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June 2012
Agilent Technologies
New impedance measurement
solutions and applications
using a Vector Network Analyzer
Introduction
Vector impedance measurement
X
R
|Z|
Measure real & imaginary parts of impedance vector.
Z = R + jX
R jX
Rs Ls Rs Cs Rp
Cp
Q=1/D=X/R
And mathematically convert to other impedance parameters.
… etc
Page 2
Impedance Analyzers & LCR Meters
Dedicated to Z measurement
High accuracy
Covers low to very high Z range.
Introduction
Agilent’s impedance measurement solutions
NA-based Z meas. solution
NA
ZA
Network Analyzer (NA) plus
Impedance Analyzer (ZA) in one box
Moderate accuracy
Covers very low to high Z range.
E5061B-3L5 LF-RF Network Analyzer
with Opt.005 Impedance Analysis function
Page 3
Agenda
Page 4
• E5061B-3L5 product overview
• Fundamentals on E5061B’s Z-measurement methods
• Calibration methods
• Measurement examples
Page 5
E5061B-3L5 LF-RF Network Analyzer
• 5 Hz to 3 GHz
• S-parameter test port (5 Hz to 3 GHz, 50 Ω)
• Gain-phase test port (5 Hz to 30 MHz, Zin=1 MΩ / 50 Ω switchable)
• Wide dynamic range
• Built-in DC bias source (0 to ±40 Vdc, max 100 mAdc)
• 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
Network Analysis: S-parameter test port (5 Hz to 3 GHz)
Zin
ATT
R1
T1
R2
T2
R
Zin
ATT
T
5 Hz
to
3 GHz
• Full 2-port S-parameter measurement
seamlessly from 5 Hz to 3 GHz
• For evaluating 1- and 2-port devices (Filters, RF amps, cables, antennas, etc)
S11
S21
S22
S12
DUT
Full 2-port S-parameter measurement
S11 S11
S22
S21
1 GHz 10 Hz
-120 dB
Broad freq coverage & wide dynamic range
Page 6
• Receiver Zin switchable to 1 MΩ / 50 Ω
• For evaluating low-freq circuits (DC-DC converter control loops, OP-amp circuits, etc)
Network Analysis: Gain-phase test port (5 Hz to 30 MHz)
Zin
ATT
R1
T1
R2
T2
R
Zin
ATT
T
5 Hz to 30 MHz
Zin= 1 MΩ / 50 Ω
ATT=20 dB / 0 dB
R T LF OUT
DC-DC converter loop-gain measurement
R & T: 1 Mohm
+ A
DUT β
-
Phase margin
Loop gain
0 dB
0 deg
Phase
100 Hz 1 MHz
Source injection transformer
Measure
round transfer function
T/R = -Aβ
Page 7
Page 8
Impedance Analysis: 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
Page 9
MPUs,
MCUs,
FPGAs
RF components S-parameters
Cable loss, impedance Transceiver port Z
A/D
Data bus Tx/Rx
Oscillator circuits
Amp gain & phase, CMRR/PSRR
Sensor circuits
Loop gain & phase Resonator impedance
Tx/Rx
Piezo sensor
impedance
DC-DC conv. phase margin, output-Z EMI filter freq response Passive component impedance Blue: network analysis
Red: impedance analysis
E5061B-3L5/005 (5 Hz to 3 GHz)
“NA + ZA in one box”
DC power supply circuits / Power Distribution Networks
Fully supports your component & circuit evaluations
Wireless interface
Agenda
Page 10
• E5061B-3L5 product overview
• Fundamentals on E5061B’s Z-measurement methods
• Calibration methods
• Measurement examples
Measurement method of Z-analyzers:
Auto balance bridge method
Page 11
V
-
+
2
V 1
Zdut
V2 = -Ir Rr
Zdut = V1
Ir =
-V1 Rr
V2
H L
R r
I r
Virtual GND
Idut
Range
resistors
• 40 Hz to 110 MHz (4294A)
• Very high accuracy
• Very wide Z measurement range due to ranging
(10 % accy range: less than100 mΩ to more than10 MΩ, spec)
• Accurate measurement due to virtual GND (Accurate Vdut & Idut measurement with V1 & V2,
