Upload
lemien
View
234
Download
6
Embed Size (px)
Citation preview
Challenges and solutions for
Impedance measurements
Gustaaf Sutorius
Application
Engineer
1
2
Introduction & Objectives for today
Challenges and solutions for Impedance measurements
3
Challenges and solutions for Impedance measurements
Agenda
1. Introduction
2. Impedance Basics & Measurement Methods
3. LCR Meters
4. Impedance Analyzers
5. Accessories/test-fixtures
6. Vector Network Analyzers
• E5061B VNA as Impedance Analyzer
7. Reference Documents + Q&A
4
Agenda
1. Introduction
2. Impedance Basics & Measurement Methods
3. LCR Meters
4. Impedance Analyzers
5. Accessories/test-fixtures
6. Vector Network Analyzers
• E5061B VNA as Impedance Analyzer
7. Reference Documents + Q&A
5
Objectives
• Review Impedance Measurement Methods
• LCR meter vs Impedance analyzer vs Network
Analyzer
• Review E5061B Network Analyzer/Impedance
Analyzer.
• “It’s also the test-fixture”
6
Impedance Measurement Applications
www.agilent.com/find/impedance
Auto-balancing Bridge
Transformer
Measurements
Capacitor
Measurements
Inductor
Measurements
Resistor
Measurements
Material
Measurements
On-wafer C-V
Measurements
Resonator
Measurements
In-circuit
Tests
MOS FET
Measurements Diode
Measurements
Battery
Measurements
RF I-V LCR Meters Impedance Analyzers (ZA) Wide Variety of Test Fixtures
Cable
Measurements
7
Solutions for Measuring Impedance
‘60
‘70
‘80
‘90
‘00
‘10
Low-Cost
LCR Meter ZA RF ZA
High-Performance
LCR Meter Capacitance
Meter RF LCR Meter
4270A
E4991A
4291A/B
E4980A
E4982A
4294A
4263A/B 4284A/85A
4278A
4192A
4194A
4260A
4271A
4261A
4274A/75A
4262A
4272A/73A
4268A/88A
E4981A
4286A
4287A
4191A
4276A/77A
Installed Base of Legacy Products E4980AL
8
Agenda
1. Introduction
2. Impedance Basics & Measurement Methods
3. LCR Meters
4. Impedance Analyzers
5. Accessories/test-fixtures
6. Vector Network Analyzers
• E5061B VNA as Impedance Analyzer
7. Reference Documents + Q&A
9
Impedance
Z = R + jX (rectangular-coord)
Z = |Z| (polar form)
R = |Z| cos
X = |Z| sin
|Z| = R2 + X2
Imaginary axis
X
R Real axis
|Z|
Z (R,
X)
= tan-1(X/R)
Unit of impedance: ohm ()
Z: Total opposition a device or circuit offers to the flow of AC
+j
10
Series and Parallel Combinations
Real and imaginary
components are
connected in series
Z = R + jX
(Impedance is easier to express)
Y = G + jB
(Admittance is easier)
R
jX
G
jB
R jX
(Impedance is too complex)
R + jX
jRX =
RX2 R2X + j Z =
R2 + X2 R2 + X2
Real and imaginary
components are
connected in parallel
Unit of admittance: Siemens (S) conductance, G and the susceptance, B
11
Inductive and Capacitive Reactance
L (Inductance) C (Capacitance)
XL= 2fL = L C
XC = 2fC
1 =
1
R jXL R -jXC
Q = quality factor
(a) Inductive vector
on impedance plane
(b) Capacitive vector
on impedance plane
XL
R =
-XC
R =
= tan
Z jXL
R
Z -jXC
R
tan
= D dissipation factor = 1
Q =
: Angular frequency (= 2f)
12
Parasitics
• No real components are purely resistive or reactive
Capacitor Equivalent Circuit
• Every component is a combination of R, C and L elements
• The unwanted elements are called parasitics
Unwanted
R and L of
leads
Unwanted R and C
of dielectric
Intrinsic C
13
Series and Parallel Models
High-Impedance Device
(Small C, Large L; |Z| 10 k)
Capacitor Equivalent
Circuit
Series
Model
Parallel
Model R
s
C
s
R
p
C
p Low-Impedance Device
(Large C, Small L; |Z| 10 )
14
Equivalent circuit models of components
15
Relationship between Series and Parallel mode
16
Component Dependency Factors
• Test signal frequency
• Test signal level
• DC voltage and current bias
• Environment
• Measurement conditions that determine the measured
impedance value
• Effects depend on component materials and manufacturing
processes
• Four major factors:
17
X versus Test Signal Frequency
|X|
Frequency ()
XL = L
XC =
1
C
Capacitor
Resonant
Frequency
XC = XL
L C
18
Impedance versus Frequency
C
1
L
fs
|Z|
Example Capacitor Resonance
19
C versus Test Signal Level
AC Test Signal level (Vac)
Low K
Mid K
High K
C
AC voltage dependency of ceramic SMD capacitors
for various values of dielectric constant (K)
Capacitance change due to
AC voltage dependence of
K value
20
C versus DC Voltage Bias
Type I
C0G or NPO (Low K)
0
Type II
X7R,Y5V, or Z5U (High K)
DC bias voltage
C
DC bias voltage dependency of
type I and II SMD capacitors
Capacitance change due to
DC voltage dependence of K value
21
L versus DC Current Bias
L
0
DC bias current
DC bias current dependency of
cored inductors
Inductance roll-off due to
magnetic saturation of inductor core
22
C versus Temperature
C
0
High K
Mid K
Temperature (C)
|
25
Temperature dependency of ceramic
capacitors for different K values
K: Dielectric Constant
23
Agenda
1. Introduction
2. Impedance Basics & Measurement Methods
3. LCR Meters
4. Impedance Analyzers
5. Accessories/test-fixtures
6. Vector Network Analyzers
• E5061B VNA as Impedance Analyzer
7. Reference Documents + Q&A
24
(1) Auto-Balancing Bridge method
V
-
+
2
V 1
DUT
V2 =
Z = V1
Ir =
V1 Rr
V2
HIGH LOW
R r
I r
Virtual ground (driven at 0 V)
I I = I r
- Ir Rr
-
Signal
Source
Measurement Principle
25
(2) RF I-V method
Zx= = ( - 1) V R Vv
I 2 Vi
Vi
Vv
R/2
R DUT Voltage
detection
Current detection
Test Head (High-Impedance type)
Z
x V
I
R
R = 50
Signal
Source
Measurement Principle
As V = Vv – Vi and I = 2Vi /R
26
(3) Network Analysis method
DUT
Vr
Vr
VINC
ZX - Z0 = = ZX +
Z0
VINC
ZX
V
Incident
Signal
Reflected
Signal
Directional Bridge
or Coupler
OSC
V VINC Vr
Zo: 50 or 75
Measurement Principle
27
Summary of Measurement Methods
Method Frequency
Range
Impedance
Range
Terminal
Connections
# of
Ports
1 m Z 100 M
(10% acc)
0.2 Z 20 k
(10% acc)
Z Z0 f 300 kHz
1 MHz f 3 GHz
20 f 110 MHz
Network
Analysis
RF I-V
Auto-
Balancing
Bridge
7 mm, N-type
7 mm
4-terminal pair,
BNC
N 1
1
1
Impedance (
)
Frequency (Hz)
Network An.
