Quadtech 7600 User Manual
7600 Precision LCR Meter
Model B
Instruction Manual
Form 150261/A4
©QuadTech, Inc., 1997
5 Clock Tower Place, 210 East
Maynard, Massachusetts, U.S.A. 01754-2530
October, 2002
Tel. 978-461-2100
800-253-1230
Fax. 978-461-4295
http://www.quadtech.com
The material in this manual is for informational purposes only and is subject to change,
without notice. QuadTech assumes no responsibility for any error or for consequential
damages that may result from the misinterpretation of any procedures in this publication.
!
Product will be marked with this symbol (ISO#3684) when it is necessary for the user to
refer to the instruction manual in order to prevent injury or equipment damage.
Product marked with this symbol (IEC417) indicates presence of direct current.
ii
Contents
Warranty ............................................................................................................vii
Specifications ............................................................................................................ix
Introduction - Section 1
1.1 Unpacking and Inspection .............................................................................1-1
1.2 Product Overview ..........................................................................................1-1
1.3 Controls and Indicators..................................................................................1-2
1.4 Accessories Included .....................................................................................1-5
1.5 Accessories/Options Available......................................................................1-5
1.6 Installation .....................................................................................................1-6
1.6.1 Instrument Positioning.......................................................................1-6
1.6.2 Power Requirements..........................................................................1-6
1.6.3 Safety Inspection................................................................................1-7
Operation - Section 2
2.1 General...........................................................................................................2-1
2.2 Startup ............................................................................................................2-1
2.3 Connection to Device Under Test..................................................................2-1
2.4 Zeroing...........................................................................................................2-2
2.5 Measurement Procedure ................................................................................2-3
2.5.1 General...............................................................................................2-3
2.5.2 Default Measurement Conditions......................................................2-3
2.6 Menu Functions .............................................................................................2-5
2.6.1 General...............................................................................................2-5
2.6.2 Setup Menu........................................................................................2-5
2.6.2.1 Primary Parameter ................................................................2-6
2.6.2.2 Secondary Parameter ............................................................2-9
2.6.2.3 Frequency..............................................................................2-10
2.6.2.4 AC Test Signal......................................................................2-10
2.6.2.5 DC Bias Voltage...................................................................2-11
2.6.2.6 Range Hold ...........................................................................2-14
2.6.2.7 Range Locked .......................................................................2-15
2.6.2.8 Measurement Accuracy ........................................................2-20
2.6.2.9 Measurement Delay..............................................................2-20
2.6.2.10 # to Average........................................................................2-21
2.6.2.11 Contact Check.....................................................................2-21
iii
Contents (continued)
2.6.3 I/O Menu............................................................................................2-22
2.6.3.1 Display Type.........................................................................2-23
2.6.3.2 Nominal Value......................................................................2-26
2.6.3.3 Result Format........................................................................2-26
2.6.3.4 Trigger ..................................................................................2-27
2.6.3.5 Handler Interface ..................................................................2-27
2.6.3.6 RS-232 Interface...................................................................2-27
2.6.3.7 IEEE-488.2 Interface ............................................................2-28
2.6.3.8 Print Results..........................................................................2-28
2.6.3.9 Results to Floppy ..................................................................2-29
2.6.4 Analysis Menu...................................................................................2-35
2.6.4.1 Binning..................................................................................2-36
2.6.4.2 Test Sequencing....................................................................2-41
2.6.4.3 Parameter Sweep...................................................................2-44
2.6.4.4 Median ..................................................................................2-46
2.6.4.5 Distortion Detection..............................................................2-46
2.6.4.6 Load Correction....................................................................2-46
2.6.5 Utilities Menu....................................................................................2-48
2.6.5.1 Save Setup.............................................................................2-49
2.6.5.2 Recall Setup..........................................................................2-50
2.6.5.3 Setup Accuracy.....................................................................2-51
2.6.5.4 Open / Short..........................................................................2-54
2.6.5.5 Lock Out ...............................................................................2-55
2.6.5.6 Calibration ............................................................................2-56