no stray capacitance at low terminal. )
• Test fixtures available: 4TP (4-Terminal-Pair) & 7 mm type
4294A impedance analyzer
Idut=Ir
Vdut
E4980A LCR meter
Measurement method of Z-analyzers:
RF I-V method
Page 12
Source
Voltage meas. ch
Current meas. ch
Test Head
V
Zdut
Receiver
• 1 MHz to 3 GHz
• Detects high-freq voltage & current at close points to DUT
• More accurate & wider Z-measurement range than Reflection method
(10 % accy range: less than1 Ω to 10 kΩ, spec)
• Excellent stability by measuring voltage & current with a single receiver
• Test fixtures available (7 mm type)
E4991A Z-analyzer
E4982A LCR meter
Measurement method of E5061B:
Reflection method
Page 13
• 5 Hz to 3 GHz
• S11 measurement with built-in directional bridge
• For low to mid-Z (10 % accy range: 1 Ω to 2 kΩ, SPD #1)
• Test fixtures available (7 mm type)
16201A 7 mm terminal adapter
7 mm test fixture
Zdut = 50 x (1+S11)/(1-S11)
Zdut VT VR 50 50
50
S11=VT/VR
-30
0
30
60
90
120
150
180
210
1.E
-03
1.E
-02
1.E
-01
1.E
+0
0
1.E
+0
1
1.E
+0
2
1.E
+0
3
1.E
+0
4
1.E
+0
5
1.E
+0
6
S11
ph
as
e (
de
g)
DUT Z (Ω)
100 m
Ω
1 Ω
10 Ω
100 Ω
1 k
Ω
10 k
Ω
100 k
Ω
1 M
Ω
1 m
Ω
10m
Ω
50 Ω
High sensitive area ( Z range where magnitude or phase
of measured vector voltage ratio
dynamically varies.)
# Case of
reactive DUT
#1. SPD: Supplemental Perf. Data
Measurement method of E5061B:
Series-thru method
Page 14
VT 50
50 T/R=VT/VR
Zdut
• 5 Hz to 30 MHz (Gain-phase test port)
• 5 Hz to several-100 MHz (S-parameter Port 1-2)
• For mid to high-Z (10 % accy range: 5 Ω to 20 kΩ, SPD)
• Test fixtures available (for gain-phase test port)
• Not applicable to grounded DUTs
Zdut
50 S21=VT/VR
VR 50 VT
50
DUT
Zdut = 50 x S21/(2 x (1-S21))
VR 1 MΩ
Gain-phase series-thru Port 1-2 series-thru
Port-1 Port-2
-100.0
-80.0
-60.0
-40.0
-20.0
0.0
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
S21
or
T/R
(d
B)
DUTのZ値 (Ω)
1 m
Ω
10m
Ω
100 m
Ω
1 Ω
10 Ω
100 Ω
1 k
Ω
10 k
Ω
100 k
Ω
1 M
Ω
50 Ω High sensitive
area
# Case of
reactive DUT
DUT Z (Ω)
S2
1 o
r T
/R (
dB
)
DUT DUT
Power splitter
Zdut VT VR
50
50
50
50
50
S21=VT/VR
• 5 Hz to 30 MHz (Gain-phase port), 5 Hz to 3 GHz (S-parameter Port 1-2)
• For very low Z (10 % accy range: less than 1 mΩ to 5 Ω)
Better low-Z measurement sensitivity than Z-analyzers
• Home-made fixtures, or RF probes
Gain-phase shunt-thru Port 1-2 shunt-thru
Page 15
Zdut = 50 x S21/(2 x (1-S21))
-100.0
-80.0
-60.0
-40.0
-20.0
0.0
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
S21
or
T/R
(d
B)
DUTのZ値 (Ω)
1 m
Ω
10m
Ω
100 m
Ω
1 Ω
10 Ω
100 Ω
1 k
Ω
10 k
Ω
100 k
Ω
1 M
Ω
50 Ω High sensitive area
Measurement method of E5061B:
Shunt-thru method
DUT Z (Ω)
S2
1 o
r T
/R (
dB
)
# Case of
reactive DUT
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+02 1.0E+04 1.0E+06 1.0E+08 1.0E+10
DU
T Im
pe
da
nce
(oh
m)
Freq.(Hz)
Elfin Impedance measurement accuracy (S.P.D)
Port1 Reflection Port1-2 Shunt Port1-2 Series
Z-measurement accuracy at S-parameter test port (10 % accuracy range: Supplemental Performance Data)
1 MΩ
100 kΩ
10 kΩ
1 kΩ
100 Ω
10 Ω
1 Ω
100 mΩ
10 mΩ
1 mΩ
100 uΩ
Port 1-2
series-thru method
Port 1
reflection method
Port 1-2
shunt-thru method
1 Hz 10 Hz 100 Hz 1 kHz 10 kHz 100 kHz 1 MHz 10 MHz 100 MHz 1 GHz
(Note-2)
Note-1) Need to use magnetic cores to measure very low Z at low frequencies.
