Black box modelingfor EMC IC modeling

November 17, 2009

Goichi YokomizoSemiconductor Technology Academic Research Center

(STARC)

Shinichiro MitaniHitachi, Ltd.

IEC SC47A/WG2 JPNCOsami Wada47A/826/DTR

IEC/TR 62433-2-1,Ed.1: EMC IC modelling Part 2-1: Theory of (2009-10-23) black box modelling for conducted emission

2

Outline• Purpose• Definition of BBM• Basics of BBM

– BBM of 1-port linear circuit– BBM of N-port linear circuit

• Objective of BBM for EMC• ICEM-CE• BBM expression

– Extraction from design data– Extraction from measurement– Features of BBM expression

• Application example• Summary• Appendix

3

Purpose• For EMC analysis of the electronic equipment using the

IC, it is necessary to model EMC properties of the whole IC compactly.

• A model called ICEM-CE is used, and it was proposed as IEC standard. (IEC 62433-2 (2008-10) Ed. 1.0 English)

• When a model is built by each element in correspondence with the design data of the IC, the problem of the scalewould occur if it were applied to a large-scale IC.

• It is convenient if there is modeling to be able to just use the measurement data with the pins of the IC.

• The following Black box modeling has been studied.

Circulation Date: 2009-08-28Closing Date: 2009-10-23 APPROVED

IEC/TR 62433-2-1,Ed.1: EMC IC modelling Part 2-1: Theory of black box modelling for conducted emission

4

Definition of BBM

• Black box model (BBM) is expressed with an equivalent circuit to see the inside from the external terminals of the circuit.

• The characteristics of a BBM observed from outside is the same (equivalent) as the original circuit, but the structure of the BBM is different from the original one. Then it is not sure whether an internal node of the BBM exists in the actual circuit or not.

Black box model (BBM) supplies

one “Possible” and “Easy” way of Implementation of ICEM-CE,

with keeping internal IPs “Not Open”.

Good for “Data exchange” !

5

ICEM-CE is now being extended to express internal structures (blocks) for practical representation of packaged integrated circuits and SIP.

New Framework of ICEM-CE Modeling

6

Basics of BBM• Circuit elements: A smallest unit of circuit expression is called

an element. For example, it is a resister, a capacitor, or an inductor. An element has two terminals, and its characteristic is defined with the voltage between the terminals vs. the currentthrough the element (Ohm's law). But it is not asked its further internal structure. In other words, it is a BBM.

• Linear circuit: By a circuit theory (Thevenin’s theorem or Norton’s theorem), a linear circuit is able to be converted to an equivalent circuit which has specified nodes of the original circuit as external terminals. (See the next slide.)

• Non-linear circuit: It is not guaranteed that it can be converted into an equivalent BBM circuit. Although a BBM circuit can be made and used by limiting its usage, for example an IBIS modelis a BBM of a non-linear circuit.

7

Thevenin’s Theorem

LinearCircuit

Y I

Admittance

EquivalentCurrent Source

Z

V

Norton’s Theorem

Impedance

EquivalentVoltage Source

BBM of 1-port linear circuit

with internalV.S. or C.S.

“Short Circuit”

“Open Circuit”

8

BBM of N-port linear circuit• Thevenin’s theorem or Norton’s theorem is equivalent expression

for a 1-port circuit. It is necessary to expand this in a multiport circuit.

• For the BBM expression of a multiport circuit, it is common to express with a voltage vector of the ports (V), a current vector of the ports (I), and a circuit matrix (impedance matrix Z, admittance matrix Y, etc.) which expresses the relations between V and I.

• The multiport expression using admittance expression (YV = I) is used in this presentation. It is used widely in circuit simulators based on the nodal analysis method like SPICE.

9

LinearCircuit

Y J1

Basic equation：YV = I + JY: Admittance matrix from PortsJ: Equivalent Current SourceV: Port VoltageI: Port Current

V1・・・

Port1

・・・

PortN

JN VN

I1

IN

BBM of N-port linear circuit

with internalV.S. or C.S.