2.6.5.7 Set Time/Date .......................................................................2-56
2.6.5.8 Usage/Cal Date .....................................................................2-57
2.6.5.9 Set Contrast...........................................................................2-57
2.6.5.10 Self Test..............................................................................2-58
2.6.5.11 LCD Backlite......................................................................2-58
2.7 Input/Output Interface....................................................................................2-59
2.7.1 I/O Interface.......................................................................................2-59
2.7.2 Parallel Interface................................................................................2-63
2.7.3 IEEE-488.2 Interface .........................................................................2-64
2.7.3.1 Formats .................................................................................2-74
2.7.3.2 Sample Program for National Instruments GPIB card .........2-76
2.7.4 RS232 Interface .................................................................................2-77
2.7.5 Results to Printer................................................................................2-78
iv
Contents (continued)
2.8 Operation with Accessories...........................................................................2-79
2.8.1 General...............................................................................................2-79
2.8.2 Rack Mount Kit (7000-00) ................................................................2-79
2.8.3 BNC Cable Set, 1 Meter (7000-01), 2 Meter (7000-02)....................2-79
2.8.4 Kelvin Clip Leads (7000-03).............................................................2-80
2.8.5 Alligator Clip Leads (7000-04)..........................................................2-82
2.8.6 Chip Component Tweezers (7000-05)...............................................2-83
2.8.7 Low V, Axial/Radial Lead Component Test Fixture (7000-06)........2-84
2.8.8 Low V, Chip component Test Fixture (7000-07) ..............................2-85
2.8.9 High Voltage Test Fixture (7000-08) ................................................2-87
2.8.10 Calibration Kit (7000-09) ..................................................................2-88
2.8.11 Connections to 874 Type Adapters....................................................2-89
2.9 Error Messages ..............................................................................................2-90
Theory Section 3
3.1 General...........................................................................................................3-1
3.2 Instrument Description ..................................................................................3-1
3.2.1 Basic I2000 Instrument Architecture.................................................3-1
3.2.2 7600 Instrument Module....................................................................3-2
3.2.3 I2000 Instrument Options..................................................................3-3
Maintenance/Calibration - Section 4
4.1 General...........................................................................................................4-1
4.2 Instrument Return ..........................................................................................4-1
4.3 Routine Maintenance.....................................................................................4-1
4.3.1 Battery Replacement..........................................................................4-1
4.3.2 Bias Voltage Fuse Replacement ........................................................4-2
4.3.3 Resetting of Time and Date ...............................................................4-2
4.3.4 Loss of Display Contrast....................................................................4-3
4.3.5 Preventive Maintenance/Cleaning.....................................................4-4
4.4 Calibration .....................................................................................................4-4
4.4.1 General...............................................................................................4-4
4.4.2 Calibration Procedure........................................................................4-4
v
vi
Warranty
QuadTech warrants that Products are free from defects in material and workmanship and,
when properly used, will perform in accordance with QuadTech's applicable published
specifications. If within one (1) year after original shipment it is found not to meet this
standard, it will be repaired, or at the option of QuadTech, replaced at no charge when
returned to a QuadTech service facility.
Changes in the Product not approved by QuadTech shall void this warranty.
QuadTech shall not be liable for any indirect, special or consequential damages,
even if notice has been given of the possibility of such damages.
This warranty is in lieu of all other warranties, expressed or implied, including, but
not limited to any implied warranty or merchantability or fitness for a particular
purpose.
SERVICE POLICY
QuadTech policy is to maintain product repair capability for a period of at least five (5)
years after original shipment and to make this capability available at the then prevailing
schedule of charges.
vii
viii
Specifications
Measurement Capacitance (Cs/Cp), Inductance (Ls/Lp), Resistance (Rs/Rp),
Parameters: Dissipation (DF) and Quality (Q) Factors, Impedance (|Z|),
Admittance |Y|, Phase Angle (θ), Equivalent Series Resistance
(|ESR|), Conductance (Gp), Reactance (Xs), Susceptance (Bp)
Any two parameters measured and displayed simultaneously
Measurement |Z|, R, X: 000.0001 mohm to 99.99999 Mohm
Ranges: |Y|, G, B: 00000.01 µS to 9.999999 MS
C: 00000.01 fF to 9.999999 F
L: 0000.001 nH to 99.99999 H
D: .0000001 to 99.99999
Q: .0000000 to 999999.9
Phase Angle: -180.0000 to +179.9999 degrees
Delta %: -99.9999 % to +99.9999 %
Measurement Fast Medium Slow
Accuracy: LCR: +/- 0.5%* +/- 0.25%* +/- 0.05%*
DF: +/- 0.005 +/- 0.0025 +/- 0.0005
* At optimum test signal levels, optimum DUT value and without calibration
uncertainty error. Instrument accuracy can be reduced from nominal specifications
when using some 7000 accessory fixtures and cables. Best accuracy requires geometric
consistency between that utilized during open/short zeroing and that utilized on fixtures
and cables during the actual measurement process. This consistency may be especially
difficult to achieve when using unshielded Kelvin clip and tweezer type connections.
0.25 x (normal accuracy) with Load Correction implemented and
compared to user supplied standard.