Auto-Balancing Bridge
RF I-V
28
Network Analysis
RF I-V
Measurement Method Agilent Product Frequency Range
Auto-Balancing
Bridge
4263B LCR Meter
E4981A C Meter
E4980A Precision LCR Meter
4285A Precision LCR Meter
4294A Precision Impedance Analyzer
100 Hz to 100 kHz spot
120 Hz/1 kHz/1 MHz spot
20 Hz to 2 MHz
75 kHz to 30 MHz
40 Hz to 110 MHz
E4982A RF LCR Meter
E4991A Impedance/Material Analyzer
1 MHz to 3 GHz
1 MHz to 3 GHz
5 Hz to 20 GHz ENA Series
Vector Network Analyzers
300 kHz to 1.1 THz PNA Series
uW Vector Network Analyzers
Measurement Methods and Agilent products
29
Impedance Measurement Methods and Instrument selection
1) Frequency
2) DUT impedance
3) Required measurement accuracy
4) Electrical test conditions
5) Measurement parameters
6) Physical characteristics of DUT
These determine the most
suitable method
These determine the proper
instrument and test fixture
30
Agenda
1. Introduction
2. Impedance Basics & Measurement Methods
3. LCR Meters
4. Impedance Analyzers
5. Accessories/test-fixtures
6. Vector Network Analyzers
• E5061B VNA as Impedance Analyzer
7. Reference Documents + Q&A
31
Historical Product Overview Over 40 Years Experience
‘60
‘70
‘80
‘90
‘00
‘10
Low-Cost
LCR Meter ZA RF ZA
High-Performance
LCR Meter Capacitance
Meter RF LCR Meter
4270A
E4991A
4291A/B
E4980A
E4982A
4294A
4263A/B 4284A/85A
4278A
4192A
4194A
4260A
4271A
4261A
4274A/75A
4262A
4272A/73A
4268A/88A
E4981A
4286A
4287A
4191A
4276A/77A
ZA LCR
Installed Base of Legacy Products E4980AL
32
Current Product Portfolio for Impedance
4294A
Precision impedance analyzer
E4980A
precision LCR meter
4263B
LCR meter E5071C
ENA network analyzer
E4991A
RF impedance/material analyzer
E4981A
Capacitance meter
LCR meter Impedance Analyzer Network Analyzer
E4982A
LCR meter
E5061B
ENA-L network analyzer
E4980AL
precision LCR meter
www.agilent.com/find/impedance
33
Product Overview LCR Meters & Impedance Analyzers & Network Analyzers
LCR Meters & Impedance Analyzers Network Analyzers
Specialized to measure LCR & impedance
High impedance accuracy
Wide impedance measurement range
Main target application:
• Capacitors, inductors, resonators
• Materials
• Semiconductor
• In-circuit (4294A w/42941A)
Measure S-parameter, also can be used for
impedance measurement
Higher Frequency range
Main target application:
• Filters, Antennas
• DC-DC converters
• Amplifiers, Mixers
34
Product Overview LCR Meters & Impedance Analyzers Product Portfolio
Main
Usage R
&D
La
b
Genera
l P
urp
ose
Hig
h V
olu
me
Ma
nu
factu
rin
g
$10k
Unit Price [$]
$20k $30k $40k $50k
4263B
LCR meter
100 Hz – 100 kHz
E4981A
Capacitance meter
120 Hz, 1 kHz, 1 MHz
E4982A
RF LCR meter
1 MHz – 3 GHz
4339B
High-R meter
4285A
Precision LCR meter
75 kHz – 30 MHz
4294A
Precision impedance analyzer
40 Hz – 110 MHz
E4991A
RF impedance/material analyzer
1 MHz – 3 GHz
+ Wide Variety of
Accessories
ZA
LCR
E4980AL E4980A Precison LCR meter
20 Hz – 300 kHz/500 kHz/1 MHz/2 MHz
35
LCR Meters
4294A
precision impedance analyzer
E4991A
RF impedance/material analyzer
LCR meter Impedance Analyzer Network Analyzer
E5071C
ENA network analyzer
E5061B
ENA-L network analyzer
E4980A
precision LCR meter
4263B
LCR meter
E4981A
capacitance meter
E4982A
LCR meter
4339B
high-R meter
E4980AL
precision LCR meter
36
LCR Meters What Is LCR & Impedance Measurement?