Note-2) Case of 20 pH residual inductance.
(Note-1)
Page 16
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+02 1.0E+04 1.0E+06 1.0E+08 1.0E+10
DU
T Im
pe
da
nce
(oh
m)
Freq.(Hz)
Elfin Impedance measurement accuracy (S.P.D)
GP Series (T 50Ω_20dB, R 1MΩ_20dB) GP Shunt (T 50Ω_0dB, R 50Ω_20dB)
1 1Hz 10 Hz 100 Hz 1 kHz 10 kHz 100 kHz 1 MHz 10 MHz 100 MHz 1 GHz 10 GHz
1 MΩ
100 kΩ
10 kΩ
1 kΩ
100 Ω
10 Ω
1 Ω
100 mΩ
10 mΩ
1 mΩ
100 uΩ
Gain-phase
series-thru method
Gain-phase
shunt-thru method
Page 17
Note-2) Case of 20 pH residual inductance.
(Note-2)
Z-measurement accuracy at Gain-phase test port (10 % accuracy range: Supplemental Performance Data)
How to select measurement method
Page 18
Freq range
of interest
Z range of
interest
Recommended method Typical DUT examples
High freq
(over 100 MHz)
Mid Z (1Ω to several kΩ)
Reflection RF inductors/capacitors,
other RF passive components
Low Z (<100 mΩ) Port 1-2 shunt Small bypass caps, PDNs
Low freq (up to 100 MHz)
High Z (>10 kΩ) Gain-phase series (up to 30 MHz)
Port 1-2 series (up to 300 MHz)
Small capacitors, resonators,
inductors, transformers
Mid Z (1Ω to 10kΩ) Reflection Inductors, transformers, resonators
Low Z (<100 mΩ) Gain-phase shunt (up to 30 MHz)
Port 1-2 shunt (over 100 kHz)
DC-DC converters,
mid or large bypass caps, PDNs
Recommended Z measurement method with E5061B
• Need very high accuracy ( < 1 % )
• Measure high Q (>100), low D (<0.01) or very small Rs of
inductors & capacitors
• Measure very high impedance ( |Zdut| > 100 kΩ )
• Measure dielectric / magnetic materials
X=-1/(2*pi*f*C)
Rs
DUT’s Z vector
D=1/Q=Rs/X
4294A/E4991A Z-analyzers are recommended in the following cases…
Meas. error
10% accuracy range comparison
with Z-analyzers & legacy NA/ZA combo analyzer
Total range of 3 methods at S-param. 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.
19
Migration paths for legacy NA/ZA combo analyzers
Page 20
4195A+41951A (100 k to 500 MHz)
4194A (ZA: 100 Hz to 40 MHz)
4192A (5 Hz to 13 MHz)
4395A/96x+43961A (100k to 500 M/1.8 GHz)
Typical DUTs: Ceramic resonators, piezo sensors, crystal resonators, small capacitors, large inductors, etc
Typical DUTs: Inductors, transformers, large capacitors, RFID, antenna coils, crystal resonators, RF passive components, etc
Measure milliohm Z of
large capacitors & DC-DC conv.
Main migration path
Main migration path
E5061B-3L5/005
Reflection method 5 Hz to 3 GHz, for low to mid Z
Need higher freq.
Measure low Z.
Measure
high Z.
