Interlink Electronics Micro Joystick - Manual (Page 21)

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19
MicroJoystick
Integration Guide
Attaching a Flexible-Circuit Tail to the MicroJoystick
When attaching the flexible-circuit tail to the MicroJoystick’s conductive traces, care should be
taken to ensure that the tail is properly aligned to the conductive traces on the MicroJoystick’s
base. The sketch below illustrates a properly aligned tail and an improperly aligned tail.
When handling conductive adhesives, use care to avoid wrinkling the tape which could cause
leakage in the X or Y directions or open circuits. The adhesives should not be touched with bare
fingers, and the conductive traces of the MicroJoystick should be clean (i.e., free from dirt, dust,
oil or other contaminates). Contaminants on the adhesive or MicroJoystick can impair electrical
conductivity between the MicroJoystick and the flexible circuit. If the conductive traces of the
MicroJoystick need to be cleaned, use a soft material (e.g., a cotton swab) moistened with
isopropyl alcohol. The cotton swab should only be moistened with alcohol, not dripping. This will
help prevent the alcohol from wicking into the captuator base. Use care not to scratch the
conductive traces when cleaning the MicroJoystick.
Peel forces applied to the bond joint can cause the adhesive to delaminate. If peel forces are
likely to be applied to the joint, a method of mechanically reinforcing the joint should be devised
(as recommended in the section above, a mechanical reinforcement should always be used with
pressure-sensitive Z-axis adhesives). For example, if a long tail is attached to the MicroJoystick,
the alignment of the tail may not be perfect. If a mis-aligned tail is bent when placed into a
connector, peel forces could be transferred to the bond joint. To prevent delamination of the
adhesive, a mechanical compressive force should be applied to the bond joint. The sketch on the
next page details this situation.
PROPERLY ALIGNED TAIL MIS-ALIGNED TAIL