What is FloTHERM® PACK?

FloTHERM PACK is a unique Web-based product from Mentor Graphics designed to generate reliable, accurate thermal models of IC components, test boards, standard test harnesses and other associated parts with the minimum of effort. FloTHERM PACK generates accurate models 100X faster than conventional approaches. Moreover, FloTHERM PACK is at the leading edge of emerging industry standards such as DELPHI. DELPHI compact modeling standards are being currently adopted by the industry standards body JEDEC. FloTHERM PACK is the only commercial software tool in the market that can actually generate DELPHI compact models!

I am a systems designer, not a semiconductor house. Do I really need FloTHERM PACK?

70% of all licensed FloTHERM PACK users are systems integrators, not semiconductor or package assembly houses! In fact, it is systems integrators that have the most urgent need for predicting junction and case temperatures of their parts in their application environments. FloTHERM PACK’s unique SmartPart methodology means that generating an acceptably accurate model of a component literally takes seconds, and requires only a minimal knowledge of the internal details of the package.

How does FloTHERM PACK work?

FloTHERM PACK consists of a collection of “Smart Part” modules installed on a central Web server. FLOTHERM Users enter data describing the IC package using a standard Web browser (such as Netscape or Internet Explorer), for instance:

  • no of balls
  • substrate conductivity
  • die size
  • substrate metal layer thickness and coverage

These parameters are then used by FloTHERM PACK to generate a FLOTHERM model which can be downloaded to the user's local machine and analyzed using FLOTHERM. If the user has a VRML enabled browser, the models can be previewed in 3D before being generated to ensure that the user input parameters are sensible.

FloTHERM PACK’s SmartPart approach is unique in the software industry as far as electronics package analysis goes. This is because it generates the most accurate models with the minimum of user inputs. Thus users can get an accurate model of their part literally in seconds, by filling in just 2 or 3 input fields!

How is this done? Essentially, the SmartPart approach encapsulates in-built common industry manufacturing and design rules used by most IC component suppliers.  These rules will generate a reasonably accurate package model from a reduced set of input parameters.  The idea is to make the user input only the bare minimum necessary data, and let FloTHERM PACK do the hard work of making intelligent guesses for the rest of the information in the design sheet.

How Does This Help?

The Smart Parts installed on the FloTHERM PACK Web site offer the following benefits to the user:

Best Known Methods
Mentor Graphics has provided specialized thermal analysis software to electronics designers for more than 15 years and has, during that time, built up an enormous bank of knowledge regarding the modeling of these packages. By coding this knowledge into the FloTHERM PACK SmartParts, Mentor Graphics can allow you to take advantage of this knowledge in developing your own models. 

Consistency & Reliability
By using the same SmartParts to develop models of a range of packages, the analyst can be more certain that any differences seen are due to the design of the packages rather than differences in modeling.

Once you've created one model, you'll see just why FloTHERM PACK can cut your model generation time by a factor of 100. Need we say more?

Why is FloTHERM PACK web-based?

The IC packaging industry is a rapidly moving industry and new package styles are being developed almost on a monthly basis. By implementing FloTHERM PACK as a web application, we can implement new SmartParts or update older ones practically in “real time”. This means that customer requests for new features can be turned around much faster than for conventional, stand-alone software. A web-based approach also eliminates the need for users to install any client software locally thus reducing support headaches and minimizing cost.

Does FloTHERM PACK create Detailed or Compact Models?


Detailed models represent package details explicitly, such as:

  • solder balls
  • thermal vias
  • metal layers in organic substrates

A variety of CFD modeling options are provided for each package which allows the user to make simplifications to the models where appropriate. For example, the effect of the solder ball array might be represented as an assembly of individual elements (accurate but computationally more expensive) or as a single block with lumped thermal properties. 

Compact Models are a computationally efficient representation of the package's thermal characteristics. FloTHERM PACK supports two types of compact models - two-resistor and DELPHI. (Both these types of compact models are being currently standardized by the industry standards body JEDEC.)

Two-resistor compact models are generated using computational implementation of the JEDEC standards for the Junction-to-Case and Junction-to-Board resistances. They offer an almost insignificant computational cost, and predict junction temperatures accurate to within 30 % in the worst case. Two-resistor models are a major improvement over traditional single resistor metrics such as Junction-to-Ambient resistance (Theta-JA), which have been shown to be inaccurate to 60% or more.

DELPHI compact models are a revolutionary, new class of compact models that constitute the first incarnation of what are known as Boundary Condition Independent (BCI) compact models. BCI models aim to be boundary condition independent to within a high degree of accuracy (10% or less) for predicting the junction and case temperatures.