E5061B-3L5/005
Shunt-thru methods
E5061B-3L5/005
Gain-phase series-thru method 5 Hz to 30 MHz, for mid to high Z
Measure high-Q / low-D,
very high Z 4294A / E4991A Z-analyzers
Agenda
Page 21
• E5061B-3L5 product overview
• Fundamentals on E5061B’s Z-measurement methods
• Calibration methods
• Measurement examples
Typical calibration for Reflection method
Page 22
7 mm fixture
Open/Short compensation Residual Z & stray C
Phase shift at
50 Ω coax section Electrical length compensation
(Port extension)
7 mm connector Open/Short/Load cal
(+ optionally
Low-loss capacitor cal)
16201A
Terminal adapter
To
Port-1
Semi-rigid cable Note) Low-loss capacitor cal:
Improves phase uncertainty of load standard at high
frequencies by measuring air capacitor whose phase angle
can be regarded as ideal 90 degree.
Typical calibration for Series-thru method
Page 23
Zdut 50 Ω
O/S/L cal at 4TP fixture
open
Short
Gain-phase series (5 Hz to 30 MHz): O/S/L cal
Hc Hp Lc Lp
1 MΩ input
T R LF OUT
50 Ω input
DUT Port extension
SOLT cal
Plus, possible to eliminate stray-C
with open compensation.
Port 1-2 series (5 Hz to several-100 MHz): O/S/L cal, or SOLT cal + PE (+ O/S compen)
Source
E5061B-720
50 Ω resistor set
Typical calibration for Shunt-thru method
Page 24
Open Short 50 Ω
Gain-phase shunt (5 Hz to 30 MHz):
Thru
DUT
a) Thru cal only
b) Open/Short/Load cal
You can obtain enough accuracy if you just
measure |Z|, or the major part of Z vector (L, C).
If you want to further improve measurement
accuracy, especially at large Z range over
1 Ω, perform Open/Short/Load cal instead
of Thru cal.
Port 1-2 shut (up to several-100 MHz or GHz ranges):
SOLT cal SOLT cal + PE, or SOLT cal at fixture/probe
Port extension
SOLT cal DUT
ISS stds
Agenda
Page 25
• E5061B-3L5 product overview
• Fundamentals on E5061B’s Z-measurement methods
• Calibration methods
• Measurement examples
100 nH inductor measurement
Page 26
4294A
-1.5E-07
-5.0E-08
5.0E-08
1.5E-07
2.5E-07
3.5E-07
1.E+04 1.E+05 1.E+06 1.E+07 1.E+08 1.E+09
Reflection
E4991A
0
10
20
30
40
50
60
1.E+04 1.E+05 1.E+06 1.E+07 1.E+08 1.E+09
Reflection
4294A
E4991A
E5061B
Reflection
E5061B
Reflection
10 kHz 100 k 1 M 10 M 100 M 1 GHz
E5061B setup: Reflection method Freq = 10 kHz to 3 GHz Source = -10 dBm, IFBW = 30 Hz OSL & Low-loss-C cal + Port ext. + OS comp
4294A (AVG=4)
4294A (AVG=4)
E4991A (AVG=8)
E4991A (AVG=8)
10 kHz 100 k 1 M 10 M 100 M 1 GHz
|Z| Phase
Ls Q
1 kΩ
1 Ω
100 nH
100 Ω
Q
Ls (H)
Good data agreement with 4294A /
E4991A in both Ls and Q.
