Keithley Instruments, Inc. warrants this product to be free from defects in material and workmanship for a period of 1 year from
date of shipment.
Keithley Instruments, Inc. warrants the following items for 90 days from the date of shipment: probes, cables, rechargeable batteries, diskettes, and documentation.
During the warranty period, we will, at our option, either repair or replace any product that proves to be defective.
To exercise this warranty, write or call your local Keithley representative, or contact K eithle y headquarters in Cleveland, Ohio. Y ou
will be given prompt assistance and return instructions. Send the product, transportation prepaid, to the indicated service facility.
Repairs will be made and the product returned, transportation prepaid. Repaired or replaced products are warranted for the balance
of the original warranty period, or at least 90 days.
LIMITATION OF WARRANTY
This warranty does not apply to defects resulting from product modification without Keithley’s express written consent, or misuse
of any product or part. This warranty also does not apply to fuses, software, non-rechargeable batteries, damage from battery leakage, or problems arising from normal wear or failure to follow instructions.
THIS WARRANTY IS IN LIEU OF ALL OTHER WARRANTIES, EXPRESSED OR IMPLIED, INCLUDING ANY IMPLIED
WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR USE. THE REMEDIES PROVIDED HEREIN
ARE BUYER’S SOLE AND EXCLUSIVE REMEDIES.
NEITHER KEITHLEY INSTRUMENTS, INC. NOR ANY OF ITS EMPLOYEES SHALL BE LIABLE FOR ANY DIRECT,
INDIRECT, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OF ITS INSTRUMENTS AND SOFTWARE EVEN IF KEITHLEY INSTRUMENTS, INC., HAS BEEN ADVISED IN ADVANCE OF THE POSSIBILITY OF SUCH DAMAGES. SUCH EXCLUDED DAMAGES SHALL INCLUDE, BUT ARE NOT LIMITED TO: COSTS
OF REMOVAL AND INSTALLATION, LOSSES SUSTAINED AS THE RESULT OF INJURY TO ANY PERSON, OR DAMAGE TO PR OPERTY.
All rights reserved.
Cleveland, Ohio, U.S.A.
First Printing, May 1999
Document Number: 7016A-901-01 Rev. A
Manual Print History
The print history shown below lists the printing dates of all Revisions and Addenda created for this manual. The Revision
Level letter increases alphabetically as the manual undergoes subsequent updates. Addenda, which are released between Revisions, contain important change information that the user should incorporate immediately into the manual. Addenda are numbered sequentially. When a new Revision is created, all Addenda associated with the previous Revision of the manual are
incorporated into the new Revision of the manual. Each new Revision includes a revised copy of this print history page.
Revision A (Document Number (7016A-901-01)....................................................................................May 1999
All Keithley product names are trademarks or registered trademarks of Keithley Instruments, Inc.
Other brand and product names are trademarks or registered trademarks of their respective holders
Safety Precautions
The following safety precautions should be observed before using
this product and any associated instrumentation. Although some instruments and accessories would normally be used with non-hazardous voltages, there are situations where hazardous conditions
may be present.
This product is intended for use by qualified personnel who recognize shock hazards and are familiar with the safety precautions required to avoid possible injury. Read the operating information
carefully before using the product.
The types of product users are:
Responsible body is the individual or group responsible for the use
and maintenance of equipment, for ensuring that the equipment is
operated within its specifications and operating limits, and for ensuring that operators are adequately trained.
Operators use the product for its intended function. They must be
trained in electrical safety procedures and proper use of the instrument. They must be protected from electric shock and contact with
hazardous live circuits.
Maintenance personnel perform routine procedures on the product
to keep it operating, for example, setting the line voltage or replacing consumable materials. Maintenance procedures are described in
the manual. The procedures explicitly state if the operator may perform them. Otherwise, they should be performed only by service
personnel.
Service personnel are trained to work on live circuits, and perform
safe installations and repairs of products. Only properly trained service personnel may perform installation and service procedures.
Users of this product must be protected from electric shock at all
times. The responsible body must ensure that users are prevented
access and/or insulated from every connection point. In some cases,
connections must be exposed to potential human contact. Product
users in these circumstances must be trained to protect themselves
from the risk of electric shock. If the circuit is capable of operating
at or above 1000 volts, no conductive part of the circuit may be
exposed.
As described in the International Electrotechnical Commission
(IEC) Standard IEC 664, digital multimeter measuring circuits
(e.g., Keithley Models 175A, 199, 2000, 2001, 2002, and 2010) are
Installation Category II. All other instruments’ signal terminals are
Installation Category I and must not be connected to mains.
Do not connect switching cards directly to unlimited power circuits.
They are intended to be used with impedance limited sources.
NEVER connect switching cards directly to AC mains. When connecting sources to switching cards, install protective devices to limit fault current and voltage to the card.
Before operating an instrument, make sure the line cord is connected to a properly grounded power receptacle. Inspect the connecting
cables, test leads, and jumpers for possible wear, cracks, or breaks
before each use.
For maximum safety, do not touch the product, test cables, or any
other instruments while power is applied to the circuit under test.
ALWAYS remove power from the entire test system and discharge
any capacitors before: connecting or disconnecting cables or jumpers, installing or removing switching cards, or making internal
changes, such as installing or removing jumpers.
Exercise extreme caution when a shock hazard is present. Lethal
voltage may be present on cable connector jacks or test fixtures. The
American National Standards Institute (ANSI) states that a shock
hazard exists when voltage levels greater than 30V RMS, 42.4V
peak, or 60VDC are present. A good safety practice is to expect
that hazardous voltage is present in any unknown circuit bef ore
measuring.