In a range of 3Ω ≤ Z ≤ 80kΩ, 100mV ≤ programmed V ≤ 1V or
100mV ≤ (programmed I) x (Z) ≤ 1V
Test Frequency: 10 Hz to 2 MHz
Resolution: 0.1 Hz from 10 Hz to 10 kHz
5 digits > 10 kHz, 4 digits > 100 kHz
Accuracy: +/- (0.25% + 0.02 Hz)
Measurement Speed: Fast Accuracy: 40 msec*/measurement
Medium Accuracy: 125 msec*/measurement
Slow Accuracy: 1 sec*/measurement
* may be longer, depending on test conditions & frequency
Ranging: Automatic or Range Hold
Note: s = series, p = parallel, ESR equivalent to Rs
ix
Specifications (continued)
Source Impedance: 25Ω, 400Ω, 6.4 kΩ or 100 kΩ, measurement range dependent
Trigger: Internal (automatic) and External (via handler, RS-232 or IEEE-
488.2 interfaces)
AC Test Signal 20 mV to 5.0 V (open circuit) in 5 mV steps, ≤500kHz
Voltage: 20 mV to 1.0 V (open circuit) in 5 mV steps, >500kHz to≤1MHz
20 mV to 0.5 V (open circuit) in 5 mV steps, >1MHz
Accuracy: +/- (5% + 1 mV) < 100kHz
+/- (10% + 1 mV) 100kHz to 500kHz
+/- (20% + 1 mV) 500kHz to 1MHz
+/- (35% + 1 mV) > 1MHz
AC Test Signal 250 µA to 100 mA (short circuit) in 50 µA steps
Current: Max Compliance: 3V < 500kHz, 1V from 500kHz - 1MHz
0.5V > 1MHz
Accuracy: +/- (5% +50 µA) < 100kHz
+/- (10% +50 µA) 100kHz to 500kHz
+/- (20% +50 µA) 500kHz to 1MHz
+/- (35% +50 µA) > 1MHz
Bias Voltage: Internal: 2.0 V External: 0 to +/-200 V
Display: LCD Graphics with adjustable contrast and back light
- Results of Dual Measurement Parameters in engineering
(7 digits) or scientific (5 digits) notation
- Deviation from Nominal of Primary Parameter
- % Deviation from Nominal of Primary Parameter
- Instrument Setting and Test Conditions
- Bin Limits and Pass/Fail Results
- Plot of Primary Measurement Parameter vs. Test Conditions
- Table of Measurement Parameters vs. Test Conditions
- Sequenced Test Results Summary
Limit Detection: 15 bins total (10 pass, 4 fail, 1 no contact)
Interfaces: IEEE-488.2, RS-232, Handler, Printer Port and 3.5" Floppy Dr.
Front Panel Four terminal (BNC) with Guard
Test Terminals:
Environmental: MIL-T-28800E, Type 3, Class 5, Style E & F.
Operating: 0 to + 50o C. Storage: - 40 to + 71o C.
Humidity: < 75% for < 40o C operating
Altitude <2000m, Installation Category 1, Pollution Degree 1
x
Specifications (continued)
Mechanical: Bench mount with tilt bail
Dimensions: (w x h x d): 16 x 6 x 14in
(410 x 150 x 360mm)
Weight: 17 lbs (8kg) net, 23 lbs (10.5kg) shipping
Power Requirements: 90 to 250Vac 47 - 63 Hz 40W maximum
Other Features: Charged Capacitor Protection: 8/C for Vmax ≤ 250 V
2/C for Vmax ≤ 1000V
C = Capacitance in farads of the device under test
Measurement Delay programmable from 0-1000 ms in 1 ms steps
Measurement Averaging programmable from 1-1000
Median value Mode
Open and Short Circuit Zeroing at Multiple Frequencies
Power Fail Protection (setting, results, & calibration data stored)
Storage and Recall of 25 Setups, 125/disk w/Floppy Option
Self-Test Routines at Power-up
Stored Results up to 40,000 measurements/disk w/Floppy Option
Self Accuracy Calibration and Display
Contact Check
Supplied: Instruction Manual Power Cable Calibration Certificate
Ordering Description Catalog No.
Information:
7600 Precision LCR Meter, Model B 7600
7600-CE Precision LCR Meter, Model B 7600-CE
7600A Precision LCR Meter, Model B,+/-500V ext bias 7600A
7600A-CE Precision LCR Meter, Model B 7600A-CE
+/-500V ext bias
Options & Accessories:
Rack Mount Kit 7000-00
BNC Cable Set, 1 meter 7000-01
BNC Cable Set, 2 meters 7000-02
Kelvin Clip Leads 7000-03
Alligator Clip Leads 7000-04
Chip Component Tweezers 7000-05
Low Voltage Axial/Radial Lead Component Test Fixture 7000-06
Low Voltage Chip Component Test Fixture 7000-07
High Voltage Test Fixture 7000-08
Calibration Kit 700009
xi
xii
Section 1 Introduction
1.1 Unpacking and Inspection
Inspect the shipping carton before opening, if damaged contact the carriers agent
immediately. Inspect the instrument for any damage. If the instrument appears damaged
or fails to meet specifications notify QuadTech (refer to instruction manual front cover)
or its local representative. Retain the shipping carton and packing material for future use
such as returning for re calibration or service.