DELPHI compact models are an implementation of the methodology proposed by Project DELPHI, and are a significant improvement over two resistor models. In other words, in just about any reasonable electronics cooling environment at the system level, a DELPHI compact model will predict the junction temperature to a high accuracy of the detailed model, while greatly reducing the simulation time.

What part families does FloTHERM PACK Support?

Currently, FloTHERM PACK supports the following parts:

  • Plastic Ball Grid Array (PBGA) – Wirebonded; with or without slugs.
  • PBGA - Flip-Chip, with or without lid.
  • PBGA - Cavity-Down, including SuperBGATM 
  • PBGA - Stacked Die (TFBGA) 
  • Ceramic Ball Grid Array (CBGA) - Wirebonded 
  • CBGA - Flip-Chip, with or without lid. 
  • Tape Ball Grid Array (TBGA). 
  • ChipArrayTM also known as Fine Pitch BGA (FPBGA) or FSBGA.
  • Board-on-Chip BOCTM
  • MicroStarTM
  • Quad Flat No-Lead (QFN) or MLFTM
  • Ceramic Pin Grid Array CPGA - Cavity Up. 
  • CPGA - Cavity Down. 
  • CPGA - Flip Chip. 
  • MicroBGATM 
  • mZ-Ball StackTM
  • Quad Flat Pack’s of various kinds including MQFP, LQFP, TQFP - with and without slugs.
  • Small Outline packages such as SOIC, SOP, SSOP.
  • Thin Small Outline Package (TSOP) and TSSOP; Conventional and Lead-on-Chip leadframes.
  • Exposed Pad versions of popular QFP and SOIC/TSOP packages. 
  • PDIP
  • Plastic Leaded Chip Carrier (PLCC). 
  • Transistor Outline Packages (TO-220, TO-263 or D2PAK)
  • PGA Socket. 
  • Extruded Heatsink. 
  • Pin Fin Heatsink. 
  • Disk Fin Heat Sink. 
  • PCB with user-defined layers and via clusters.
  • Bare die with multiple heat sources.

Package styles currently under development include PPGA, BCC, DSBGA, and a number of power packages.

If you have an urgent need to model a particular package not covered by the current version of FloTHERM PACK, contact Mentor Graphics directly and we'll try our best to add it to our library within just weeks.

I don't have FLOTHERM - can I still use FloTHERM PACK?


FloTHERM PACK generates compact models such as two-resistor and DELPHI, and the resistor network data (e.g. Junction-to-Case resistance and Junction-to-Board resistance) obtained can be used in network calculators or spreadsheets. A number of FloTHERM PACK customers use the tool precisely for this purpose and it is well worth it.

The models that downloaded from FloTHERM PACK can be exported to FLOTHERM.

Call your local Mentor Graphics office or distributor if you'd like to find out more about FLOTHERM. 

Is any training required to use FloTHERM PACK?

Not really.

FloTHERM PACK is so intuitive and easy to use that no specialized training is required. However, if you are completely new to the area of component analysis, you might want to sign up for Mentor Graphics' "Modeling IC Packages with FLOTHERM" course.  Please contact us for further details.

What kind of documentation is available?

FloTHERM PACK documentation is on-line and contained on the Web site. It includes discussions of the input parameters and modeling options for each packages, as well as general information and advice on modeling, and cross-references to other Internet sources on package level thermal modeling.

Does FloTHERM PACK have any other functions or tools?

Yes. FloTHERM PACK includes a collection of standard test configurations such as JEDEC Still Air Tests, Forced Air Tests, JEDEC Ring Cold Plate Tests. It also contains a pre-defined library of standard JEDEC test boards.

How can I access FloTHERM PACK?

All FLOTHERM users with a valid user name and password for the FLOTHERM User Support Area can access FloTHERM PACK for a trial period by simply logging on to the FloTHERM PACK web site at:


and clicking on  option. This will automatically set you up with a 1 month trial license.

FLOTHERM users without a FLOTHERM User Support Area password should apply for one at:


Once the password has been approved (normally 1 to 2 working days) follow the same procedure as above to get a free FloTHERM PACK trial.<![endif]>

What do I need to run FloTHERM PACK?

  1. An Internet connection.
  2. A Web browser - Netscape version 6 or above, or Internet Explorer version 5 or above.
  3. [Optional] A copy of FLOTHERM or TASPCB to run the models.
  4. [Optional] A VRML browser or plug-in for your Web browser is required to preview models. FloTHERM PACK uses VRML Level 1. You can find a list of suitable browsers and plug-ins at: www.web3d.org/vrml/browpi.htm
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