table 8-5 “Power specifications”
Ensure the cable is watertight.
Check the cable electrically after assembly. In particular, ensure that the individual
and overall shields are not shorted together unless so specified.
Make sure cables are labelled with correct drawing numbers and revisions.
Make sure the digitizer is configured so that the default states of the control lines put
the Trillium Compact in the desired state.
Double-shielded twisted-pair cable is a good choice for EMI shielding as the twisted pairs
provide magnetic shielding, an inner shield grounded at the digitizer provides good electric
field shielding, and a continuous outer shield provides good high RF shielding.