Echelon Series 6000 Chip databook - Manual (Page 151)

Notes for the figure:
• Maintain a minimum distance of 2 mm between a routed trace and any of the
transformer pads or traces. This distance is especially important for the network
pins (3, 4, 7, and 8) to maintain EMC compliance. The primary and secondary traces
should be kept away from each other as much as possible.
• If you use center-tap capacitors, place them near pin 2 (Primary) and pin 8
(Secondary).
• Vias and other PCB features are not shown. Use standard practices for vias and
trace widths.
• The component callout letters refer to the callouts used in Figure 50 and Figure 51.
Recommendation: Add vias to the ends of each of the pin pad connections (just outside the
SMT pad rectangles) to provide additional mechanical support for the transformer, as shown
in Figure 51. The figure shows the pad trace extended to the via at each end, and slightly
narrowed to distinguish the trace from the pad; use standard layout rules to determine the
size and distances for the traces.
Transformer pad
Trace
Via
Figure 51. Adding Vias to the Transformer Pad Layout
Series 6000 Chip Data Book 139