Capacitance
(Cs, Cp)
Inductance
(Ls, Lp)
Phase ()
Z
R
X
Reactance (X)
Resistance (R)
Measure Z, then calculate LCR value…
δ
D, Q
E4980A
(Cp-D measurement)
37
LCR Meters Overview
Frequency (Hz)
10 100 1k 10k 100k 1M 10M 100M 1G 10G
20 Hz – 2 MHz
100 Hz – 100 kHz
1 MHz – 3 GHz
120 Hz, 1 kHz, 1 MHz
E4980A precision LCR meter
4263B LCR meter
E4981A capacitance meter
E4982A LCR meter
• Spot frequency measurement
• Numeric only display
• Low cost
• High speed
• Application specific E4982A Measurement Display E4980A Measurement Display
20 Hz – 300 kHz/500 kHz/1 MHz E4980AL precision LCR meter
38
LCR Meters List Sweep : the poor mans Impedance Analyzer”
• Instrument: E4980A
• DUT: 100 nF ceramic capacitor & 100 uH chip inductor
• Key Word:
– Adapter Compensation
– ALC function
– List Sweep
39
LCR Meters Key Products Overview
E4982A LCR Meter 1 MHz to 3 GHz
• An industrial standard in RF impedance/material measurements up to 3 GHz
• Target applications – passive components
• Target customers – manufacturing
• Migration opportunities – 4286A, 4287A
E4980AL/A Precision LCR Meter 20 Hz to 300 kHz, 500 kHz, 1 MHz / 2 MHz
• A new standard for low-frequency impedance measurements up to 2 MHz
• Target applications – passive components, semiconductors, MEMS, materials
• Target customers – R&D, manufacturing, QA, incoming inspection
• Migration opportunities – 4279A, 4284A
E4981A Capacitance Meter 120/1k/1MHz
• A new standard for ceramic capacitor (C) production tests
• Target applications – capacitors
• Target customers – manufacturing
• Migration opportunities – 4278A, 4268A, 4288A
4263B Low-Cost LCR Meter 100/120/1k/10k/100kHz (20kHz option)
• Cost effective solution for low-frequency impedance measurements up to 100 kHz
• Target applications – passive components, transformers, electrolytic capacitors
• Target customers – R&D, manufacturing
• Migration opportunities – 4263A
40
Agenda
1. Introduction
2. Impedance Basics & Measurement Methods
3. LCR Meters
4. Impedance Analyzers
5. Accessories/test-fixtures
6. Vector Network Analyzers
• E5061B VNA as Impedance Analyzer
7. Reference Documents + Q&A
41
Impedance Analyzers
4294A
precision impedance analyzer
E4991A
RF impedance/material analyzer
LCR meter Impedance Analyzer Network Analyzer
E5071C
ENA network analyzer
E5061B
ENA-L network analyzer
E4980A
precision LCR meter
4263B
LCR meter
E4981A
capacitance meter
E4982A
LCR meter
4339B
high-R meter
E4980AL
precision LCR meter
42
• No real components are purely resistive or reactive
Capacitor Equivalent Circuit
• Every component is a combination of R, C and L elements
• The unwanted elements are called parasitics
Unwanted
R and L of
leads
Unwanted R and C
of dielectric
Intrinsic C
Impedance Analyzers Parasitics
43
Impedance Analyzers X versus Test Signal Frequency
Frequency ()
XL = L
XC =
1
C
Resonant
Frequency
C L Im
ped
an
ce |
X|
44
Impedance Analyzers Example Capacitor Resonance
Impedance versus Frequency
C
1
L
|Z|
45
Impedance Analyzers Overview
Frequency (Hz)
10 100 1k 10k 100k 1M 10M 100M 1G 10G
• Sweeps parameter, displays graphics
– Frequency
– DC Bias
– AC level
• Use model
– Frequency characteristics analysis
– Resonant analysis
– Circuit modeling
40 Hz – 110 MHz
1 MHz – 3 GHz
4294A precision impedance analyzer
E4991A RF impedance/material analyzer
46
Impedance Analyzers 4294A Impedance Analyzer
Frequency range: 40 Hz ~ 110 MHz
Basic measurement accuracy: 0.08 %
Key numbers…
A
L
Ca
R
B
Ca
L R
C
Ca
L
R
L Ca R
Cb
L Ca R
E D
EQV R 38.6347 mΩ EQV L 2.19795 nH
EQV Ca 82.1028 nF
EQV Cb F
C
DC LVL
C
AC LVL
Z-Q
Frequency
Frequency Sweep DC Bias Sweep AC Level Sweep
Versatile Analysis Functions
Equivalent Circuit Calculation
47
– Frequency dependency of the capacitor
– Influence of the residual inductance
– Resonant frequency
– Equivalent circuit simulation
– Limit Test
Impedance Analyzers allow to measure:
48
Impedance Analyzers Key Products Overview
E4991A RF Impedance/Material Analyzer 1 MHz to 3 GHz
• An industrial standard in RF impedance/material measurements
• Target applications – passive components, semiconductors, materials
• For – R&D, QA, incoming inspection
• Replaces 4291A
4294A Precision Impedance Analyzer 40 Hz to 110 MHz
• An industrial standard in mid-freq. impedance measurements
• Target applications – passive components, semiconductors, materials, in-circuit
• For– R&D, QA, incoming inspection
• Replaces – 4192A, 4194A
49
Summary: Impedance Analyzer versus LCR Meter
