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| From [log in to unmask] Sat Apr 27 15: |
30:23 1996 |
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The overall question is how to calculate the current carrying capacity
of a thermal relief.
IPC - D-275 indicates that the total area of the thermal ties should
be used to calculate the current.
However, the chart on page 10, to calculate current capacity of a line
makes a assumption that this is
a long free line.
Since the thermal ties are very short (.010) and tied to a plane. This
adds a lot of heat-sink and it looks to me like this
needs to be taken into account when calculating current capacity.
Any experience out there with this problem?
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