Measurement in the
very broad freq range
-0.02
0.00
0.02
0.04
0.06
0.08
0.10
1.E+02 1.E+03 1.E+04 1.E+05 1.E+06 1.E+07
GPseries
4294A
10 nF capacitor measurement
Page 27
7.0E-09
7.5E-09
8.0E-09
8.5E-09
9.0E-09
9.5E-09
1.0E-08
1.E+02 1.E+04 1.E+06
GPseries
4294A
E5061B setup: Gain-phase series-thru method Freq = 100 Hz to 10 MHz Source = 0 dBm, IFBW = Auto / 20 Hz-limit Calibration : Open/Short/Load cal
100 Hz 1 k 10 k 100 k 1 M 10 MHz
100 Hz 1 k 10 k 100 k 1 M 10 MHz
17.7 kΩ
1 kHz
Cp (F)
D
|Z| Phase
Cp D
Good data agreement with
4294A, except noisy area
at low freq range
4294A (AVG=4)
4294A (AVG=4)
E5061B
GP-series
E5061B
GP-series
200 uF capacitor measurement
Page 28
0.000
0.005
0.010
0.015
0.020
0.025
0.030
0.035
0.040
1.E+03 1.E+04 1.E+05 1.E+06 1.E+07 1.E+08
GPshunt (Thru)
GPshunt (OSL)
Port 1-2 shunt
4294A
-5.0E-05
0.0E+00
5.0E-05
1.0E-04
1.5E-04
2.0E-04
2.5E-04
1.E+03 1.E+04 1.E+05 1.E+06 1.E+07 1.E+08
GPshunt (Thru)
GPshunt (OSL)
Port 1-2 shunt
4294A
|Z| Phase
Cs
Rs
1 k 10 k 100 k 1 M 10 MHz
1 k 10 k 100 k 1 M 10 MHz
Cs (F)
Rs (Ω)
100 mΩ
10 mΩ
100 mΩ
10 mΩ
200 uF
E5061B setup: Freq = 1 kHz to 10 MHz Source = -10 dBm, IFBW = Auto / 20 Hz-limit Gain-phase shunt method * Thru cal, or O/S/L cal * T-port ATT: 0 dB Port 1-2 shunt method * SOLT cal + Port ext. * Large magnetic core attached to test cable
Good data agreement with 4294A with better SNR
4294A (AVG=8)
4294A (AVG=8)
Thru cal: Error at high freq range
Crystal resonator measurement
|Z|
Phase
DUT: 14 MHz SMD crystal resonator (with short leads soldered to electrodes for fixturing) E5061B setup: Reflection method (16201A + 16092A 7 mm fixture) NOP = 201, IFBW = 30 Hz, Source = -19 dBm
Wide span covering both Fr & Fa (Center=14.405 MHz, Span = 30 kHz) • C0, C1 and L1 can be extracted. • Measured CI is not correct. - Sweep time is not slow enough - Freq resolution is not enough
Narrow span focusing at Fr area (Center=14.39623 MHz, Span=3 kHz) • C0 cannot be extracted (because Fa is not measured).
• CI is accurately measured. - Sweep time for scanning around Fr is sufficiently slow. - Freq resolution around Fr is fine.
Fr (Phase = 0 deg)
CI
Fa
CI = 21 Ω CI = 14 Ω
C0=2.8 pF, C1=7.2 pF, L1=16.7 mH
Fr (Phase = 0 deg)
CI
C0=zero, C1=7.2 pF, L1=16.7 mH
Page 29
DC voltage biased measurement
Page 30
-30%
+10%
0%
Cs
0 Vdc -10 Vdc +10 Vdc
Y5V 100 nF ceramic capacitor measurement
Gain-phase series-thru method
DC bias applied with internal DC source
|Z|
Phase
Cs
Rs
Ch1:
Freq sweep
(100 Hz to 30 MHz)
Ch2:
DC bias sweep
(-10 to +10 Vdc,
CW=10 kHz)
DC current biased measurement
Page 31
16200B DC bias adapter
DC current from external DC source 7 mm Test fixture
Bias=0 A
0.5 A 1 A
2 A |Z|
100 Ω
160 Ω
Ferrite bead measurement Reflection method
Freq = 1 MHz to 1 GHz
DC bias = 0 to 2 Adc (from external DC source)
16201A terminal adapter
16200B DC current bias adapter
1 MHz to 1 GHz
Max 5 Adc
Large-AC Z measurement
Page 32
50
VR 1 MΩ
1/N2 1/N1
× N
Zin Zout
Voltage divider circuits:
Attenuate V1 and V2 down to
receiver’s max input level
(1.78 Vpeak @ATT=20 dB)
Rc High-power resistor
(for detecting
AC current flowing
thru DUT)
Zdut
V2 = R x Idut
Idut
50 Ω
open
Short
Perform O/S/L cal
by reducing power amp
output level down to 50
ohm resistor’s tolerable
level.
