ADS Simulation Experience in Mobile Phone PCB

MatchingTommy Chung

Outline• About FIH & me• RF matching and tuning• Other people simulation process

• Case1• Case2

• What I think about simulation• Disassemble simulation schematic• My Simulation step

• Prepare• Process • compare• Set up

• Case and key point• Conclusion• Summary

About FIH & me

• Foxconn international holding(富智康)• 新北市土城區民生街四號(靠近頂埔捷運站)• Main :

• Smart phone, wearable device.• Me

• Now• RF engineer

• Past• Power semiconductor(SiC)• photonic crystal• Antenna simulation

RF matching and tuning

Other simulation process: case 10.

5

1.0

2.0

5.0 10 20

20

-20

10

-10

5.0

-5.0

2.0

-2.0

1.0

-1.0

0.5

-0.5

0.2

-0.2

freq (1.700GHz to 2.000GHz)

A1M

_PC

S_D

CS

_PA

OU

T_a

dfi..

S(9

,9)

Other simulation process: case 2Start

Use RF cable and NA to extrction trace loss and S-

parameter

Combine trace and parts S2P to get Schematic

End

Matching trend

Outline• About FIH & me• RF matching and tuning• Other people simulation process

• Case1• Case2

• What I think about simulation• Disassemble simulation schematic• My Simulation step

• Prepare• Process • compare• Set up

• Case and key point• Conclusion• Summary

What I think about simulation

• Less welding • Reduce damage

• Momentum • For ours simulation is reliable or not.

• Component S-parameter • Should I measure it?

• Layout stack up • How to describe to ADS?

Disassemble simulation schematic

50ohm

Z = 50ohm

Zant= 50W || 7.5 nH

Ztx = 50W + 4.0 nH

Zrx = 50W

Z = 50ohm

conjugate

0.5

1.0

2.0

5.0 10 20

20

-20

10

-10

5.0

-5.0

2.0

-2.0

1.0

-1.0

0.5

-0.5

0.2

-0.2

freq (500.0MHz to 2.000GHz)

conj

(S(1

,1))

S(1

,1)

Load pull

chip

wire

C and L

My Simulation-prepare

1.51 1.52 1.53 1.54 1.55 1.56 1.57 1.58 1.591.50 1.60

-0.087

-0.086

-0.085

-0.084

-0.083

-0.082

-0.088

-0.081

freq, GHz

dB(A

1M_G

PS

_AN

T_a

dfi..

S(1

,2))

0.5

1.0

2.0

5.0 10 20

20

-20

10

-10

5.0

-5.0

2.0

-2.0

1.0

-1.0

0.5

-0.5

0.2

-0.2

freq (1.500GHz to 1.600GHz)

A1M

_GP

S_A

NT

_adf

i..S

(1,1

)A

1M_G

PS

_AN

T_a

dfi..

S(2

,2)

My simulation-process

Start

Extraction Adfi file,and load adfi to ADS

Load adfi file to ADS

Set up simulation parameter

Run momentum

load adfi to A S

Load adfi file to ADS

End

Set up simulation parameter

Run momentum

Place component on schematic

Get insertion loss and smith chart

My simulation-compare

Start

Use RF cable and NA to extrction trace loss and S-

parameter

Combine trace and parts S2P to get Schematic

End

Matching trend

Start

Extraction Adfi file,and load adfi to ADS

Load adfi file to ADS

End

Set up simulation parameter

Run momentum

Place component on schematic

Get insertion loss and smith chart

My simulation-set up

• Mesh not over 60000 matrix• Stack must follow real stack• Less stack up is best• Port and GND follow real• Frequency not to wide• Thick:2D,via:lumped,mesh:10• Please use Queue and auto create EM model• Remember place real component to your schematic

Outline• About FIH & me• RF matching and tuning• Other people simulation process

• Case1• Case2

• What I think about simulation• Disassemble simulation schematic• My Simulation step

• Prepare• Process• compare • Set up

• Case and key point• Conclusion• Summary

Case and key point-time

Simulation time compare(mesh >60000) mesh 30000CPU Intel Xeon @2.6GHz(8 core)*2 8 core i5(4 core) i5(4 core)

RAM RAM: 132GB 32GB 16GB 16GB

speed time 1hour 8hours >12 hours 0.5 hours

Case and key point-thick,via

• Physical Model• Keysight thick : 2D ,via : 2D• Me thick : 2d , via : lumped

Case and key point-thick,via

Smith chart compare

Case and key point-thick,via

Insertion loss compare

Case and key point-component

• Conponent : ideal or real

Ref

1 2

Term1 Term3

SNP1

Term5 Term7C1

Num=1

Z=50 Ohm

Num=3

Z=50 Ohm

File="D:\conponent_package\0.5pF.s2p"

Num=5

Z=50 Ohm

Num=7

Z=50 OhmC=0.5 pF

Term Term

S2P

Term TermC

0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4 2.6 2.80.6 3.0

-12

-10

-8

-6

-4

-14

-2

freq, GHz

dB(S

(1,3

))dB

(S(5

,7))

0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4 2.6 2.80.6 3.0

-0.06

-0.04

-0.02

-0.08

0.00

freq, GHz

dB(S

(2,4

))dB

(S(6

,8))

0.5pF

100pF

Ref

1 2

Term1 Term3

SNP1

Term5 Term7L1

Num=1

Z=50 Ohm

Num=3

Z=50 Ohm

File="D:\conponent_package\HKQ0603U_0N6.s2p"

Num=5

Z=50 Ohm

Num=7

Z=50 OhmL=0.6 nHR=

Term Term

S2P

Term TermL

0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4 2.6 2.80.6 3.0

-40

-35

-30

-25

-20

-15

-10

-45

-5

freq, GHz

dB(S

(2,4

))dB

(S(6

,8))

0.6nH

39nH

0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4 2.6 2.80.6 3.0

-0.05

-0.04

-0.03

-0.02

-0.01

-0.06

0.00

freq, GHz

dB(S

(1,3

))dB

(S(5

,7))

Case and key point-gnd

Case and key point-Stack up

prediction

finalFinal in ADS

Case and key point-Stack up

Case and key point-Stack up

Case and key point-trace loss

• The trace loss is about 0.2dB(2GHz)

Case and key point-trace loss

• Layer2 GND

• Add two via from • layer2 to layer3

• Add two via from • layer2 to layer1

Conclusion

• The skill is enough to estimate the insertion loss and smith chart for ours matching.

• If we want to get total trace loss or smith chart accurately, we should measure the s-parameter of chip.

• Anyone want to simulate more region ,maybe use server or SIPRO.

Summary

• Mesh• Real Stack up• GND port• Frequency • Thick:2D,via:lumped,mesh:10• Queue• real component

Q&A