1.2 Product Overview
The 7600 Precision LCR Meter is an automatic, user programmable instrument for
measuring a wide variety of impedance parameters. The 7600 covers a frequency range
from 10 Hz to 2 MHz with a basic measurement accuracy of 0.05%. The instruments
high resolution graphics display and keypad makes for easy menu programming. Test
conditions are stored and recalled from internal memory, eliminating wasted
measurement setup time. Extensive pass/fail binning capability and measurements
speeds up to 25/sec makes the unit well suited for production applications.
The instruments unique measurement sequencing allows up to six parameters to be
measured on a single pass. Additionally, a parameter can be plotted against a test
condition variable, an invaluable technique for component design and product evaluation.
The 7600 comes with IEEE-488.2, RS-232, I/O port (handler), and parallel interfaces, all
standard, for remote control operation and communication with other instrumentation. A
3 1/2" floppy drive is also included for program/data storage of test conditions and
measurement results.
Precision
7600
LCR Meter
!
CAUTION
HIGH VOLTAGE
DISPLAY SELECT ENTRY TESTQuadTech
17.52520 pF
C
.0000100
DF
Freq
1.0000kHz
Range
0 ms
Delay
AC Signal
AverageAuto
Bias
1.0000V
1
Off
12
4
5
8
7
-
0
FAIL PASS
MENU
3
CNCL
ENTER
STOP
START
6
9
.
Figure 1-1
7600 Precision LCR Meter
Introduction 1-1
1.3 Controls and Indicators
Figure 1-2 shows the controls and indicators on the front panel of the 7600. Table 1-1
identifies them with descriptions and functions.
234567
910
Precision
7600
LCR Meter
!
CAUTION
HIGH VOLTAGE
DISPLAY SELECT ENTRY TESTQuadTech
C
17.52520 pF
DF
.0000100
Freq
1.0000kHz
Range
Delay
AC Signal
AverageAuto
Bias0 ms
1.0 V
1
Off
12
4
5
8
7
-
0
8
FAIL PASS
MENU
3
CNCL
ENTER
11 12 131
STOP
START
6
9
.
Figure 1-2
Front Panel Controls & Indicators
Table 1-1
Front Panel Controls and Indicators
Figure 1-2
Ref. No. Item Function
1 Input Panel BNC connectors, for connection to device
under test (DUT). 7/8 inch spacing.
IL Current, low connection to DUT
PL Potential, low connection to DUT
PH Potential, high connection to DUT
IH Current, high connection to DUT
2 Voltage indicator Indicates when dc bias voltage is called for
or applied to rear panel connectors, from
external source
3 Graphics display Displays test conditions, measured results,
instrument status and user interface menus.
Introduction 1-2
Table 1-1 (continued)
Front Panel Controls and Indicators
Figure 1-2
Ref. No. Item Function
4 Select keys (4) Soft key functions as indicated on the
adjacent LCD display.
- from top to bottom, functions such as up,
down, right or left arrow during menu
selection.
- other functions such as measurement
units, exponent, Y or N (yes or no) and del
(delete).
5 Keypad (12) For making numerical entries as labeled,
0 through 9, minus sign and decimal.
6 CNCL key Exits an active field in vertical or
horizontal selections, clears entry on #
fields when pressed once and exits # fields
when pressed twice.
7 MENU key Enters menu display mode or exits sub
menu back to main menu.
8 ENTER key Switches user to entry mode or accepts
menu entry as entered.
9 Pass/Fail indicator Indicates measurement results based on
entered test limits.
10 STOP key Stops the measurement process.
11 START key Starts the measurement process.
12 Power switch Turns main power to instrument on or off.
13 Floppy drive For storing measurement setup conditions
and measurement results. A high density
(1.44M) or low density (720K) DOS
compatible floppy drive. Floppies should
be double sided, formatted for DOS
compatibility.
Introduction 1-3
1 2
4
6 7
BIAS VO LT AG E
200V M AX
+
BAT TERY
-
90 - 250 V
47 - 63 Hz
40 WATTS M AX
IEEE- 488 INT ERF ACE
PARALL EL POR T RS-232 I NT ERF ACE
I/O PO R T
3
5
Figure 1-3
Rear Panel View
Table 1-2
Rear Panel Connectors and Controls
Figure 1-3
Ref. No. Item Function
1 ! AC Inlet Module AC power input, filtering, fusing and
switching. Use with Belden SPH386 socket or equivalent. Contains
T2.5A,
250V, 5x20mm time delay fuse for 115 or
220V operation. Replace only with the
same type and rating. Also refer to
paragraph 1.6.2.