Do not touch any object that could provide a current path to the
common side of the circuit under test or power line (earth) ground.
Always make measurements with dry hands while standing on a
dry, insulated surface capable of withstanding the voltage being
measured.
The instrument and accessories must be used in accordance with its
specifications and operating instructions or the safety of the equipment may be impaired.
Do not exceed the maximum signal levels of the instruments and accessories, as defined in the specifications and operating information, and as shown on the instrument or test fixture panels, or
switching card.
When fuses are used in a product, replace with same type and rating
for continued protection against fire hazard.
Chassis connections must only be used as shield connections for
measuring circuits, NOT as safety earth ground connections.
If you are using a test fixture, keep the lid closed while power is applied to the device under test. Safe operation requires the use of a
lid interlock.
If a screw is present, connect it to safety earth ground using the
wire recommended in the user documentation.
!
The symbol on an instrument indicates that the user should refer to the operating instructions located in the manual.
The symbol on an instrument shows that it can source or measure 1000 volts or more, including the combined effect of normal
and common mode voltages. Use standard safety precautions to
avoid personal contact with these voltages.
The WARNING heading in a manual explains dangers that might
result in personal injury or death. Alw ays read the associated infor mation very carefully before performing the indicated procedure.
The CAUTION heading in a manual explains hazards that could
damage the instrument. Such damage may invalidate the warranty.
Instrumentation and accessories shall not be connected to humans.
Before performing any maintenance, disconnect the line cord and
all test cables.
To maintain protection from electric shock and fire, replacement
components in mains circuits, including the power transformer, test
leads, and input jacks, must be purchased from Keithley Instruments. Standard fuses, with applicable national safety approvals,
may be used if the rating and type are the same. Other components
that are not safety related may be purchased from other suppliers as
long as they are equivalent to the original component. (Note that selected parts should be purchased only through Keithley Instruments
to maintain accuracy and functionality of the product.) If you are
unsure about the applicability of a replacement component, call a
Keithley Instruments office for information.
To clean an instrument, use a damp cloth or mild, water based
cleaner. Clean the exterior of the instrument only. Do not apply
cleaner directly to the instrument or allow liquids to enter or spill
on the instrument. Products that consist of a circuit board with no
case or chassis (e.g., data acquisition board for installation into a
computer) should never require cleaning if handled according to instructions. If the board becomes contaminated and operation is affected, the board should be returned to the factory for proper
cleaning/servicing.
Rev. 2/99
7016A 50Ω2GHz Multiplexer
MULTIPLEXERS PER CARD: 2 (with isolated ground).
CHARACTERISTIC IMPEDANCE: 50Ω nominal.
CHANNELS PER MULTIPLEXER: 4.
CONTACT CONFIGURATION: 1 pole Form A common shield.
RELAY DRIVE CURRENT: 120mA.
CONNECTOR TYPE: SMA.
RECOMMENDED CABLE: RG-223/U.
TERMINATION: User supplied 50ΩSMB termination (on unselected
inputs).
ACTUATION TIME: 8ms.
MAXIMUM VOLTAGE: Any terminal (center or shield) to any other
center or chassis: 30V.
MAXIMUM CARRY CURRENT: 0.5A.
MAXIMUM CARRY POWER: 10VA up to 900MHz, 3VA @ 2GHz.
ISOLATION:
Multiplexer to Multiplexer: >1GΩ.
Center to Shield:>1GΩ, <50pF.
Channel to Channel:>100MΩ.
RISE TIME: <200ps.
SIGNAL DELAY: <3ns; channels matched to 50ps.
CONTACT POTENTIAL: <6µV.
CONTACT RESISTANCE: 0.5Ω.
5
CONTACT LIFE: 3×10
@ 30V @ 10mA.
5
@ 900MHz, 1W.
3×10
6
@ cold switching.
1×10
ENVIRONMENT: Operating: 0° to 50°C; up to 35°C at 80% RH.
Storage: –25°C to 65°C.
EMC: Conforms with European Union Directive 89/336/EEC.
SAFETY: Conforms with European Union Directive 73/23/EEC.
AC PERFORMANCE:
For ZL= Z
= 50ΩMHzMHzMHzGHzGHz
S
≤10≤100≤500≤1≤2
Insertion Loss (dB):<0.3<0.6<1.0<1.3<3.0
Crosstalk (dB):
Channel-Channel<–90<–80<–65<–55<–45
1
Switch-Switch<–90<–80<–70<–65<–45
VSWR<1.06<1.1<1.2<1.6≤1.9
1
Specification assumes 50Ω termination.
LOG MAGNITUDE0.500 dB/DIVREF= 0.000dB
0.0dB
–1.5dB
0.00.40.81.21.62.0
SWR150.000 mU/DIVREF= 1.000U
1.75:1
1.00:1
0.00.40.81.21.62.0
7016A Channel-to-Channel Crosstalk, Typical
LOG MAGNITUDE10.000 dB/DIVREF= -20.000dB
–20dB
–60dB
7016A Insertion Loss, Typical
GHz
7016A VSWR, Typical
GHz
SMA
Connector
SMB
Connector
Ch. 1
Ch. 2
Out
Ch. 3
Ch. 4
Ch. 5
Ch. 6
Out
Ch. 7
Ch. 8
0.00.40.81.21.62.0
GHz
TYPICAL: Typical but not warranted parameter, intended to provide useful information for switch application.
