Hi,

        We are using these 1W devices at about half their rated capacity (.5W) on
FR4 board material and are seeing discoloration of the FR4. The part is
capable of reaching about 175 degrees C. FR4 would probably start measling
well before it reaches that temperature. Has anyone seen any rules of thumb
for adding additional copper to the PCB footprint to spread the heat out so
discoloration or worse would not occur.

Tim
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