10

Y

V1J1

・・・

VNJN

IN

Y1NVN

YN(N-1)VN-1

Y12V2

YN1V1

Y11

YNN

・・・

・・・

・・・

I1

BBM of N-port linear circuit

11

Objective of BBM for EMC

• Integrated circuit (IC) and its modeling board

Power/ ground pins

Integrated circuit

Zload

Zload

Zload

Zload

Out

put p

insInput pins

Modeling board

Input signal vector

Z PG

Z PG

Z PG

Z PG

– To activate the IC properly, the IC has to be provided with power supplies, a set of input signals or an input signal vector, and appropriate loads for output pins.

– The modeling board provides minimum requirements for the activation. It supplies power, and input signals to the IC, and it gives typical loads for the output pins. And power/ ground pins of the same category are connected to each other in the modelingboard resulting in one terminal for each category of the power/ ground supply at the interface of the modeling board.

input

loads

power

GND5V 3V

12

• Internal structure of IC part

Input circuits

Input pins

Internal circuits

Output circuits

Power/ ground pins

Out

put p

ins

Power/ ground network

･･･ ･･･ ･･･

Objective of BBM for EMC

or PDN

PDN: Power Distribution Networkor Passive Distribution Network (in ICEM-CE)

13

ICEM-CE• ICEM-CE is a macro model that approximates conducted

emission behaviour of an IC using two types of components, Internal Activity (IA) and Passive Distribution Network (PDN) . These two types of components are connected through Internal Terminals (ITs).

IA IA

Internal terminals

･･･

Passive distribution network (PDN)

External terminals

Internal activity (IA)

14

ICEM-CE• The IAs represent noise sources that originate in switching

of active devices within the IC. And the PDN represents noise propagation characteristics from the internal terminals to the External Terminals (ETs).

IA IA

Internal terminals

･･･

Passive distribution network (PDN)

External terminals

Internal activity (IA)

15

ICEM-CE• ICEM-CE model for the example of an IC and its modeling board

Power/ ground terminals

Input circuits

Power/ ground terminals

Internal circuits

Power/ ground terminals

Output circuits

Power/ ground network

Input signal vector

Zload

Zload

Zload

Zload

Z P G Z P G Z P G Z P G

IA part

PDN part

･･･ ･･･ ･･･

IC PDN part

Board PDN part

PDN in ICEM-CE

16

ICEM-CE• ICEM-CE model for the example of an IC and its modeling board

– The IA part includes input vector generators and output loads on the modeling board.

Power/ ground terminals

Input circuits

Power/ ground terminals

Internal circuits

Power/ ground terminals

Output circuits

Input signal vector

Zload

Zload

Zload

Zload

IA part

･･･ ･･･ ･･･

17

ICEM-CE• ICEM-CE model for the example of an IC and its modeling board

– The PDN part consists of the IC PDN part and Board PDNpart. The IC PDN part consists of the power/ ground network of the die and the package of the IC.

Power/ ground networkZ P G Z P G Z P G Z P G

PDN part

･･･ ･･･ ･･･

IC PDN part

Board PDN part

18

ICEM-CE

• Integrated circuit and its modeling board using ICEM-CE – Computational complexity becomes enormous for SoC.– Extraction of IA, PDN from measurement is not simple.

PDN of IC

IA IA IA IA IA IA

External terminals

Internal terminals･･･ ･･･ ･･･

PDN of BoardExternal terminals

We should know all the internal structure.

19

BBM expression• Structure of BBM

– constructed in the combination of the ICEM-CE components.– regarded as one of the expression of ICEM-CE.

Equivalent PDN[Y'ET ET]

IC Black box model

IA'1

IA'2

IA'n

Equivalent IAs

ET1 ET2 ETnET0

20

Extraction from design data• Initial equation using ICEM-CE modeling from design data

• Final equation using ICEM-CE modeling with BBM

ET

IT

ET

ITITETIT

ITETETET

IAI

VV

YYYY

'' ETETETET IAIVY

ETIT1

ITITITETETETETET' YYYYY

IAYYIA 1ITITITET'

21

Extraction from measurement• Setup for measurement of IA’

– Equivalent IAs can be obtained by measuring under the condition that all the external terminals are RF shorted to the reference terminal.

• Setup for measurement of Y’– Element of equivalent PDN can be

derived from the following equation.