1.3Warranty information ..........................................................................................................................................1-1
1.5Safety symbols and terms ...................................................................................................................................1-1
1.7Unpacking and inspection ...................................................................................................................................1-2
1.7.1Inspection for damage................................................................................................................................1-2
1.9Repacking for shipment .......................................................................................................................................1-2
2.4Card installation and removal ..............................................................................................................................2-4
3.3.1Closing and opening channels....................................................................................................................3-1
3.4IEEE-488 bus control...........................................................................................................................................3-2
3.4.1Closing and opening channels....................................................................................................................3-2
4.2Handling and cleaning precautions...................................................................................................................... 4-1
4.3.3Insertion loss tests...................................................................................................................................... 4-2
4.3.5Special handling of static-sensitive devices .............................................................................................. 4-7
4.4Principles of operation......................................................................................................................................... 4-7
5.2Parts list ............................................................................................................................................................... 5-1
Figure 2-5Card installation in Model 7001...................................................................................................................2-5
Figure 2-6Card installation in Model 7002...................................................................................................................2-6
Figure 4-1Connections for insertion loss tests..............................................................................................................4-3
Figure 4-2Connections for channel isolation tests........................................................................................................4-4
Figure 4-3Connections for center-to-shield isolation tests...........................................................................................4-5
Figure 4-4Connections for multiplexer-to-multiplexer isolation tests..........................................................................4-6
Table 4-2Insertion loss values.....................................................................................................................................4-2
Table 5-1Model 7016A parts list.................................................................................................................................5-2
v
1
General Information
1.1Introduction
This section contains general information about the Model
701A6 50 Ω 2GHz Multiplexer Card. The Model 7016A is
equipped with two four-channel multiplexers and is designed
for 50 Ω operation. Provisions for user-supplied 50 Ω terminators are provided on the card.
1.2Features
Key Model 7016A features include:
• T w o independent multiplex ers each with four channels.
•50 Ω characteristic impedance.
• Provisions for user-supplied SMB terminators to maintain nominal 50 Ω characteristic impedance for off
channels.
• 2GHz bandwidth.
• Low insertion loss (<3dB @ 2GHz).
• Low VSWR assures good high-frequency performance.
1.4Manual addenda
Any improvements or changes concerning the card or manual will be explained in an addendum included with the card.
1.5Safety symbols and terms
The following symbols and terms may be found on an instrument or used in this manual.
!
Thesymbol on equipment indicates that you should refer to the operating instructions located in the instruction
manual.
The WARNING heading used in this manual explains dangers that might result in personal injury or death. Always
read the associated information very carefully before performing the indicated procedure.
The CAUTION heading used in this manual explains hazards that could damage the multiplexer card. Such damage
may invalidate the warranty.
1.3Warranty information
Warranty information is located on the inside front cover
of this instruction manual. Should your Model 7016A require warranty service, contact the Keithley representati ve
or authorized repair facility in your area for further information. When returning the card for repair, be sure to fill
out and include the service form at the back of this manual
in order to provide the repair facility with the necessary information.
1.6Specifications
Model 7016A specifications are located at the front of this
manual.
1-1
General Information
1.7Unpacking and inspection
1.7.1Inspection for damage
The Model 7016A is packaged in a re-sealable, anti-static
bag to protect it from damage due to static discharge and
from contamination that could degrade its performance. Before removing the card from the bag, observe the precautions
on handling discussed below.
1.7.2Handling precautions
• Always grasp the card by the side edges and covers. Do
not touch the board surfaces or components.
• After removing the card from its anti-static bag, inspect
it for any obvious signs of physical damage. Report any
such damage to the shipping agent immediately.
• When the card is not installed in a switching mainframe, keep the card in its anti-static bag, and store it in
the original packing carton.
1.7.3Shipment contents
1.9Repacking for shipment
Should it become necessary to return the Model 7016A for
repair, carefully pack the unit in its original packing carton
or the equivalent, and include the following information:
• Advise as to the warranty status of the card.
• Write ATTENTION REPAIR DEPARTMENT on the
shipping label.
• Fill out and include the service form located at the back
of this manual.
1.10Recommended accessories
Recommended cables and terminating resistors are covered
below. These items are not stocked by Keithley and must be
obtained from other sources.
1.10.1 Connecting cables
The following cable type is recommended for making input/
output connections to the Model 7016A: RG223/U.
The following items are included with every Model 7016A
order:
• Model 7016A 50 Ω 2GHz Multiplexer Card
• Model 7016A Instruction Manual
• Additional accessories as ordered
1.8Instruction manual
If an additional Model 7016A Instruction Manual is required, order the manual package, Keithley part number
7016A-901-00. The manual package includes an instruction
manual and any pertinent addenda.
Other 50 Ω cables may be used, but keep in mind key parameters as such as maximum outside diameter, attenuation ov er
the desired frequency range, flexibility, and shield type. See
paragraph 3.5 in Section 3 for more information on cable parameters.
1.10.2 Terminating resistors
The following terminating resistor is recommended for use
with the Model 7016A:
Type: Plug Dummy Load
Manufacturer: Johnson Components
Part number: 131-3801-811
Nominal resistance: 50 Ω
Power dissipation: 2W
1-2
2
Connections and Installation
2.1Introduction
WARNING
The procedures in this section are intended only for qualified service personnel. Do not perform these procedures
unless you are qualified to do so. Failure
to recognize and observe normal safety
precautions could result in personal injury or death.