2 IEEE-488.2 Input/output connections according to IEEE
STD-488.2. 24 pin socket for standard
IEEE-488 cable. Refer to paragraph 2.7.3.
3 I/O Connector Connection to component handler. 36 pin
Amp connector, mates with Amp 552302-1
plug and 552073-5 strain relief cover or
ribbon cable clamp connector 553600-1 or
equivalents. Refer to paragraph 2.7.1.
4 Parallel Port Connection to parallel printer. Type
DB25 (25 pin) female connector. Refer to
paragraph 2.7.2.
5 RS232 Connector Connection according to RS232 std
interface. Type DB9 (9 pin) male
connector. Refer to paragraph 2.7.4.
Introduction 1-4
Table 1-2 (continued)
Rear Panel Connectors and Controls
Figure 1-3
Ref. No. Item Function
6 ! Bias Voltage External bias input, maximum of
+/-200Vdc. Contains F0.25A, 250V,
5x20mm fast blow fuse. Replace only with
the same type and rating. Also refer to
paragraph 2.6.2.5.
7 Battery DC source for backup of system memory,
3 standard alkaline AA batteries which
should be replaced annually (Refer to
paragraph 4.3.1)
1.4 Accessories Included
Table 1-3
Item Quantity
Instruction Manual 1
Calibration Certificate 1
Power Cord (CE units with international cord set) 1
Fuse (T2.5A, 250V, 5x20mm, for 115/220V operation) 1
1.5 Accessories/Options Available
Table 1-4
Item Part Number
Rack Mount Kit 7000-00
BNC Cable Set, 1 meter 7000-01
BNC Cable Set, 2 meters 7000-02
Kelvin Clip Leads 7000-03
Alligator Clip Leads 7000-04
Clip Component Tweezers 7000-05
Low Voltage Axial/Radial Lead Component Test Fixture 7000-06
Low Voltage Chip Component Test Fixture 7000-07
High Voltage Test Fixture 7000-08
Calibration Kit 7000-09
Introduction 1-5
1.6 Installation
1.6.1 Instrument Positioning
The 7600 contains a high resolution back lit LCD for convenient viewing. The optimum
angle for viewing is straight onto the display. This means that for bench operation the
front bail should sometimes be used to angle the instrument up and for rack installation it
should be mounted somewhat at eye level.
1.6.2 Power Requirements
!
The 7600 Precision LCR Meter can be operated from a power source between 90
and 250Vac at a power line frequency of 47 to 63Hz, no line voltage switching is
necessary. Power connection to the rear panel is through an ac inlet module comprised of
an ac connector and fuse drawer. Before connecting the 3-wire power cord between the
unit and AC power the fuse should be in accordance with the power source, T2.5A,
250V, 5x20mm (QuadTech PN 520049) for 115 or 220V source. Always use an outlet
that has a properly connected protection ground. The 7600 is factory shipped with the
2.5A fuse in place. The instrument can be damaged if the wrong fuse is installed.
To change the fuse proceed as follows:
WARNING
MAKE SURE THE UNIT HAS BEEN DISCONNECTED FROM ITS AC POWER
SOURCE FOR AT LEAST FIVE MINUTES BEFORE PROCEEDING.
Fuse drawer wi t h release tab
Introduction 1-6
90 - 250 V
47 - 63 Hz
40 WATTS M AX
IEEE- 488 INT ERF ACE
PARALL EL POR T RS-232 I NT ERF ACE
I/O PO R T
Figure 1-4
Fuse Drawer
BIAS VO LT AG E
200V M AX
+
BAT TERY
-
• Remove the fuse drawer by inserting a small flat head screwdriver behind the small
tab to force the draw outward. Refer to Figure 1-4.
• Once the fuse drawer has been completely removed from the instrument remove the
clear fuse tray from the drawer by lifting upward slightly on the long narrow black
locking tab. This will allow the fuse tray to be removed from the fuse drawer. This
tray contains the active fuse, left side (secured by holder) and spare fuse on the right
side (if present). Refer to Figure 1-5.
• Remove the active fuse from the holder by prying upward using a small flat head
screwdriver. Insert the replacement fuse into the fuse holder.
• Once the fuse has been installed in the holder and spare fuse (if desired) installed in
the right side of the tray insert the tray back into the fuse drawer, push in and lock.
The two silver contacts on the fuse tray should be positioned towards the outside.
• Once the fuse tray has been installed in the draw, reinstall the fuse drawer back into
the instrument ac inlet module, push in and lock.
Active fuse in holder
this side
Contacts
Spare
fuse
Locking
tab
this
side
Figure 1-5
Fuse Drawer
1.6.3 Safety Inspection
!
Before operating the instrument inspect the power inlet module on the rear of the
7600 to ensure that the properly rated fuse is in place, otherwise damage to unit is
possible. Refer to paragraph 1.6.2.