A

ET1 ET2 ETn

AA

ET0

IC

A

ET1 ETj ETn

AA

Vj

ET0

IC

j

iiji

''

VIAI

Y

, at all 0 jiVj

iiji

''

VIAI

Y

, at all 0 jiV

22

BBM expression

Equivalent PDN[Y'ET ET]

IC Black box model

IA'1

IA'2

IA'n

Equivalent IAs

ET1 ET2 ETnET0

j

iiji

''

VIAI

Y

, at all 0 jiVj

iiji

''

VIAI

Y

, at all 0 jiV

'' ETETETET IAIVY

23

Features of BBM expression

• The number of IA components is equal to the number of the external ports.The number of PDN components is equal to square of the number of the external ports.– It can be expressed with one number of elements that

does not depend on complexity of the internal structure.• IA and PDN are expressed only by data observed at the

external ports.– Easy to take the agreement with measurement data.– Easy to make a model from measurement data.

• The methodology for implementation of BBMs into an application board is shown in Appendix.

“Benefit” of modeling based on Real Measurement : including all Parasitics

24

Application example• The ICEM-CE model includes the IC, PCB, and power

source models.

IC modelPCB modelPower modelnode (1)

node (2)node (3)

node (1)node (1)

ref.

IA_coreIA_IOs

R10.64

R651.7

R200.01

R40.044

L25.66 n

L33.56 n

L30145 p

L12 n

C26.2 n

C1851 p

C10745 p

IC modelPCB modelPower modelnode (1)

node (2)node (3)

node (1)node (1)

ref.

IA_coreIA_IOs

R10.64

R651.7

R200.01

R40.044

L25.66 n

L33.56 n

L30145 p

L12 n

C26.2 n

C1851 p

C10745 p

IEC 62433-2, Ed.1Annex D(informative)

25

Application example

0.0

0.2

0.4

0.6

0.8

1.01.2

1.4

1.6

1.8

2.0

0.E+00 1.E-07 2.E-07 3.E-07 4.E-07time (s)

Curr

ent (

A)

IA_coreIA_I/Os

• The IC is operated under a 10 MHz clock, and the operational mode needs four machine cycles. Therefore, the cycle time of the operation is 400 ns.

• The Waveforms of the IAs:

26

Application example• The initial IC model using ICEM-CE

• With BBM– The admittance matrix, voltage vector and current vector

become simple complex numbers.

I/Os

core

1

3

2

1

11

3651

365

21

211

21

1365

121

1365

121

00

IAIA

I

VVV

CjLjRLjRCjLjRLjR

LjRLjRLjRLjR

IAI

VV

YYYY ET

IT

ET

IT ITET IT

IT ETET ET

ET IT1

IT ITIT ETET ETET ET' YYYYY

I/Os

core1IT ITIT ET'

IAIA

YYIA

'' 1ET ET IAVY

27

Application example

• Spectrum of equivalent IA:

-100

-90

-80

-70

-60

-50

-40

-30

-20

-10

0

1.0E+06 1.0E+07 1.0E+08 1.0E+09Frequency (Hz)

Cur

rent

(dB

A)

-3.14

0

3.14

Ang

le (R

ad.)

Core currentI/Os currentCore current angleI/Os current angle

-100

-90

-80

-70

-60

-50

-40

-30

-20

-10

0

1.0E+06 1.0E+07 1.0E+08 1.0E+09Frequency (Hz)

Cur

rent

(dB

A)

-3.14

0

3.14

Ang

le (R

ad.)

CurrentAngle

(a) IA_core and IA_I/Os (b) Equivalent IA

28

Application example

• The ICEM-CE model with BBM:

IC modelPCB modelPower modelnode (1)node (1)node (1)

ref.

Y’ETET

R200.01

R40.044

L30145 p

L12 n

C10745 p

IC modelPCB modelPower modelnode (1)node (1)node (1)

ref.