This section includes information on making connections to
the Model 7016A and installing the card in the Model 7001/
7002 Switch System.
2.2Handling precautions
To maintain high-impedance isolation between channels,
care should be taken when handling the card to avoid contamination from such foreign materials as body oils. Such
contamination can reduce isolation resistance. To avoid possible contamination, always grasp the card by the side edges
or covers. Do not touch board surfaces, components, or connector insulators.
Dirt build-up over a period of time is another possible source
of contamination. To avoid this problem, operate the card in
a clean environment. If the card becomes contaminated, it
should be thoroughly cleaned as explained in paragraph 4.2.
2.3Connections
This paragraph provides the information necessary to connect your external test circuitry to the Model 7016A.
2.3.1Simplified schematic
Figure 2-1 shows a simplified schematic diagram of the
Model 7016A. The card is arranged into two separate multiplexers, each with four channels.
2.3.2Card configuration
Figure 2-2 shows the general configuration of the Model
7016A. Connectors include:
IN 1-8 (channels 1-8): Each input is equipped with an SMA
coaxial connector. The center conductor is the signal path,
while the outer shell connected to signal common.
OUT A and OUT B: Each multiplexer is equipped with an
SMA coaxial connector. The center conductor is the signal
path, and the shell is connected to signal common.
Termination jacks: Each channel has an SMB coaxial ter-
minator jack. User-supplied 50 Ω terminators can be connected to these jacks when a 50 Ω nominal input impedance
must be maintained for off channels.
2-1
Connections and Installation
SMA
Connector
SMB
Connector
A
A
A
A
B
B
B
Ch. 1
Ch. 2
Out A Multiplexer A
Ch. 3
Ch. 4
A
Ch. 5
Ch. 6
Out B Multiplexer B
Ch. 7
Figure 2-1
Model 7016A simplified schematic
Figure 2-2
Model 7016A configuration
Multiplexer B
SMB Terminator
Connectors
7
5
Multiplexer B
SMA Input/Output
8
6
Connectors
Ch. 8
B
B
Multiplexer A
SMB Terminator
Connectors
3
1
2
4
Multiplexer A
SMA Input/Output
Connectors
2-2
Figure 2-3
Typical connection scheme
50 Ω
Connections and Installation
2.3.3Input/output connecting cables
All connections to the scanner card input and output jacks
should be made using 50 Ω coaxial cable equipped with
SMA connectors. The recommended cable type is RG223/U.
WARNING
Make sure that power is off and external
energy sources are discharged before connecting or disconnecting cables.
NOTE
cables must be used to assure good highfrequency performance. RG223/U should be
used for best performance. See paragraph 3.5
in Section 3 for more information.
A
2.3.4Typical connecting scheme
Figure 2-3 shows a typical connecting scheme for the Model
7016A. In this arrangement, sources are connected to the inputs
while the measuring instrument is connected to the outputs.
CAUTION
Maximum voltage from any terminal (center conductor or shield) to any other terminal or chassis is 30V RMS. Exceeding this
value may result in card damage.
AC
Signals
Ch. 1
Ch. 2
A
A
A
B
B
B
B
Out A
Ch. 3
Ch. 4
A
Note: All cables are 50Ω
Ch. 5
Ch. 6
Out B
Ch. 7
Ch. 8
B
Measuring Instrument
2-3
Connections and Installation
2.3.5Input termination
User-supplied 50 Ω female SMB terminators may be installed for applications requiring proper 50 Ω termination of
off channels. Figure 2-4 shows typical installation of a 50 Ω
terminator. See paragraph 1.10 in Section 1 for recommended terminators. Switching considerations in Section 3 discusses terminator aspects in more detail.
NOTE
Be sure to observe the maximum power
handling capability of installed terminators. The terminators recommended in
Section 1 are limited to 2W even through
the Model 7016A can switch up to 10W.
2.4Card installation and removal
This paragraph explains how to install and remov e the Model
7016A card assembly from the Model 7001/7002 mainframe.
WARNING
Installation or removal of the Model
7016A should be performed only by
qualified service personnel. Failure to
recognize and observe standard safety
precautions could result in personal injury or death.
NOTE
To prevent performance degradation
caused by contamination, handle the card
only by the edges and covers.
Terminator
Figure 2-4
50Ω terminator installation
2-4
Jack
Figure 2-5
Card installation in Model 7001
Connections and Installation
2.4.1Card installation
Perform the following steps, and refer to Figure 2-5 or Figure
2-6 to install the card assembly in the Model 7001/7002
mainframe.
WARNING
Turn off power to all instrumentation
(including the Model 7001/7002), and
disconnect all line cords. Make sure all
power is removed and any stored energy
in external circuitry is discharged.
1. Open the ejector arms at the back edge of the card.
2. Slide the card edges into the guide rails inside the mainframe.
3. Carefully push the card all the way forward until the
ejector arms engage the mounting cups.
4. Push in on the card edge and ejector arms until the card
is properly seated.
5. Make sure the ejector arms are properly latched.
2.4.2Card removal
Follow the steps below to remove the multiplexer card from
the mainframe:
WARNING
Turn off power to all instrumentation
(including the Model 7001/7002), and
disconnect all line cords. Make sure all
power is removed and any stored energy
in external circuitry is discharged.
1. Pull out on the ejector arms until the card pulls free from
the internal connector.