The 7600 is shipped with a standard U.S. power cord, QuadTech PN 4200-0300 (with
Belden SPH-386 socket or equivalent, and 3 wire plug conforming to IEC 320) and CE
units with an approved international cord set. Make sure the instrument is only used with
these cables (or other approved international cord set) that ensures the instrument is
provided with connection to protective earth ground.
Introduction 1-7
When the 7600 is used in a rack installation (using the QuadTech 7000-00 Rack Mount
Kit) make sure the unit is secured using the cabinet mounting rails and not secured
solely by the front panel angle brackets.
In bench or rack mount applications the instrument should be positioned with
consideration for ample airflow to the rear panel fan ventilation holes. An open space of
at least 3 inches (75mm) is recommend behind the rear panel. The surrounding
environment should be free from excessive dust to prevent contamination of electronic
circuits.
WARNING
If this instrument is used in a manner not specified in this manual protection to the
operator and equipment may be impaired.
Introduction 1-8
Section 2 Operation
2.1 General
Once the 7600 is powered up it is ready immediately for testing, at default test
conditions, by pressing the START button. Power-up default conditions are discussed
in paragraph 2.5.2. Any of these conditions and all other instrument operations can be
changed by easy-to-use menu functions, for simplicity of understanding, descriptions and
uses of all these functions refer to menu discussions in paragraph 2.6. The Contents list
in the front of this manual should be used for quickly locating specify subjects of interest.
NOTE:
For optimum measurement results at specified accuracy a 30 minute instrument
warm-up period is highly recommended.
2.2 Startup
Connect the instrument power cord to the source of proper voltage. The instrument is
to be used only with three-wire grounded outlets. The proper fuse must be installed
as described in paragraph 1.6.2.
Power is applied to the 7600 by pressing the POWER button on the front panel. The
instrument runs a self test and any error messages are displayed accordingly.
2.3 Connection to Device Under Test
The 7600 unit employs a four terminal measurement configuration that permits easy,
accurate and stable measurements and avoids mutual inductance, interference from
measurement signals, noise and other factors inherent with other types of connections.
To help maintain measurement integrity QuadTech makes available a number of
accessory cable sets and fixtures for connection directly to the front panel BNC
connectors. Refer to paragraph 1.5 for a list of available accessories.
Operation 2-1
51 ohms 7600
IH PH PL ILGround
7600
Precision
LCR Meter
!
CAUTION
HIGH VOLTAGE
IL IH
PL PH
+-
DUT
Figure 2-1 Figure 2-2
Panel Layout Test Lead Configuration
Figures 2-1 and 2-2 show the 7600 connector configuration and a typical four terminal
connection to the device under test. H and L on the 7600 denote polarity of AC test
signal at the measurement terminals as well as + and - polarity of DC bias voltage
when applied to the DUT. Refer to paragraph 2.8 for information on operation and
connection of QuadTech accessory cables and fixtures.
WARNING
When DC bias is applied, the PH connection carries a positive DC voltage with
respect to ground.
2.4 Zeroing
Before making measurements, the 7600 should be zeroed to correct for test lead and/or
fixture errors. During the zeroing process corrections are calculated and stored in
instrument memory and applied to ongoing measurements. Measurement accuracy is
specified at the end of the QuadTech one meter cable (7000-01). Open and short circuit
zeroing should be done at the end of this cable. In order to maintain instrument accuracy
with other cable lengths the instrument should be re calibrated using the QuadTech 700009 Calibration Kit and the alternate cable. Generally the unit should be zeroed at least
once per day and each time test leads or fixture is changed. It is not necessary to re-
zero if the test frequency is changed. The zeroing routine is accessed through the
Utilities Menu as follows:
• Press MENU key
• Press LEFT/RIGHT ARROW to select Utilities menu
• Press UP/DOWN ARROW key for Open / Short
• Press ENTER
For guarded measurements
connect to DUT shield
Operation 2-2
Follow the instructions shown on the LCD display for open and short circuit zeroing of
test leads and/or fixture. During the Open Test the leads or fixture should be open with
no component connected. During the Short Test leads should be connected or fixture
shorted (using a clean copper wire, as short as possible). Refer to paragraph 2.6.5.4 as
necessary for more detail. When zeroing, Contact Check should be OFF, # to Average
to 1 and Median OFF.
2.5 Measurement Procedure
2.5.1 General
Whenever the 7600 is powered up it is ready immediately to begin measuring at
default test conditions. Initially, these conditions will be set to factory default but can
be changed by the user and stored to overwrite factory default. To initiate a test once a
device is connected press START, the LCD display shows the measured results and test
conditions similar to the illustration of Figure 2-3. For information on changing test
conditions refer to paragraph 2-6 on Menu Functions.