R200.01

R40.044

L30145 p

L12 n

C10745 p

IA’

29

Application example• Noise voltage and noise current

'' 11 IAYYYV

PowerPCBET ET

1VYYII PowerPCBPowerPCB

-180

-160

-140

-120

-100

-80

-60

-40

-20

0

1.E+06 1.E+07 1.E+08 1.E+09Frequency (Hz)

Noi

se v

olta

ge (d

BV

), cu

rren

t (dB

A)

Noise voltageNoise current

30

Summary

• Black box modeling for EMC analysis is proposed.• The number of elements does not depend on IC internal

structure, and is fixed with the number of the external ports.– Applicable to the EMC modeling of a large-scale IC

core including SoC.• It can be modeled only by the characteristics at the

external ports.– Easy to take the agreement with measurement data.– Easy to make a model from measurement data.

31

IEC 62132-1 : 5. Modelling approaches

5.1 GeneralCE (Conducted Emission), RE (Radiated Emission)CI (Conducted Immunity), RI (Radiated Immunity)

5.2 Black box modelling approach• impedance (Z) matrix• admittance (Y) matrix• fundamental (F) matrix• scattering (S) matrix

5.3 Equivalent circuit modelling approach

LinearCircuit ・

・・

Port 1

Port N

AnalIA - AnalIA +

ZPack

ZDie

Core IA

S

AnalIA

Anal IAS

CoreIA

PDN

Kic2122 = 0.49LicVcc21 = 3.98nHLiCVss22 = 3.98nH

Kic5253 = 0.49LicVcc52 = 3.98nHLicVss53 = 3.98nH

KicAVccGNd = 0.41LicAVcc = 3.98nHLicGnd = 3.98nH

RicVcc211.43

RicVcc520.79

RicVss220.85

RicVss530.62

RicGnd0.47

RicAVcc1.66

CicVcc3.15nF

CicAVcc388pF

VssCorePDN2

VccCorePDN2

VssAnalPDNVccAnalPDN

VssCorePDN1

VccCorePDN1

Core IA -CoreIA +

Vcc

V SS

Chip

Package

V CL

AV cc (1) (10 )

(4)

(7)

5V 5V

3V

R A2.7

R ], L[nH ], C[nF ]

0 .37C A

L A5.4

LV4.2 L CL

3.9R CL

C CL

R IO

C IO

1.05

1.53.8

3.4

86R VR

L S3.1

LPCB2

ICEM-CE

LECCS

BBM

32

Appendix• Configuration of the application board

– The application board contains two ICs, IC-A and IC-B.– The board receives power supplies from the outside environment

through terminal group C.

IC-A[Y'A] [VA] = [IA]+[IA'A]

Terminal group A

IC-B[Y'B] [VB] = [IB]+[IA'B]

Terminal group B

Application board, [YAPP]

Terminal group CZ P

G

Z PG

Z PG

Z PG

Power supplies

33

Equivalent PDN[Y'A]

IC-A Black box model

IA'1

IA'2

IA'n

Equivalent IAsETA1 ETA2 ETAnETA0

Equivalent PDN[Y'B]

IC-B Black box model

IA'1

IA'2

IA'n

Equivalent IAs

Application board model

Equivalent PDN

[YAPP]Z P

G

Z PG

Z PG

Z PG [YPS PS]

ETB1 ETB2 ETBnETB0

Appendix• Setup for simulation of the application board

34

Appendix• BBM for IC-A and IC-B are

• The relationship between [VC] and [IC] is

• The whole application board is

• Adding these equations

AAAA '' IAIVY BBBB '' IAIVY

C

B

A

C

B

A

C CB C AC

C BB B AB

CA BA A A

III

VVV

YYYYYYYYY

CCPS PS IVY

0''

''

B

A

C

B

A

PS PSC CB CA C

C B BB BA B

CA BA AAA

IAIA

VVV

YYYYYYYYYYYY

35

Appendix• [VA], [VB] and [VC] can be derived

• [IA], [IB] and [IC] can be derived

0''

''

B

A1

PS PSC CB CA C

C B BB BA B

CA BA AAA

C

B

A

IAIA

YYYYYYYYYYYY

VVV

0''

''

B

A1

PS PSC CB CA C

C B BB BA B

CA BA AAA

C CB CA C

C BB BA B

CA BA AA

IAIA

YYYYYYYYYYYY

YYYYYYYYY

C

B

A

C CB CA C

C BB BA B

CA BA AA

C

B

A

VVV

YYYYYYYYY

III