How to Optimize Design of Power MOSFET on High Performance ...cn.21ic.com/ebook_download/microsite/power/英飞凌.pdf · Low Voltage Drives require high current capacity and Low

For internal use only

How to Optimize Design of Power MOSFET on High Performance Low Voltage Drives

Ryan Zhou(周成军)Power Management & SupplyInfineon Technologies China Co,. Ltd

For internal use only26.07.2011

Low Voltage Drives OverviewLow Voltage Drives Overview

Product Qualifications & Team StructureProduct Qualifications & Team StructureInfineon AdvantageInfineon Advantage

Table of contents

Product Qualifications & Team StructureProduct Qualifications & Team StructureDesign ConsiderationsDesign Considerations

Product Qualifications & Team StructureProduct Qualifications & Team StructureSummarySummary




Table of contents




Drives: A Multifaceted Application

12/13/2010


Silicon content inside

Brushed:

, forklift…fan, cordless tool, eBike/Scooter

fan, cordless tool, eBike/Scooter…

Brushless:

Most of the applications could be designed with brushed OR brushless motors, but most of them need a minimum of silicon for control.

Only the simplest ones (e. g. unregulated fans) can work as a brushless motor without any silicon inside

What can we find inside the housing of the power electronics?

Examples


Silicon content inside I

Brushed DC(with PWM, simplest form)

Minimum 1 switch (plus freewheeling diode)

Motor(e-)bike: lots of silicon, Fullpak

Examples:

Cordless screw driver: two IPP015N04 in parallel(Direction control with mechanical switch)

Fan: 1*S308


Silicon content inside II

Brushed DC(with PWM, including direction control)

4 switches

Examples:

Cordless screw driver: 4*3 CanPAK in parallel


Silicon content inside III

Brushless DC

4 or 6 (or more like 8, 10 etc.) switches

Examples:

Fan: 4*SuperS08

Cordless screw driver: 6*2 SuperSO8 in parallel

Forklift: 6*20 + 6*15 FullPAK


System Voltage and the right MOSFET

12/13/2010

12 24 48 72 80 110

200/250

150

120

100

75/80

60

40

30

25

MOSFET Voltage [V]

System Voltage [V]


Low Voltage Drives requirehigh current capacity and Low RDS(on)

Wide range of system power from 1W to 50,000W

12/13/2010

Individual solution depending on customer´s design

Lowest on resistance (RDS(on)) is required!

Low Voltage‘ Drives A high-current application




Table of contents



Best in Class product provided Best in Class product provided

New Package for High Power New Package for High Power


Infineon provides Lowest RDS(on) for Low Voltage Drives Application

12/13/2010

SuperSO8 D2PAK

With Lowest RDS(on) in all required voltage classes and Best qualityInfineon offers the right products for Low Voltage Drives

For internal use only2011-7-26

Infineon Best in Class Products

D²PAK-7 pin D²PAK TO-220

30V LL IPB009N03L G IPB034N03L G IPP034N03L G

40V LL IPB011N04L G IPB015N04L G IPP039N04L G

40V NL IPB011N04N G IPB015N04N G IPP015N04N G

60V LL IPB016N06L3 G IPB019N06L3 G IPP037N06L3 G

60V NL IPB017N06N3 G IPB021N06N3 G IPP024N06N3 G

75V IPB031NE7N3 G IPP023NE7N3 G

80V IPB019N08N3 G IPB025N08N3 G IPP028N08N3 G




200V IPB107N20N3 G IPP110N20N3 G

250V IPB200N25N3 G IPP200N25N3 G

300V IPB41XN30N IPP41XN30N

Grey: Upcoming products, will be released in Q4 2011




Table of contents



Best in Class product provided Best in Class product provided

New Package for High Power New Package for High Power


TO-Leadless:60% Space Reduction

12/13/2010

4.4mm

9.9mm

11.7mm

2.3mm

10.0mm 15mm

Footprint: 150 mm2

Footprint: 115 mm2

30% Footprint Reduction

50% Hight Reduction


30% Higher Current Capability

12/13/2010

High

Power Density

High Electrical

Performance

D²PAK-7 pin TO-Leadless

Footprint [mm2] 150 115

Package Height[mm] 4.4 2.3

PackageResistance + + + + +

RDS(on) + + + + +

CurrentCapability [A] 180 250

Inductivity [nH] 5 1~2

30% Current Capability Increasing


Best Thermal Performance

12/13/2010

D²PAK-7 pin TO-Leadless

Static ThermalPerformance + + + + + +

DynamicThermal

Performance+ + + + + +

Package Quality Automotive Automotive

Thermal

Performance

High

Reliability


Planned Product of Low Voltage in TO-Leadless

12/13/2010

Voltage Class RDS(on)@ 10V[mΩΩ]

60V

75V<1

<1.8100V <2.5150V

200V<6.5

<10.5




Table of contents



Thermal Resistance in Real Application Thermal Resistance in Real Application

Parallelization of MOSFET Parallelization of MOSFET


Question?

Is the information of RthJC in the datasheet OK for IMS?