NOTE:
For optimum measurement results at specified accuracy a 30 minute instrument
warm-up period is highly recommended.
Measured Parameters
Voltage
RETST
pFCs 17.52510
DF
Freq
Range
Delay
2.5.2 Default Measurement Conditions
A set of default measurement conditions are initially established at the factory and stored
in instrument memory. Default conditions are those that determine the instruments status
on power up, thus the instrument is always set to a known state before any testing begins.
These conditions can be changed by the user for tailoring to a specific application. Refer
to paragraph 2.6.5.1 under Save Setup on the Utilities menu.
0.0000500
1.0000kHz
Auto
Figure 2-3
Measured Results Display
AC Signal
Average
Bias
1.000V
1
Off0 ms
Operation 2-3
Factory default measurement conditions are:
Under Setup Menu
Primary Parameter - Auto
Secondary Parameter - None
Frequency - 1 kHz
AC Test Signal - 1V
DC Bias Voltage - Off
Range Hold - Off
Range Locked - 0
Measurement Accuracy - Medium
Delay Time - 0
# to Average - 1
Contact Check - Off
Under I/O Menu
Display Type - Measured Parameters
Nominal Value - None
Result Format - Engineering
Trigger - External
Handler - On
RS-232 - Disable
IEEE - Disable
Print Results - Off
Results to Floppy - Off
Under Analysis Menu
Binning - None
Test Sequencing - Off
Parameter Sweep - Off
Median - Off
Distort Detect - On
Load Correction - Off
Under Utilities Menu
Lockout - Off
Backlite - On
Operation 2-4
2.6 Menu Functions
2.6.1 General
All programmable functions of the Model 7600 are controlled by easy to use menu
displays. The user enters the menu mode by selecting the MENU key which calls up four
top level menus, Setup, I/O, Analysis and Utilities. Each one of these is comprised of a
sub menu list whose functions are described in detail below. Finding ones way around
the menu listing is accomplished in a fashion similar to an Automatic Teller Machine
(ATM) using the UP, DOWN, RIGHT and LEFT arrow keys as indicated on the
adjacent LCD display. A highlighted menu function can be controlled by selecting
the ENTER key, making the desired entry or selection and pressing ENTER again
to implement.
2.6.2 Setup Menu
Setup
Primary Parameter
Secondary Parameter
Frequency
AC Test Signal
DC Bias Voltage
Range Hold Off On
Range Locked = 0
Measurement Accuracy
Measurement Delay
# to Average
Contact Check
I/0 Utilities
(ms)
Analysis
= 1.0000 kHz
Off
= 0
= 1
Off
Int
On
>>
>>
>>
Ext
>>
Figure 2-4
Setup Menu
The first of the four main menus is Setup, shown above. Each function controls a 7600
measurement condition and is described in detail below.
Operation 2-5
Setup I/O Analysis Utilities
Primary Parameter
Secondary Parameter
Frequency - (numeric entry)
AC Test Signal
- Voltage
- Current
- Value - (numeric entry)
DC Bias Voltage
- Off
- Int
- Ext
- OffRange Hold
- On
Range Locked - (numeric entry)
Measurement Accuracy
- Fast
- Medium
- Slow
Measurement Delay - (numeric entry)
# to Average - (numeric entry)
None
DF
Q
|ESR|
θ
Rs
Rp
Gp
Cs
Cp
Ls
Lp
|Z|
|Y|
Xs
Bp
Auto
Cs
Cp
Ls
Lp
Rs
Rp
DF
Q
|Z|
|Y|
θ
|ESR|
Gp
Xs
Bp
Contact Check - Off
- On
2.6.2.1 Primary Parameter
Analysis
Pri Param
I/0 UtilitiesSetup
Auto
Cs
Cp
Ls
Lp
Rs
Rp
DF
Q
|Z|
|Y|
(more)
HIT MENU TO RETURN TO MAIN MENU
Figure 2-5
Primary Parameters
Additional Parameters not shown and selected by UP/DOWN arrow keys include: θ,
|ESR|, Gp, Xs, Bp
Operation 2-6
Any combination of two parameters can be measured and displayed simultaneously on
the 7600, one referred to as the Primary (displayed first) and the other the Secondary.
The instrument as powered up provides a default primary parameter selection of Auto, a
feature which enables any passive component to be measured without knowing what type
of component it is. Depending on the component type the primary and secondary default
could be Cs & DF, Rs & Q, or Ls & Q. The parameter selection can be chosen by the
operator through menu selection as shown in Figure 2-5 above. Besides Auto the
following selections are possible and discussed in more detail below.