2. Carefully slide the card out of the switching mainframe.
Ejector Arms (2)
Unlock card
Lock card
2-5
Connections and Installation
Ejector Arms
(locked position)
INTERCONNECTION, INSTALLATION AND REMOVAL OF CARDS BY QUALIFIED SERVICE PERSONNEL ONLY.
WARNING:
CARD
1
CARD
2
CARD
3
NO INTERNAL OPERATOR SERVICEABLE PARTS, SERVICE BY QUALIFIED PERSONNEL ONLY.
WARNING:
CARD
4
Figure 2-6
Card installation in Model 7002
2-6
3
Operation
3.1Introduction
This section contains basic information on using the Model
7016A including signal limitations and switching considerations. For detailed mainframe operating information, refer
to the Model 7001 or Model 7002 Instruction Manual.
3.2Signal limitations
CAUTION
To prevent damage to the Model 7016A,
do not exceed the maximum signal level
specifications of the card.
To prevent over-heating or damage to the relays, never exceed the following maximum signal levels when using the
Model 7016A:
• Maximum voltage: Any center conductor or shield to
any other center conductor or to chassis: 30V.
• Maximum current: 0.5A per channel.
• Maximum power: 10VA switched up to 900MHz, 3VA
@ 2GHz.
3.3Front panel control
3.3.1Closing and opening channels
Model 7016A installed in slot 2, key in the following channel
list, and press CLOSE:
SELECT CHANNELS 2!4
To open a closed channel, simply press OPEN or OPEN
ALL.
Channels are organized into two multiplexer banks as follows:
Multiplexer A: channels 1 to 4
Multiplexer B: channels 5 to 8
You can also simultaneously close one channel in each multiplexer by including both channels in the channel list. For
example, to close channels 1 and 5 of a card in slot 1, enter
the following channel list at the prompt:
SELECT CHANNELS 1!1, 1!5
(Note that channels are separated by a comma, which can be
inserted by pressing either the ENTER or right cursor key.)
NOTE
T o maintain 50 Ω characteristic impedance,
close only one channel per multiplexer simultaneously. Closing more than one
channel per multiplexer may cause unexpected results. Program the Model 7001/
7002 for restricted operation to avoid closing more than one channel at a time.
To close a Model 7016A multiplexer channel, simply key in
the CHANNEL assignment (1-8), then press the Model
7001/7002 CLOSE key . F or e xample, to close channel 4 of a
Again, you can open closed channels with the OPEN or
OPEN ALL key. (OPEN opens only channels in the channel
list while OPEN ALL opens all channels.)
3-1
Operation
3.3.2Scanning channels
T o scan through channels, first configure a scan list, then program the Model 7001/7002 to perform a scan sequence. You
can create a scan list in the same manner as you would a
channel list. First, however, press the SCAN LIST key to select the “SCAN CHANNEL” mode, then enter the desired
channels to be included in the scan list. For example, the following list scans channels 1, 3, and 5 through 8 of a Model
7016A installed in slot 2:
SCAN CHANNELS 2!1, 2!3, 2!5-2!8
Note that channels are scanned in the order they appear in the
scan list.
To perform a manual scan, first select the RESET default
conditions in the SAVESETUP menu of the main MENU.
Press STEP to take the mainframe out of the idle state, then
manually scan through channels by pressing the STEP key.
For information on more complex scan sequences, refer to
the Model 7001 or 7002 Instruction Manual.
3.4IEEE-488 bus control
3.4.1Closing and opening channels
Use the following SCPI commands to close and open channels:
:CLOS <list>
:OPEN <list> | ALL
For example, the following command will close channels 2
and 6 of a Model 7016A installed in slot 1:
:CLOS (@ 1!2, 1!6)
Conversely, either of the commands below will open previ-
ously closed channels 2 and 6:
:OPEN (@ 1!2, 1!6)
:OPEN ALL
The *RST command selects the default scan configuration,
while the second command automatically sets the channel
count to the number of channels in the scan list. The
:ROUT:SCAN command programs the scan list, and the
:INIT command takes the mainframe out of the idle state.
For example, send the following commands to scan through
all eight channels of a Model 7016A installed in slot 1:
*RST
:TRIG:SEQ:COUN:AUT ON
:ROUT:SCAN (@ 1!1:1!8)
:INIT
3.5Switching considerations
Signals passing through the Model 7016A 50 Ω 2GHz Multiplexer Card are subject to various ef fects that can influence
their characteristics. The following paragraphs discuss some
of these effects and ways to minimize them.
3.5.1Card characteristics
Insertion loss: Insertion loss indicates signal power lost
while passing through the card. This loss occurs in the various signal path components through the card (connectors,
PC board traces, and relays). The amount of power lost will,
of course, depend on the particular insertion loss specification as well as the applied power . For example, with an inser tion loss of 1dB, and a 10W source signal applied to the card,
about 2W will be dissipated in the card, and approximately
8W will appear at the load. Note that, as with most transmission lines, Model 7016A insertion loss values increase with
increasing frequency.
Capacitance: Model 7016A capacitance values are suffi-
ciently small to be of little concern in most applications. In
some applications (primarily with pulse signals where capacitance can affect rise times), capacitance may be a factor.
Typical Model 7016A center-to-shield capacitance is 50pF.
3.4.2Scanning channels
There are a number of commands associated with scanning.
