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3.1. Tolerance for X-axis Alignment of Castellation

Misalignment of castellation to the land pad should not exceed 0.2 mm or approximately half the width of the cas-

tellation during placement of the unit. The castellations will completely self-align to the pads during solder reflow as

seen in the pictures below.

3.2. Tolerance for Rotational (Theta) Misalignment

Units when mounted should not be rotated more than ± 2 degrees with reference to center X-Y as specified in Fig-

ure 2. Pictures 3 and 4 show units before and after reflow. Units with a Theta misalignment of more than 2 degrees

do not completely self-align after reflow. Units with ± 2 degree rotational or Theta misalignment self-aligned com-

pletely after solder reflow.

Picture 1. Castellation misaligned to land pads in X-axis before

reflow.

Picture 2. Castellation self-align to land pads after reflow.

Picture 3. Unit is rotated before reflow.

Picture 4. Unit self-aligns after reflow.