Cs - Capacitance in farads |Z| - Impedance in ohms
Cp - Capacitance in farads |Y| - Admittance in siemens
Ls - Inductance in henries θ - Angle in degrees
Lp - Inductance in henries |ESR|-Equivalent series resistance in ohms
Rs - Resistance in ohms Gp - Conductance in siemens
Rp - Resistance in ohms Xs - Reactance in ohms
DF- Dissipation Factor (no units) Bp - Susceptance in siemens
Q - Quality Factor (no units)
s = series equivalent circuit
p = parallel equivalent circuit
An impedance that is neither a pure resistance nor a pure reactance can be represented at
any specific frequency by either a series or a parallel combination of resistance and
reactance. Such a representation is called an equivalent circuit. The value of the primary
measurement of a device depends on which equivalent circuit, series or parallel, is
chosen to represent it. The manufacturer or user of a device specifies how a device is to
be measured (usually series) and at what frequency. If this is not known, be sure to
specify if the results were series or parallel and what the measurement frequency was.
Series and parallel equivalent circuits for a lossy inductor and lossy capacitor are shown
in Figure 2-6.
Operation 2-7
Rs
Cs
Cp
Rp or
Gp
Rs
Lp
Ls
Figure 2-6
Series and Parallel Circuits for both Capacitive and Inductive Impedances
Impedance is the parameter used to characterize electronic components, materials and
circuits. Impedance |Z| is defined as the opposition a device or circuit offers to the flow
of ac current at a particular frequency and generally represented as a complex quantity
consisting of a real part (resistance, R) and imaginary part (reactance, jX). Impedance
can be expressed using the rectangular coordinate form (R + jX) or polar form as
magnitude and phase angle (|Z| ∠θ). Figure 2-7 shows the mathematical relationship
between R, X, |Z|, and θ for both inductive and capacitive devices. In some cases it
becomes mathematically practical to represent impedance using the reciprocal where
1/|Z| = |Y| = G + jB, where |Y| represents admittance, G conductance, and B susceptance.
This mathematical relationship is shown in Figure 2-8 for inductive and capacitive
devices.
+jX
Rs
+R
θ
δ
+j Lsω
δ
Z
Rp or
Gp
ω-j/ Cs
-jX
Operation 2-8
Z
Impedance
-jXRs
Figure 2-7
Phase Diagrams of Impedance
θ
InductanceCapacitance
+R
j
InductanceCapacitance
+jB
+jB
Gp
Cpω
Y
φ
+G
δ
δ
φ
+G
-j/ Lpω
Y
Gp
-jB
-jB
Admittance
Figure 2-8
Phase Diagrams of Admittance
Quality factor (Q) is used as a measure of a reactance's purity (how close it is to being a
pure reactance, i.e. no resistance) and defined as the ratio of the energy stored in a device
to the energy dissipated by the device. Q is dimensionless and is expressed as Q = X/R =
B/G. From Figure 2-8 one can see that Q is the tangent of the angle θ. Q is commonly
applied to inductors and for capacitors the term generally used to express purity is
Dissipation Factor (D), which is the reciprocal of Q.
Any parameter, primary or secondary, can be chosen as the default parameter at power
up, refer to paragraph 2.6.5.1, changing default conditions.
2.6.2.2 Secondary Parameter
Sec Param
I/0 UtilitiesSetup
None
DF
Q
ESR
θ
Rs
Rp
Gp
Cs
Cp
Ls
(more)
HIT MENU TO RETURN TO MAIN MENU
Analysis
Figure 2-9
Secondary Parameter
Operation 2-9
Additional Parameters not shown and selected by UP/DOWN arrow keys include: Lp,
|Z|, |Y|, Xs, Bp
As in the primary parameter selection, any one parameter can be chosen by the operator
for display. The instrument as powered up provides a default secondary parameter.
When the default primary parameter is Auto the secondary parameter is dependent and
determined by it. If the primary default is Cs the secondary defaults to D. If the primary
default is Ls or Rs the secondary defaults to Q. The parameter selection can be chosen by
the operator through menu selection as shown in Figure 2-9.
2.6.2.3 Frequency
Numerical entry accepts up to five digits with decimal, of the desired test frequency
between 10 Hz and 2 MHz. Resolution of setting is 0.1 Hz from 10 Hz to 10 kHz, 5
digits above 10 kHz and 4 digits above 100 kHz. The accuracy of the frequency
programmed is +/- (0.25% + 0.02 Hz).
Units of frequency, Hz, kHz, or MHz are selected by the UP/DOWN arrow keys.
NOTE:
In order for the instrument to perform high frequency measurements (i.e. above 50 kHz),
frequencies are grouped into ranges. The size of these ranges is dependent upon many
factors: including the DDS clock frequency, the frequency programmed, and the
frequency accuracy resolution specified for the unit. Thus when a user programs a "test
frequency" the actual frequency may be +/- (0.25% + 0.02 Hz).
Operation 2-10
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