Impedance Analyzer LCR Meter
• Full measurement conditions
• Freq/Osc/DC bias sweep
• Wide frequency coverage
• Versatile analysis capability
• Markers, List Sweep, Limit
Test, EQT CKT, IBASIC, LAN
• Graphic display
• Measurement traces
Suitable for deep evaluation or
multipurpose use
• Limited measurement conditions
• No or limited sweep
• Spot/multiple frequencies
• Limited analysis capability
• GO/NO GO testing
• Numerical display
• Only numbers displayed
Suitable for simple testing
50
Summary:
Frequency range Impedance Analyzer & LCR Meter
100 1k 10k 100k 1M 10M 100M 1G (Hz)
Low-cost
LCR 4263B 0.1%
4285A
E4982A
Precision
LCR
E4980A 0.05%
0.1%
1%
4294A Impedance
Analyzer 0.08%
40 Hz
3 GHz
110 MHz
100 kHz
20 Hz
30 MHz 75 kHz
1 MHz
100 Hz
E4991A 0.8% 3 GHz 1 MHz
2 MHz
51
Agenda
1. Introduction
2. Impedance Basics & Measurement Methods
3. LCR Meters
4. Impedance Analyzers
5. Accessories/test-fixtures
6. Vector Network Analyzers
• E5061B VNA as Impedance Analyzer
7. Reference Documents + Q&A
52
Accessories Introduction
• MUST be used to connect DUTs
– Fixtures, Probes
– Test leads
– DC bias
– Cal std…
• Benefits of Agilent Accessories
– Minimum residual error for better accuracy
– Clearly defined error compensation for
error correction
– Strict measurement specifications
53
Accessories Wide Variety of Fixtures to Cover Various Applications
54
Accessories Top 3 Fixtures for Auto balancing Bridge Instruments
16334A SMD/chip Tweezers
Frequency: ≤15 MHz
Maximum dc bias: ±42 V
Applicable SMD size: Minimum 1.6 (L) ´ 0.8 (W) mm
16089B Medium Kelvin Clip Leads
Clip type: Kelvin alligator clips (small)
Frequency: 5 Hz to 100 kHz
Maximum dc bias: ±42 V peak
Cable length: 0.94 m
16047A Test Fixture (Axial and Radial)
Frequency: ≤13 MHz
Maximum dc bias: ±35 V
Four-terminal (Kelvin) contacts
55
Agenda
1. Introduction
2. Impedance Basics & Measurement Methods
3. LCR Meters
4. Impedance Analyzers
5. Accessories/test-fixtures
6. Vector Network Analyzers
E5061B VNA as Impedance Analyzer
7. Reference Documents + Q&A
56
Vector Network Analyzers for measuring Impedance one of the 3 Key Impedance Measurement Methods
4294A
Precision impedance analyzer
E4980A
precision LCR meter
4263B
LCR meter E5071C
ENA Network Analyzer
E5061A/62A
ENA-L Network Analyzer
E4991A
RF impedance/material analyzer
E4981A
Capacitance meter
LCR meter Impedance Analyzer Network Analyzer
4287A
RF LCR meter
E5061B
ENA LF Network Analyzer
• High accuracy and wide impedance range
• HF and RF
• Variety of fixture selections
• Lower frequency range is limited by the transformer
used in the test head
RF I-V
• Covers highest
frequencies
• High accuracy
around the
characteristic
impedance (Z0)
• Narrow impedance
measurement range
• Low accuracy in Q
(D) measurement
Network Analysis
Auto-Balancing Bridge
• Wide frequency coverage (LF to HF)
• High accuracy over a wide impedance range
• Variety of fixture selections
• Higher frequency range not available
57
Imp
ed
an
ce
(Ω
)
Frequency (Hz)
Auto-Balancing Bridge
Network Analysis Measurement Range Impedance Accuracy versus frequency
100M
10M
1M
100k
10k
1k
100
10
1
100m
10m
1m
10 100 1k 10k 100k 1M 10M 100M 1G 10G
RF I-V
Network Analysis
10% accuracy range for each measurement technique
4294A E4980A/AL 4263B E4981A
E4991A E4982A
E5061B E5071C
Note: PNA Network Analyzer
covers 300 kHz to 1.1 THz
58
Measurement Frequency Range Summary
Product
Type Purpose Frequency Range
Basic
Accuracy
Z Meas. Range
(10% Accy. Range) Model
Measurement
Method
Network
Analyzer
S-parameter/
Impedance 9 kHz/100 kHz – 20 GHz
N/A NA
E5071C Network
S-parameter/
Gain–phase/
Impedance
5 Hz – 3GHz E5061B Network
Impedance
Analyzer
High performance/
Multi function 1 MHz – 3 GHz 0.8 % 130 m – 20 kohm E4991A RF I-V
High performance/
Multi function 40 Hz – 110 MHz 0.08 % 25 m – 40 Mohm 4294A ABB
LCR Meter
Inductor
measurement 1 MHz – 3 GHz 0.8 % 140 m – 4.8 kohm E4982A RF I-V
High performance/
Multi function 20 Hz – 2 MHz 0.05 % 10 m – 100 Mohm E4980A ABB
Low cost/
Multi function
20 Hz – 300 kHz/500
kHz/1 MHz 0.05 % 10 m – 100 Mohm E4980AL ABB
Low cost/
Multi function
100 Hz/120 Hz/1 kHz/10
kHz/20 kHz/100 kHz 0.1 % 1 m – 100 Mohm 4263B ABB
Capacitance
Meter
Capacitor
measurement 120 Hz/1 kHz/1 MHz 0.07 % 0.001 p to 2 mF E4981A ABB
Note: PNA Network Analyzer covers 300 kHz to 1.1 THz
59
E5061B-3L5 LF-RF Network Analyzer
• 5 Hz to 3 GHz
• Wide dynamic range
