ANSOFT ePhysics V1'0: Technology Overview and Applications

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ANSOFT ePhysics V1.0 Technology Overview and
Applications
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Presentation Summary
About ePhysics Features in ePhysics V1.0 Markets
Applications Conclusions
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ePhysics for Electromagnetic Applications
HFSS EM high frequency
ePhysics - Thermal - Stress - CFD - .
Maxwell EM low frequency
Electrostatic
Electric
Magnetostatic
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Higher Level Analysis
Geometry
CAD Level
Maxwell (low frequency)
HFSS (high frequency)
Electro-magnetics Level
ePhysics Thermal/Stress
Multi-physics Level
Optimetrics Parametrics/Optimization/Sensitivity
Analysis
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ePhysics TM Functional Links
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Presentation Summary
About ePhysics Features in ePhysics V1.0 Markets
Applications Conclusions
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3D Thermal Transient
initial condition
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Solution Process HFSS - Thermal
Initial (coarse) thermal mesh
Controls both accuracy of thermal solution AND
accuracy of power loss mapping
Maxwell/HFSS
Thermal
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Heat Transfer Mechanisms
Convection
Radiation
Conduction
Natural
Forced
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Frequently Used ThermalSources
On solids
On surfaces, surface can be between objects
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Frequently Used Thermal Boundary Conditions
Can be functional! (temperature dependent) Can
include radiation if needed! Models CFD effects
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Structural analysis(basic quantities,
relationships)
Volume force density
Strain tensor
Equilibrium condition
Boundary condition
External traction
Stress tensor
Constitutive relations
E Youngs modulus ? Poissons ratio a
coeff. of thermal expansion G shear
modulus
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Structural Boundary Conditions
Homogeneous displacement (On any surface of a
group of connected bodies)
Rigid body equilibrium is guaranteed
Rigid body equilibrium is not guaranteed,
user can choose an anchored boundary condition)
Tangential displacement (usually needs a local
coordinate system to be defined)
Rigid body equilibrium is not guaranteed,
user can choose an anchored boundary condition)
Normal displacement (a local coordinate system is
not necessary)
Note rigid body motion must be eliminated to
avoid singular structural problem
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Presentation Summary
About ePhysics Features in ePhysics
V1.0 Applications Conclusions
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Schottky Diode Structure
10 mm
leadframe
case
chip
wire
16 mm
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Thermal Sources and Boundary Conditions
28.8 W (50) active area
28.8 W (50)
Dirichlet Boundary Condition 25 oC
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Results
Mesh detail
Steady state temperature distribution
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IC structure in HF incident field
Top plane heated by incident wave
Metal ground planes vias imbedded in ceramic
block
Temperature distribution on ceramic block after
200 s
Temperature distribution on cross section
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IGBT Application(geometry)
Molding
Current path
Copper piece
Solder layers
Dielectric
Aluminum back plane
Heatsink
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IGBT Application(results)
Mesh detail
Heat flow vector distribution
Temperature distribution
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Solenoid thermal modelfor injector
Convective BC on all exterior surfaces
Housing
Coil
Armature
Resin
Needle
Seat
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CPGA Packaging
Intel Ceramic Pin Grid Array Package
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Typical PCB
Layer 1 (FR4)
Layer 2 (FR4)
Layer i (FR4)
Copper
Layer N (FR4)

• 4 layers FR4 with 0.25 W/m K
• 2 internal layers of copper with 390 W/m K
• 35 mm thick copper layers (1oz/ft2)

Maxwell thermal conductivity tensor
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ePhysics Thermal Model (CPGA)
Ceramic top
Ceramic frame
Die
Metallic cap
Pins
Socket
Socket pins
Pcb
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ePhysics Results CPGA
Temperature profile
Heat flow
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ePhysics Thermal Model (SBGA)
Cu heat spreader
Die attach
Adhesive
Copper ring
Mold compound
Die
Multilayer
BGA
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ePhysics Results for SBGA Model
lt10 heat flow
0.66 W
2W
gt90 heat flow
1.14 W
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PCB Level Analysis
Forced convection BCs on the PCB top and bottom
surfaces
3 W
Air flow 5 m/s
230 mm
6 W
230 mm
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PCB Level Analysis(results)
Temperature distribution in a cross section
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High Power Handling HF filters
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Presentation Summary
About ePhysics Features in ePhysics
V1.0 Applications Conclusions
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Conclusions-Main ePhysics V 1.0 features-

• Electromagnetic power loss density distribution
  mapped automatically to thermal problem mesh
• All major heat transfer mechanisms implemented
  (conduction, convection, radiation)
• Non-linear steady state and transient thermal
  solvers
• Thermal (steady state transient) coupling to
  stress
• Functional (temperature dependent) thermal
  boundary conditions