However, you can perform a simple scan using only the following four commands:
*RST
:TRIG:SEQ:COUN:AUT ON
:ROUT:SCAN <list>
:INIT
3-2
Crosstalk: Crosstalk figures indicate the amount of signal
leakage between channels or switches on the card. W ith similar power levels applied to the various channels, crosstalk
will be of little consequence. With widely different power
levels, however, crosstalk may produced undesired results.
For example, assume that 10W is applied to channel 1, and
1mW is applied to channel 2. Assuming a -55dB crosstalk
figure, the unwanted signal coupled from channel 1 to channel 2 will be only 15dB below the desired channel 2 signal.
):
Operation
VSWR: The term VSWR (Voltage Standing Wave Ratio) is
defined as the ratio of the maximum and minimum voltages
along a transmission path, and it indicates the degree of impedance mismatch. In a perfectly match system, the VSWR
is 1, while open and shorted paths have infinite VSWR values. Since VSWR is related to both the return loss and reflection coefficient, VSWR figures indicate the degree of signal
loss and reflection; the lower the VSWR figure, the less signal attenuation that occurs along the transmission path.
Path isolation resistance: The path isolation resistance is
simply the equivalent resistance between two gi v en connecting points on the card and is of importance primarily for DC
and low-frequency AC signals switched by the card. The effects of this characteristic depend on the particular isolation
specification. Center-to-shield isolation resistance, for example, may cause loading problems with signals having high
source resistance. Channel-to-channel isolation resistance
may result in leakage currents generated in one channel
caused by a voltage source connected to another channel.
3.5.2Cable characteristics
Characteristic impedance (Z
is the value of cable impedance obtained by an RF measurement at either end. For example, a cable with a 50 Ω characteristic impedance is equivalent to a 50 Ω resistor with
sufficient length to connect two components. (The characteristic impedance of a cable depends on the relative diameters
of the inner and outer conductors, as well as on the dielectric
constant of the insulating material.) Since the Model 7016A
is designed to work with 50 Ω cables, you must use 50 Ω cables to assure proper impedance matching. (RG223/U cable
is recommended.) Mismatching anywhere along the transmission path will increase VSWR and signal reflections, decrease return loss, and consequently result in signal
attenuation.
Characteristic impedance
O
power transfer. For example, if a 50 Ω cable is terminated
with 100 Ω , the reflection coefficient is 0.33, the VSWR increases to 2, and the return loss is reduced to less than 10dB.
Proper termination of off channels may also be important in
many cases. For example, a 75MHz source signal will see a
1m open cable as an RF short, a situation that could damage
some equipment. To alleviate such problems, the Model
7016A has provisions for on-card installation of 50 Ω SMB
terminators. (See paragraph 2.3.5 in Section 2 for details on installing terminators.) Be sure to observe the power-handling
capabilities of such terminators as most are limited to substantially less power than the 10W capability of the Model 7016A.
Distributed capacitance: The distributed capacitance of the
cable may be a factor, but generally only for pulse type signals where rise times are a consideration. The recommended
RG223/U cable, for example, has a nominal distributed capacitance of 30.8pF/ft.
Cable connectors: Cable connectors are an obvious necessi-
ty to conveniently make signal connections to various points
in a switching system. While connector designs are optimized for best performance, some small impedance mismatch at connecting points is virtually inevitable. For that
reason, it is considered good practice to minimize the number of connectors used in a transmission path, especially at
higher frequencies.
3.6Applications
The Model 7016A is designed primarily for RF switching
applications at frequencies up to 2GHz. The following paragraphs discuss typical RF applications for the Model 7016A,
including multiplexer expansion, filter testing, and device
impedance testing.
Cable attenuation: Cable attenuation is analogous to inser-
tion loss of the card itself in that it defines the degree of attenuation of the signal as it passes through the cable. Cable
attenuation factors are generally given in dB per 100 ft. and
increase with rising frequency . The recommended RG223/U
cable has attenuation factors of 8.8dB/100 ft. @ 400MHz
and 16.5dB/100 ft. @ 1GHz. Thus, with a 10W, 1GHz signal
applied to 10 ft. of RG223/U, 3.16W will be dissipated in the
cable, and 6.84W will be passed on to the card or load.
Cable termination: Proper cable termination is imperative
to ensure maximum signal transfer and to minimize VSWR
and signal reflections. In the case of Model 7016A operation,
both source and load impedances should be as close to 50 Ω
as possible to assure optimum matching and thus maximum
3.6.1Multiplexer expansion
The simplest way to connect the two Model 7016A multiplexers together for expansion is to use the classic "T" configuration shown in Figure 3-1. Note that this configuration
results in a 1-of-8 multiplexer . Although this configuration is
useful in many applications, the ideal 50 Ω characteristic impedance will not be maintained. Consequently, VSWR will
increase, affecting card insertion loss, particularly at higher
frequencies. Also, considerable transmission path reflections
will occur, an important consideration when switching pulse
signals.
3-3
Operation
Multiplexer
A
Multiplexer
B
A
A
A
A
B
B
B
A
Ch. 1
Ch. 2
Out A
Ch. 3
Ch. 4
"T"
Connector
Ch. 5
Ch. 6
Out B
Ch. 7
Instrument
Note: This configuration
will not maintain
50Ω characteristic
impedance.