• Built-in DC bias source (0 to ±40 Vdc, max 100 mAdc)
• A S-parameter test port (5 Hz to 3 GHz, 50 Ω)
• B Gain-phase test port (5 Hz to 30 MHz, Zin=1 MΩ / 50 Ω switchable)
• C Impedance analysis function (Option 005)
Gain-phase test port
S-parameter test port
R T
Zin
ATT
R1
T1
R2
T2
R
Zin
ATT
T
LF OUT
Port-1 Port-2
DC bias source
E5061B-3L5
Gain-phase test port (5 Hz to 30 MHz)
S-parameter test port (5 Hz to 3 GHz)
Zin=1 MΩ #1 or 50 ohm
ATT=20 dB or 0 dB
60
6 A: E5061B as VNA for S-Parameters (5Hz to 3GHz) - Filter
- Antenna
- Amplifier
- Cable
61
6 B: E5061B as gain-phase analyzer (5 Hz – 30 MHz)
Detail: E5061B’s R and T receiver ports are semi-floated This eliminates the measurement error associated with the source-to-receiver test
cable ground loop. As receivers are semi-floated with the impedance |Zg|, which is
about 30 Ω in the lowfrequency range below 100 kHz. Similarly to the case of
using the magnetic core, we can intuitively understand that the shield current is
blocked with the impedance |Zg|. More details in appnote
http://cp.literature.agilent.com/litweb/pdf/5990-5578EN.pdf
Freq
DUT’s true attenuation
Measured attenuation Easy & accurate solution for
• High attenuation DUTs (<-80 dB)
• milliohm-|Z| of LF PDN components
|Zg| = about 30 Ω at low freq. range
Rc2 = 10 mΩ or several 10 mΩ
Common-mode noise
VT
VR
Rc2
Vo
AC current
T port
Zg
R port
LF OUT
V=Vc2
Va
Zg
VT = Vo + Vc2
= Vo + (Va/(Zg+Rc2)) x Rc2
= Vo, because Zg >> Rc2
Zsh
62
6 C: E5061B as Impedance Analyzer using Option E5061B-005 ZA firmware
• Fully supports basic functions of
impedance analyzer (ZA)
• Displays Z parameters
• Calibration + Fixture compensation
• Equivalent circuit analysis
• Covers variety of ZA applications
with multiple meas. techniques
Reflection
method
(for low to mid-Z)
Series-thru
method
(for mid to high-Z)
Shunt-thru
method
(for very low-Z)
Advantages of Z measurement with E5061B
NA plus ZA in one box
Milliohm Z-measurement
Very broad freq range
63
E5061B Impedance Measurement methods
Both test ports are available for impedance measurements
S-Parameter test port Gain-Phase test port
S-Parameter
5 Hz - 3 GHz
• Reflection
• Series-thru
• Shunt-thru
Gain-Phase
5 Hz - 30 MHz
• Series-thru
• Shunt-thru
Test port
Frequency range
Measurement
configurations
Port 1 Port 2 T LF OUT R
64
Reflection method
Z = 50 x ((1 + S11) / (1 - S11))
S-Parameter S11
VS VDUT
-50
-40
-30
-20
-10
0
1.E-01 1.E+00 1.E+01 1.E+02 1.E+03 1.E+04
VT/V
R (S
11
, S
21
, T
R)
[dB
]
Impedance [Ω]
0.1 1 10 100 1k 10k
50Ω
Vector voltage ratio relationship to impedance
Mid-Z
65
Series-thru method
Z = (50 x 2) x ((1 - S21) / S21)
S-Parameter
Gain-Phase
S21
T/R
V I
V I
Vector voltage ratio relationship to impedance
-50
-40
-30
-20
-10
0
1.E-01 1.E+00 1.E+01 1.E+02 1.E+03 1.E+04
VT/V
R (S
11
, S
21
, T
R)
[dB
]
Impedance [Ω]
0.1 1 10 100 1k 10k
Mid to High-Z
66
Shunt-thru method
Z = (50 / 2) x (S21 / (1 - S21))
S-Parameter
Gain-Phase
S21
T/R
VS VDUT
VS VDUT -50
-40
-30
-20
-10
0
1.E-01 1.E+00 1.E+01 1.E+02 1.E+03 1.E+04
VT/V
R (S
11
, S
21
, T
R)
[dB
]
Impedance [Ω]
0.1 1 10 100 1k 10k
Vector voltage ratio relationship to impedance
Low to Mid-Z
67
Measurement method & impedance range
Shunt-thru
Reflection
Series-thru
Applicable impedance range
Mid
Mid - High
Low - Mid
100 k 10 k 1 k 100 10 1 100 m 10 m 1 m
Configuration
Covers wide impedance range: mΩ to 100 kΩ
using 3 methods in combination
Impedance [ohm]
68
1.E-04
1.E-03
1.E-02
1.E-01
1.E+00
1.E+01
1.E+02
1.E+03
1.E+04
1.E+05
1.E+06
1.0E+00 1.0E+01 1.0E+02 1.0E+03 1.0E+04 1.0E+05 1.0E+06 1.0E+07 1.0E+08 1.0E+09 1.0E+10
10% measurement accuracy range
10 Hz 100 Hz 1 kHz 10 kHz 100 kHz 1 MHz 10 MHz 100 MHz 1 GHz
100 kΩ
10 kΩ
1 kΩ
100 Ω
10 Ω
1 Ω
100 mΩ
10 mΩ
1 mΩ
Imp
ed
ance
[O
hm
]
Frequency [Hz]
Port 1-2 Series
Port 1 Refl
Port 1-2 Shunt
S-Parameter test port
Supplemental performance data (SPD): It is not guaranteed by the product warranty.
Represents the value of a parameter that is most likely to occur; the expected mean or average.
69
1.E-04
1.E-03
1.E-02
1.E-01
1.E+00
1.E+01
1.E+02
1.E+03
1.E+04
1.E+05
1.E+06
1.0E+00 1.0E+01 1.0E+02 1.0E+03 1.0E+04 1.0E+05 1.0E+06 1.0E+07 1.0E+08 1.0E+09 1.0E+10
100 kΩ
10 kΩ
1 kΩ
100 Ω
10 Ω
1 Ω
100 mΩ
10 mΩ
1 mΩ
10% measurement accuracy range
10 Hz 100 Hz 1 kHz 10 kHz 100 kHz 1 MHz 10 MHz 100 MHz 1 GHz
Imp
ed
ance
[O
hm
]
Frequency [Hz]
GP Series
GP Shunt
Supplemental performance data (SPD): It is not guaranteed by the product warranty.