Do I need additional safety margins for calculation/simulation?

How big is the influence of a smaller chip size?


D2PAK on customer IMS

Silicon Solder

Copper leadframeSolder MOSFET→IMS

Copper tracksCustomer materialAluminum carrier

Heatsink

Hea

t tra

nsfe

r



Silicon Solder

Copper leadframeSolder MOSFET→IMS

Copper tracksCustomer materialAluminum carrier

Heatsink

Hea

t tra

nsfe

r


D2PAK on Customer IMS

Thermal equivalent schematic:

Pv

Silicon Solder Leadframe

Bond wires

IMS etc.

MOSFET

Ambient

Silicon Solder

Copper leadframe

Solder MOSFET→IMS

Copper tracksDenka K-1/TH-1Aluminum carrier

HeatsinkH

eat

tran

sfer

Silicon Solder

Copper leadframe

Solder MOSFET→IMS


HeatsinkH

eat

tran

sfer



Thermal equivalent schematic:

Pv

Silicon Solder Leadframe

Bond wires

IMS etc.

MOSFET

Ambient

ZthJC [K/W]

D=tp/T

ZthJC [K/W]

D=tp/T

IPB072N15

IPB108N15

Silicon Solder

Copper leadframe

Solder MOSFET→IMS


HeatsinkH

eat

tran

sfer

Silicon Solder

Copper leadframe

Solder MOSFET→IMS


HeatsinkH

eat

tran

sfer


Calculation (straightforward)

RthJCmax

(datasheet)

Area of leadframe (ca. 8mm*8mm=64mm2)

Thickness of insulation material: 80µm (or 100µm FR4)

RthHeatsink etc. neglected (<0.1K/W)

Assumptions: THeatsink=40°C; Ploss=10W

IPB072… IPB108…


Results calculation (straightforward)

→TJ=THeatsink + Ploss * (RthIMS+RthJC)

Calculated junction temperatures


Thermal Simulation:customer material 2 (2W/(m*K) 80µm

IPB072N15

Tmax=49.7°C

IPB108N15

Tmax=51.3°C

TOP Bottom Insulation


Thermal Simulation:FR4 (0.3W/(m*K) 100µm

IPB072N15

Tmax=90.4°C

IPB108N15

Tmax=91.7°C

TOP Bottom Insulation


Calculation vs. simulation

IPB072N15 IPB108N15Calculation Simulation Calculation Simulation

Mat 1 (80µm) 48.1 46.5 50.1 48.0 Mat 2 (80µm) 51.3 49.7 53.3 51.3 FR4 (100µm) 97.1 90.4 99.1 91.7

Calculations show everytime higher junction temperatures than simulations

Maximum junction temperatures [°C]


Reasons for differences calculation/simulation

1) Method of measuring the RthJC

2) High safety margins in INFINEON datasheet parameters

3) Soldering parts results in better overall Rth

4) Thick leadframe of D2PAK (1.27mm) spreads the heat

→ Reduced chip size does not result in dramatic worse thermal behavior in D2PAK

Conclusion:




Table of contents



Thermal Resistance in Real Application Thermal Resistance in Real Application

Parallelization of MOSFET Parallelization of MOSFET


Simulation setup

defined setup for measuring the low side MOSFETs

components that have influences on the symmetrical behavior

external gate resistor RG,ext

threshold voltage VGSth

layout

only change one component per simulation

comparison with drain current ID

10Ω

10Ω

0nH

2nH 2nH


ID Waveform

high drain current ID peak

oscillation because of the source inductivity

drain current ID of the two MOSFETs are completely symmetric


RG,ext with 2Ω difference

CONCLUSION

nearly no influence on the switching behavior

RG,ext of 10Ω with tolerance ±5%

differences in current proportioning smaller than this simulation

change RG,ext from 10Ω to 12Ω.


Threshold voltage difference of 0.4V

VGSth of DUT1 is 0.4V higher than VGSth of DUT2

CONCLUSION

0.4V variations occur on a single wafer

nearly no influence


CONCLUSION

In this setup there are higher influences

Threshold volatage difference of 2V

VGSth of DUT1 is 2V higher than VGSth of DUT2


Unsymmetrical layout

conductance: ~10nH

CONCLUSION

1cm copper track corresponds to ~10nH inductance

Highest influence on the symmetric behavior


Coclusion case II

RG,ext (or RG,int/CGS)

Parasytic source inductance

Gate Threshold Voltage

Layout!

low influence

high influence




Table of contents

Product Qualifications & Team StructureProduct Qualifications & Team StructureDesign Considerations Design Considerations



Summary

Infineon offers best in class product for low voltage drives

New package TO-Leadless planned to give better performance.

Thermal condition plays an important role to motor drive.

Rthjc of power device will not be so important comparison with system thermal resistance as a whole.

In real application, engineers need to pay more attention to layout design.



Documents

How to Optimize Design of Power MOSFET on High Performance ...cn.21ic.com/ebook_download/microsite/power/英飞凌.pdf · Low Voltage Drives require high current capacity and Low