Figure 3-1
“T” connector multiplexer expansion
B
Model 7016A
Ch. 8
B
3-4
A
A
Ch. 1
Ch. 2
A
A
Ch. 3
Ch. 4
A
Out A
B
B
Ch. 5
Ch. 6
B
B
Ch. 7
Ch. 8
B
Out B
Short 50Ω
Coax Cable
Multiplexer
A
Multiplexer
B
Instrument Connections
Model 7016A
DUT Connections
A. Connections
Power
Meter
Spectrum
Analyzer
Counter
Network
Analyzer
1
2
3
4
B. 4 x 4 Matrix Configuration
DUTs
Figure 3-2
4 × 4 matrix connections
Operation
The proper way to connect the two Model 7016A multiplexers together is shown in Figure 3-2. Here, the two outputs are
connected together using a short coaxial cable. Note that this
connection scheme effectively forms a 4 × 4 matrix, and it
provides a conv enient way to connect four DUTs to four different test instruments. Also, this method maintains the proper 50 Ω characteristic impedance for optimum bandwidth and
minimal signal loss and reflections.
3-5
Operation
3.6.2Filter testing
Filter frequency response and phase characteristics are key
circuit parameters that often require testing. The Model
7016A may be used in conjunction with a network analyzer
to test multiple filters on an automated basis.
Figure 3-3 shows a typical circuit configuration for testing
four filters. Note that the network analyzer input is connected
to the output of one Model 7016A multiplexers. One terminal of each DUT is connected to a corresponding Model
7016A channel, while the remaining DUT terminals are connected in common to the network analyzer output port.
The basic configuration shown in Figure 3-3 may also be
used for a variety of other tests. For example, the same general scheme may be used to test amplifier S-parameters.
3.6.3Impedance testing
Figure 3-4 shows the general circuit configuration for device
impedance testing using the Model 7016A along with an impedance or LCZ meter, such as a Keithle y Model 3321, 3322,
or 3330. Since 4-wire connections are required for such measurements, two Model 7016A cards are necessary for this application. Each multiplexer switches one of the four required
signal paths to the DUTs.
Since the characteristics of the Model 7016A may affect
measured DUT impedance, steps should be taken to null out
the residual affects of stray capacitance and inductance.
Most LCZ meters have provisions for both open and short
zeroing procedures to minimize these effects. For optimum
accuracy, the zeroing procedure should be carried out independently for each channel.
Figure 3-3
Filter testing
Network Analyzer
IN (PORT 1)OUT (PORT 2)
A
A
A
A
B
B
B
B
Model 7016A
Ch. 1
Filter 1
Ch. 2
Filter 2
Out A
Ch. 3
Filter 3
Ch. 4
A
Ch. 5
Ch. 6
Out B
Ch. 7
Ch. 8
B
Filter 4
3-6
Model
7016A
#1
Operation
A
Ch. 1
Ch. 2
A
Out A
A
Ch. 3
Ch. 4
A
A
B
Ch. 5
Ch. 6
B
Out B
B
Ch. 7
Ch. 8
B
B
DUT
(1 of 4)
LCZ Meter
Figure 3-4
Impedance testing
Model
7016A
#2
L
L
CUR
A
Ch. 1
POTHPOTHCUR
Ch. 2
A
Out A
A
Ch. 3
Ch. 4
A
A
B
Ch. 5
Ch. 6
B
Out B
B
Ch. 7
Ch. 8
B
B
3-7
4
Service Information
4.1Introduction
This section contains information necessary to service the
Model 7016A and includes information on handling and
cleaning, performance verification, as well as principles of
operation and troubleshooting.
WARNING
The information in this section is intended only for qualified service personnel. Some of the procedures may expose
you to hazardous voltages that could result in personal injury or death. Do not
perform these procedures unless you are
qualified to do so.
4.2Handling and cleaning precautions
Because of the high-impedance areas on the Model 7016A,
care should be taken when handling or servicing the card to
prevent possible contamination. The following precautions
should be observed when servicing the card.
• Do not touch areas adjacent to electrical contacts.
• When servicing the card, wear clean cotton gloves.
• Do not store or operate the card in an environment
where dust could settle on the circuit board.
• Use dry nitrogen gas to clean dust off the board if necessary.
4.2.2Soldering considerations
Should it become necessary to use solder on the circuit
board, observe the following precautions:
• Use an OA-based (organic acti v ated) flux, and take care
not to spread the flux to other areas of the circuit board.
• Remove the flux from the work areas when the repair
has been completed. Use pure water along with clean
cotton swabs or a clean soft brush to remove the flux.
• Once the flux has been removed, swab only the repaired
area with methanol, then blow dry the board with dry
nitrogen gas.
• After cleaning, allow the card to dry in a 50°C low-humidity environment for several hours before use.
4.2.1Handling precautions
Observe the following precautions when handling the multiplexer card:
• Handle the card only by the edges and shields.
• Do not touch connector insulators.
• Do not touch any board surfaces or components not associated with the repair.
4.3Performance verification
The following paragraphs provide performance verification
procedures for the Model 7016A. These tests include insertion loss and isolation tests.
4-1
Service Information
4.3.1Environmental conditions
All performance verification measurements should be made
at an ambient temperature of 18°C to 28°C and <70% relative humidity.
4.3.2Recommended verification equipment
Table 4-1 summarizes the test equipment recommended for
performance verification. Alternate equipment may be used
as long as the corresponding specifications are at least as
good as those listed.
4.3.3Insertion loss tests
Insertion loss tests are performed by applying a 10MHz2GHz signal from a network analyzer to the Model 7016A
channel inputs and then measuring the amount of attenuation
as the signal passes through the card.
Proceed as follows:
1. Set the network analyzer to sweep the 10MHz to 2GHz
frequency range.