Represents the value of a parameter that is most likely to occur; the expected mean or average.
Gain-Phase test port
70
Measurement Methods Summary
Shunt-thru,
Low - Mid
Reflection,
Mid
Series-thru,
Mid - High
Test port & Method
S-Parameter (5 Hz - 3 GHz) Gain-Phase (5 Hz - 30 MHz)
Configuration &
Impedance range
(Splitter)
Port 1-2 Series GP Series (T: 50Ω, R: 1MΩ)
Port 1 Refl
Port 1-2 Shunt GP Shunt (T: 50Ω, R: 50Ω)
User
User User
7-mm
4-terminal pair
71
Test Fixtures (1)
16092A
16201A
16047E
Series-thru method
(Gain-Phase, T 50Ω, R 1MΩ)
5 Hz to 30 MHz
7 mm test fixture with
16201A
4-terminal pair test
fixture
Reflection method
(S-Parameter, Port 1)
5 Hz to 3 GHz
72
Test Fixtures (2) S-Parameter test port (Reflection method)
Test Fixtures available in actual FW: (None), 16191A, 16192A, 16193A, 16194A, 16196A/B/C, 16197A,
(User)
73
Test Fixtures (3) Gain-Phase test port (Series-thru method)
74
E5061B demonstration
Next pages contain slides for supporting discussion during
demonstration
75
Calibration and Fixture Compensation (1)
76
Calibration and Fixture Compensation (2)
Impedance calibration The impedance calibration executes the
open/short/load (and optional low-loss-C)
calibration in the impedance domain after
the measured S-parameter or gain-phase
ratio data is converted to impedance. [Cal] > Calibrate > Impedance Calibration
Fixture compensation - The open/short (and optional load)
compensation eliminates the fixture’s
residual impedance and stray admittance.
-The electrical length compensation
(selecting fixture type, or Z port extension)
eliminates the phase shift error that occurs
at 7 mm fixtures in the RF range. [Cal] > Fixture Compen > Compensate
Low-Loss Capacitor Calibration
When you measure Q, D, and ESR of RF
capacitors and RF inductors by using the
reflection method (with the 16201A), performing
the low-loss capacitor (LLC) calibration in
addition to the open/short/load improves the
accuracy at high frequencies over 1GHz. The
LLC provides a reference for calibration with
respect to the 90°-phase component of
impedance. LLC is available with 16195B CalKit.
Open/Short Compensation and Z Port
Extension
The recommended fixture compensation method
up to a few hundreds of MHz is the open/short
compensation.
For the measurement at higher frequencies over
a few hundreds of MHz, it is recommended to
perform the combination of the fixture electrical
length compensation and the open/short
compensation.
77
Z measurement with Network Analyzer (1)
Reflection method Middle Zdut
Zdut VT VR
50
50
50
50
50
S11=VT/VR
78
VNA Uncertainties Calculator
0
0.01
0.02
0.03
0.04
0.05
0 0.2 0.4 0.6 0.8 1
Un
cert
ain
ty (
Lin
ear)
Reflection Coefficient (Linear)
S11 Magnitude Accuracy
1MHz
S21 = S12 = 0; Cal power = -10 dBm; Meas power = -10 dBm
E5061B 3L5 (RSS) with 85033E Calibration Kit
IF Bandwidth = 1 Hz; Average Factor = 1
79
Impedance Uncertainty
0.0
5.0
10.0
15.0
20.0
25.0
30.0
1.0E-01 1.0E+00 1.0E+01 1.0E+02 1.0E+03 1.0E+04
Un
cert
ain
ty (
%)
Impedance (Ohm)
Reflection method: Impedance Uncertainty
80
Reflection method
16201A/001) +
16195B
1609x test fixture
• For middle Z-range
• Need Open/Short/Load cal
DUT
20*log |Z| [dB]
Ls [henry]
|Z| [ohm]
60 dB (=1 kohm)
1 kohm
10 uH
10 uH inductor measurement Test freq=100 kHz to 100 MHz Source= -10 dBm, IFBW=Auto / 100 Hz-limit
Configuration example
P/N 0699-2829 SMD 50 ohm
short
Open/Short/Load cal at fixture
81
Typical configuration examples for S-Parameter Reflection method (Low-Mid Z, up to 3 GHz)
- E5061B options
E5061B Network Analyzer
E5061B-3L5 LF-RF NA with DC bias
E5061B-005 Impedance analysis function for LF-RF NA (*1)
---------------------------------------------------------------
E5061B-1E5 High stability time base
E5061B-020 Standard hard disk drive
E5061B-810 Add key board
E5061B-820 Add mouse
- Adapter for connecting fixtures
16201A 7 mm terminal adapter kit
16201A-001(*2) 7 mm terminal adapter kit for E5061B
- 7 mm calibration kit
16195B (open/short/load + low-loss capacitor)
- 7 mm test fixtures
16092A (SMD & leaded component, 500 MHz)
(*1) E5061B-005 is not applicable to the E5061B RF NA option: 1x5 / 2x5 / 1x7 / 2x7.
(*2) Option 001 is the only option for the 16201A. Must choose this option when ordering the 16201A.
