John:
This will be my concluding note on this subject prior to
the Symposium. I have tuned the analyses done yesterday and that data
follows.
For a single 1.4mil ground plane with a single IC located
52mm from the Baseplate edge, a 1.0W dissipation results in a temperature rise
of 38.2°C
For a double 1.4mil ground plane with a single IC located
28mm from the Baseplate edge, a 1.0W dissipation results in a temperature rise
of 21.1°C.
For a double 1.4mil ground plane with TWO ICs, spaced 40mm
and both located 28mm from the Baseplate edge, a 1.0W dissipation in each IC
results in temperature rises of 26.1°C (one at 26.0 and the other at 26.2).
Total dissipation here is 2.0W.
In other words, doubling the ICs, with this spacing, only
added ~24% to the temperature rise. This shows you how this module design
handles the kind of power situations that you have in the URx.
See you in Pittsburgh?
’73,