imbera engineers used flotherm thermal simulation software from flomerics to optimize early in the design phase the thermal management of a series of integrated module boards (imbs) that utilize a unique production process. the thermal properties of the new technology were difficult to determine since there is no standard for defining the thermal resistance of a printed circuit board (pcb) in which an integrated circuit (ic) is embedded. simulations provided fundamental information about the thermal behavior of the structure, such as the heat flow path. this made it possible for several thermal enhancement methods to be evaluated with relatively little expenditure of time or money.

imbera is a joint venture of aspocomp group oyj and elcoteq network corporation that is developing an innovative production process that integrates active components inside the pcb structure. the process combines aspocomp's pcb expertise with elcoteq's specialized electronics manufacturing and testing know-how. pcb manufacturing, component packaging, and assembly are incorporated into a single manufacturing process. all interconnections between the ic and substrate are processed simultaneously.

the thermal properties of the new technology were challenging to define because the technology is so new and is developing very rapidly. tight schedules limited the number of prototyping runs that could be executed. flotherm software from flomerics is ideally suited to this type of complicated electronics cooling problem because it is specially designed for electronic cooling applications. flotherm provides an abundant supply of thermal model libraries for existing components and tools that allow users to assemble models from libraries, avoiding the need to create them from scratch.

imbera engineers used flotherm to model two types of imb structures, ball grid array (bga) modules and ics embedded in motherboards, in a standard still air environment. simulations provided fundamental information about the behavior of the structure. the simulation results made it possible for imbera engineers to optimize the various methods afforded by imb technology to keep the product operating temperature within specifications. in addition, the thermal simulations helped keep product cost low by eliminating the need to overdesign.

the simulation models were validated by performing measurements with micred’s "t3ster" thermal tester. the t3ster is unique in its ability to test up to eight components at one time and analyze the results as the test is being performed so the results are immediately available.

"when working with new technology and within several customer projects of different application areas, the need to define thermal requirements early is a necessity," said an imbera thermal specialist. "performing thermal simulations with flotherm as part of the design process is a good solution for us. many of our customers also use flotherm, so exchanging models is straightforward. also, flomerics’ design services are useful to us, for example when electromagnetic compatibility (emc) simulations are needed."

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