16092A
82
Reflection method: Home-made fixtures
SMA receptacle
DUT (soldered between
center pin and GND)
Copper foil (GND)
Cal devices
Open Short Load 50 ohm resistor
To Port-1
83
Z measurement with Network Analyzer (2)
Series-thru method Middle to large Zdut, no grounded DUT
VT VR
50
50
50
50
50 S21=VT/VR
Zdut
84
10% measurement accuracy range (E5061B, S-Parameter test
port)
1.E-04
1.E-03
1.E-02
1.E-01
1.E+00
1.E+01
1.E+02
1.E+03
1.E+04
1.E+05
1.E+00 1.E+01 1.E+02 1.E+03 1.E+04 1.E+05 1.E+06 1.E+07 1.E+08 1.E+09 1.E+10
Imp
ed
an
ce [
Oh
m]
Frequency [Hz]
100
kΩ
10 kΩ
1 kΩ
100 Ω
10 Ω
1 Ω
100
mΩ
10 mΩ
1 mΩ
10 Hz 100
Hz 1 kHz 10 kHz
100
kHz 1 MHz 10 MHz
100
MHz 1 GHz
E5061B (SPD) S-Parameter, Reflection
E5061B (SPD) S-Parameter, Series-thru
Definitions - Specification (Spec): Warranted performance. Specifications include guardbands to account for the expected statistical performance distribution,
measurement uncertainties, and changes in performance due to environmental conditions.
- Supplemental performance data (SPD): Represents the value of a parameter that is most likely to occur; the expected mean or average. It is not
guaranteed by the product warranty.
For more details about conditions for defining accuracy, please refer to the Data Sheet.
85
1.E-04
1.E-03
1.E-02
1.E-01
1.E+00
1.E+01
1.E+02
1.E+03
1.E+04
1.E+05
1.E+00 1.E+01 1.E+02 1.E+03 1.E+04 1.E+05 1.E+06 1.E+07 1.E+08 1.E+09 1.E+10
Imp
ed
an
ce [
Oh
m]
Frequency [Hz]
10% measurement accuracy range (E5061B, Gain-Phase test
port) 100
kΩ
10 kΩ
1 kΩ
100 Ω
10 Ω
1 Ω
100
mΩ
10 mΩ
1 mΩ
10 Hz 100
Hz 1 kHz 10 kHz
100
kHz 1 MHz 10 MHz
100
MHz 1 GHz
E5061B (SPD) Gain-Phase, Series-thru
Definitions - Specification (Spec): Warranted performance. Specifications include guardbands to account for the expected statistical performance distribution,
measurement uncertainties, and changes in performance due to environmental conditions.
- Supplemental performance data (SPD): Represents the value of a parameter that is most likely to occur; the expected mean or average. It is not
guaranteed by the product warranty.
For more details about conditions for defining accuracy, please refer to the Data Sheet.
4-terminal pair test
fixture
86
Series-thru method with gain-phase test port (<=30 MHz)
VT
50
Zdut
VR
+
Internal DC bias
applicable to
capacitive DUTs
P/N 0699-2014 Axial-lead 50 ohm (ESL = approx. 14 nH with minimum lead length)
P/N 0699-2829 SMD 50 ohm
50 ohm R
Calibration
open
short bar
4TP fixture 4-Terminal-Pair type fixture
• For middle to large Z-range
• Need Open/Short/Load cal at fixture
Hc Hp Lc Lp
Examples of load:
Zin=50 ohm Zin=1 Mohm 1 nF capacitor measurement Test freq=100 Hz to 30 MHz Source=7 dBm, IFBW=Auto / 20 Hz-limit
20*log(|Z|) [dB]
Cp [farad]
|Z| [ohm]
100 kohm
100 dB (=100 kohm)
1 nF
T R LF OUT
87
Typical configuration examples for Gain-Phase Series-thru method (Mid-High Z, up to 30 MHz)
- E5061B options
E5061B Network Analyzer
E5061B-3L5 LF-RF NA with DC bias
E5061B-005 Impedance analysis function for LF-RF NA (*1)
---------------------------------------------------------------
E5061B-720 50 Ω resistor set
E5061B-1E5 High stability time base
E5061B-020 Standard hard disk drive
E5061B-810 Add key board
E5061B-820 Add mouse
- 4-terminal pair test fixtures
16047E (leaded component)
16034E (SMD), or 16034G (for SMD)
(*1) E5061B-005 is not applicable to the E5061B RF NA option: 1x5 / 2x5 / 1x7 / 2x7.
E5061B-720 50 Ω resistor set contains the following items for
the impedance calibration at the test fixture:
- SMD 50 Ω (0699-2929), 10 ea
- Leaded 50 Ω (5012-8646), 2 ea
- Tweezers (8710-2018), 1 ea
16047E 16034E
88
Terminal block
BNC(f) receptacle
Copper board (GND)
50 ohm resistor short
wire
DUT
From LF OUT
To R-port (Zin=1 Mohm)
To T-port (Zin=50 ohm)
Series-thru method: Home-made fixtures
Cal devices
89
Z measurement with Network Analyzer (3)
Shunt-thru method Small Zdut
Zdut VT VR
50
50
50
50
50
S21=VT/VR
90
10% measurement accuracy range (E5061B, S-Parameter test
port)
1.E-04
1.E-03
1.E-02
1.E-01
1.E+00
1.E+01
1.E+02
1.E+03
1.E+04
1.E+05
1.E+00 1.E+01 1.E+02 1.E+03 1.E+04 1.E+05 1.E+06 1.E+07 1.E+08 1.E+09 1.E+10
Imp
ed
an
ce [
Oh
m]
Frequency [Hz]
100
kΩ
10 kΩ
1 kΩ
100 Ω
10 Ω
1 Ω
100
mΩ
10 mΩ
1 mΩ
10 Hz 100
Hz 1 kHz 10 kHz
100
kHz 1 MHz 10 MHz
100
MHz 1 GHz
E5061B (SPD) S-Parameter, Shunt-
thru
E5061B (SPD) S-Parameter,
Reflection
Definitions - Specification (Spec): Warranted performance. Specifications include guardbands to account for the expected statistical performance distribution,
measurement uncertainties, and changes in performance due to environmental conditions.