Power amp
Expanding AC source level using external
power amp
• Series-thru method with 1 MΩ receiver input-Z
• Max signal level up to 50 Vrms / 1 Arms
(depends on power amp)
• For high-power measurement of capacitors,
power inductors, piezo ceramics, … etc
LF OUT R
VT 1 MΩ
T
E5061B-3L5/005
NF HSA4101
Bipolar amp.
DC to 10 MHz Zin=50 Ω
Zout=1.5 Ω+0.5 uH
(1.8 Ω @100 kHz)
Output Input
R (1 MΩ//30 pF,
ATT=20 dB)
LF
OUT
DUT (36 uH )
R1 R2
C1
1/50 divider R1=464 kΩ, 0.25W
R2=10 kΩ, 0.25W
(C1: stray-C of R1)
T (1 MΩ//30 pF,
ATT=20 dB)
R1 R2
C1
Rc=1.1 Ω, 4W (2.2 Ω / / 2.2 Ω)
E5061B-
3L5/005
Page 33
Power sweep at CW = 100 kHz
Source = -20 to +8 dBm (0.225 to 0.58 Vrms @50Ω)
Amp gain = 50 (Output level = 1.12 to 29 Vrms)
1 Arms flows thru DUT when source
power is +7 dBm.
(|Zdut| + Zout + Rc = approx. 25 Ω,
power amp output = 25 Vrms)
1/11 divider R1=147 k Ω, 0.25W
R2=14.7 kΩ, 0.25W
C1=2.7 pF Ls Rs
|Z|
22.9 Ω
AC voltage
at R-port
7 dBm
35.8 uH
36.4 uH
Power inductor measurement example
Circuit impedance measurement Reflection method
Page 34
Simple hand-probing with
SMA RF cable + probe head
• Applicable test freq: up to 100 MHz
• For in-circuit Z measurements of
components/circuits on PCBs, such as
RFID pattern antennas
Probe head of 42941A impedance probe (PN 42941-60002)
SMA(f)-SMA(f)
SMA(m) cable covered with non-metal material
OSL cal
Open/Short compensation
To Port-1
Hold non-metal part of cable
|Z| Phase
Ls
Q
1 kΩ
3 kΩ
1 uH
Measurement of LC resonant circuit on PCB
(1 MHz to 60 MHz)
Circuit impedance measurement DC-DC converter output Z measurement
E5061B Setup:
Gain-phase shunt-thru method
Freq = 100 Hz to 10 MHz, IFBW=10 Hz
T: Zin=50 Ω, ATT=0 dB
R: Zin=50 Ω, ATT=20 dB
Source=10 dBm (-10 dBm when performing thru cal)
Page 35
Load
Power supply
R&T : 50 Ω inputs
DUT
Feedback Loop
Insert 1 mF capacitors for DC blocking when DUT’s
output voltage is more than 5 Vdc (up to 10 Vdc or so).
100 mΩ
10 mΩ
1 mΩ
|Z| |Z|
Converter OFF Converter ON
Solder SMA receptacles to
DUT’s output port
10 MHz 10 Hz
Circuit impedance measurement High freq PDN Z measurement for MPU board
Page 36
1 mΩ
Bypass caps
SMA receptacles are soldered to thru holes where a
bypass cap was removed. (Avoid inter-probe coupling
error by probing from top and bottom of PCB.)
A large magnetic core is attached to test cable
to eliminate the GND loop error.
GND plane
Vdd plane
E5061B setup:
Port 1-2 shunt-thru method
Freq = 100 Hz ~ 1 GHz
Source=10 dBm, IFBW=Auto / 100 Hz limit
SOLT cal at test cable ends + Port extension
10 mΩ
100 mΩ
To Port-1
To Port-2
Via inductances on the 2-port section
do not affect on inter-plane Z
measurement.
100 MHz
|Z|
100 Hz
Summary
Page 37
• To get the most of the E5061B’s Z-measurement abilities,
Select appropriate measurement methods to your DUTs.
Use appropriate fixtures and test cables.
Pay attention to analyzer’s setup, calibration, and fixturing / probing.
• Combination with external instruments or simple circuitries
further expands the E5061B’s Z measurement applications.