- Supplemental performance data (SPD): Represents the value of a parameter that is most likely to occur; the expected mean or average. It is not
guaranteed by the product warranty.
For more details about conditions for defining accuracy, please refer to the Data Sheet.
91
1.E-04
1.E-03
1.E-02
1.E-01
1.E+00
1.E+01
1.E+02
1.E+03
1.E+04
1.E+05
1.E+00 1.E+01 1.E+02 1.E+03 1.E+04 1.E+05 1.E+06 1.E+07 1.E+08 1.E+09 1.E+10
Imp
ed
an
ce [
Oh
m]
Frequency [Hz]
10% measurement accuracy range (E5061B, Gain-Phase test
port) 100
kΩ
10 kΩ
1 kΩ
100 Ω
10 Ω
1 Ω
100
mΩ
10 mΩ
1 mΩ
10 Hz 100
Hz 1 kHz 10 kHz
100
kHz 1 MHz 10 MHz
100
MHz 1 GHz
E5061B (SPD) Gain-Phase, Shunt-
thru
Definitions - Specification (Spec): Warranted performance. Specifications include guardbands to account for the expected statistical performance distribution,
measurement uncertainties, and changes in performance due to environmental conditions.
- Supplemental performance data (SPD): Represents the value of a parameter that is most likely to occur; the expected mean or average. It is not
guaranteed by the product warranty.
For more details about conditions for defining accuracy, please refer to the Data Sheet.
92
Shunt-thru method
20*log(|Z|) [dB]
|Z| [ohm]
(Linear scale)
Z-phase [deg] S21 [dB]
MLCC (Multi-layer ceramic chip)
measurement in broad freq. range - Test freq=100 Hz to 1 GHz.
• For small Z-range (down to milliohms / sub-
milliohms)
• Calibration method depending on measurement configuration and test freq
T: Zin=50 ohm R: Zin=50 ohm
With S-param. test port (<= 3 GHz):
For most of capacitors, and PCB measurements
With gain-phase test port (<= 30 MHz):
For very-large capacitors (milli-farad order), DC-DC converters
Test board
93
Equivalent Circuit Analysis (1) Equivalent
Circuit Analysis
e.g., Ceramic
Resonator (Type E
circuit)
# Equivalent Circut
# ----C0----
# -| |-
# -L1-C1-R1-
Type, E
R1, 6.94624374266e+000
L1, 6.79827222119e-003
C1, 2.45000000000e-011
C0, 3.47238726000e-010
Simulate =
“ON”
memory trace
94
Equivalent Circuit Analysis (2) Equivalent
Circuit
Analysis
Inductors with high core
loss
Inductors with high winding resistance
or resistors with low resistance value
Resistors with high resistance
value
Capacitors
Resonator
Generally suitable for…
*1.
*2.
*1
*1
*1
*1
*2
Typical freq. characteristics
95
End of E5061B demonstration
96
Methods and Fixtures Summary
Port 1-2 Shunt
Port 1 Refl / Port 2 Refl
Port 1-2 Series
S1
1
S2
1
S21
1MΩ input TR
Power
splitter TR
GP Shunt (T 50Ω, R 50Ω)
GP Series (T 50Ω, R 1MΩ)
S-Parameter (5 Hz - 3 GHz)
Gain-Phase (5 Hz - 30 MHz)
Re
fle
cti
on
S
eri
es
S
hu
nt
7-mm type fixtures
4-Terminal Pair type
fixtures
User fixtures are required
Con
figu
ration
Test port
Applicable
Z-range
Mid
Mid -
High
Low -
Mid
Shunt Series
Mid-Z Low-Z High-Z
1 Ω 1 kΩ 1 mΩ ~ ~ 100
kΩ
97
Summary of Impedance measurement methods
98
Impedance Analysis (E5061B-005) Summary
NA+ZA in one box Supports ZA functions
Provides comprehensive solutions as general R&D
tool:
- Characterize components (ZA)
- Evaluate system performance (NA: S21, T/R)
- Cost effective 5 Hz to 3 GHz impedance analyzer
with moderate performance
Fully supports traditional ZA functions as shown
below:
- Display Z parameters (Z, θz, Ls, Cp, Rs, D, Q, …)
- Impedance Cal. & Fixture Compen
- Equivalent circuit analysis
Migrate legacy combo analyzer (4195A, 4395/96x, 4194A, 4192A)
Covers moderate Z range
Easy to migrate by supporting conventional test
fixtures:
- 7 mm test fixtures (S-Parameter Reflection
method)
- 4TP test fixtures (Gain-Phase Series-thru method)
Covers various ZA applications with three
measurement techniques using both S-Parameter
and Gain-Phase test ports (up to several tens kΩ,
down to around mΩ):
- Reflection method (S-Para.)
- Series-thru method (S-Para./Gain-Phase)
- Shunt-thru method (S-Para./Gain-Phase)
99
Agenda
1. Introduction
2. Impedance Basics & Measurement Methods
3. LCR Meters
4. Impedance Analyzers
5. Accessories/test-fixtures
6. Vector Network Analyzers
• E5061B VNA as Impedance Analyzer
7. Reference Documents + Q&A
100
Key Reference Document Selection Guide
Brief introduction of Agilent
LCR and Impedance
measurement solution
Test accessories / fixtures
compatibility chart
5952-1530E: Agilent LCR Meters, Impedance Analyzers, and Test Fixtures Selection Guide
101
Key Reference Document Accessories Selection Guide
5965-4792E: Accessories Selection Guide For Impedance Measurements
Tips for selecting
appropriate
accessories
Detailed information on
each accessories
102
Key Reference Document Impedance Measurement Handbook
5950-3000; Impedance Measurement Handbook
Deep discussion on each
measurement method
Tips for accurate fixturing
103
Thank You!
104