2. Normalize the analyzer reference channel to 0dB on the
display.
3. Connect the network analyzer to the Model 7016A as
shown in Figure 4-1. Be sure to use 50 Ω cables and setup for all insertion loss tests.
4. Install the Model 7016A in the Model 7001 or 7002
mainframe.
5. Close channel 1 on the Model 7016A card.
6. Verify that the insertion loss values are within the limits
shown in Table 4-2.
7. Open the closed channel.
8. Repeat steps 3 through 7 for channels 2 through 8. For
each channel:
• Connect the analyzer signal to the input jack of the
channel being tested.
• Be sure the signal output cable is connected to the
correct output jack.
• Close the channel being tested.
• Verify that the insertion loss values at the various fre-
quencies are within the limits stated in Table 4-2.
Table 4-2
Insertion loss values
FrequencyInsertion loss
10MHz
100MHz
500MHz
1GHz
2GHz
<0.3dB
<0.6dB
<1dB
<1.3dB
<3dB
4-2
Table 4-1
Recommended verification equipment
DescriptionManufacturer and ModelSpecificationsTest
Network AnalyzerHewlett-Packard 8714ET10MHz-2GHzInsertion loss
ElectrometerKeithley 6517A100MΩ, ±0.151%
1GΩ, ±0.226%
Isolation
Service Information
A
A
A
A
A
B
B
Channel 1 Connections Shown
Ch. 1
Ch. 2
Out A
Ch. 3
Ch. 4
Ch. 5
Ch. 6
Out B
Network Analyzer
OUTPUT INPUT
50Ω Cables
B
B
Ch. 7
Ch. 8
B
Figure 4-1
Connections for insertion loss tests
4.3.4Isolation tests
These tests check the leakage resistance (isolation) between
various Model 7016A terminals using the ohms function of
a Model 6517A Electrometer.
CAUTION
The following tests use the Model 6517A
voltage source to measure resistance. Do
not apply more than 30V to the Model
7016A to avoid card damage.
Channel isolation tests
Perform the following steps to check channel isolation:
1. Connect the Model 6517A Electrometer to the center
conductors of channels 1 and 2, as shown in Figure 4-2.
2. With the power off, install the Model 7016A card in the
mainframe.
3. Turn on the mainframe and the Model 6517A power,
and allow the electrometer to warm up for at least one
hour before making measurements. Make sure the voltage source is turned off.
4. Select the Model 6517A ohms function, choose the
200M Ω range, and make certain zero check is disabled.
5. Close channel 1 on the Model 7016A.
4-3
Service Information
WARNING:NO INTERNAL OPERATOR SERVICABLE PARTS,SERVICE BY QUALIFIED PERSONNEL ONLY.
WARNING:NO INTERNAL OPERATOR SERVICABLE PARTS,SERVICE BY QUALIFIED PERSONNEL ONLY.
CAUTION:FOR CONTINUED PROTECTION AGAINST FIRE HAZARD,REPLACE FUSE WITH SAME TYPE AND RATING.
CAUTION:FOR CONTINUED PROTECTION AGAINST FIRE HAZARD,REPLACE FUSE WITH SAME TYPE AND RATING.
6. Program the Model 6517A voltage source for 30V, and
make sure the internal voltage source connection mode
is selected.
7. Turn on the Model 6517A voltage source, and allow the
reading to settle.
8. Verify that the Model 6517A resistance reading is
>100M Ω .
9. Turn off the voltage source, and open channel 1.
A
A
A
A
B
Ch. 1
Ch. 2
Out A
Ch. 3
Ch. 4
A
Ch. 5
10. Repeat the procedure for channels 2 through 4, measuring the resistance between the center conductor of each
channel and the center conductors of all other channels
of multiplexer A. For each test:
• Connect the electrometer to the center conductors of
the two channels being tested.
• Close only one of the channels being tested.
11. Repeat the entire procedure to test channel isolation between all multiplexer B channels (channels 5-8).
SMA-to-BNC to triax adapter
Triax Cable
Connect voltage source low
to card signal low
Voltage Source High
1010V
PEAK
Input
V SOURCE
EXT TRIGINMTR COMP
OUT
RS232
!
INTERLOCK
DIGITAL
I/O
HI
SELECTED
LINE VOLTAGE
90-110V
105-125V
TRIG LINK
180-220V
210-250V
115V
LINE RATING
50-60HZ
50VA MAX
AC ONLY
(CHANGE IEEE ADDRESS
WITH FRONT PANEL MENU)
PREAMP OUT
!
250V PEAK
COMMON 2V ANALOG
250 PEAK
INPUT
TEMP
TYPE K
OPTION SLOT
OUTPUT
HUMIDITY
LO
750V
PEAK
Model 6517A Electrometer
Note: Configure electrometer for
internal voltage source
connection.
IEEE-488
LINE FUSE
SLOWBLOW
1/2A 90-125V
1/4A 180-250V
MADE
IN
U.S.A.
Model 7016A
Figure 4-2
Connections for channel isolation tests
4-4
Ch. 6
B
Out B
B
Ch. 7
Ch. 8
B
B
A
A
Ch. 1
Ch. 2
A
A
Ch. 3
Ch. 4
A
Out A
B
B
Ch. 5
Ch. 6
B
B
Ch. 7
Ch. 8
B
Out B
Input
Voltage Source High
Triax Cable
WARNING:NO INTERNAL OPERATOR SERVICABLE PARTS,SERVICE BY QUALIFIED PERSONNEL ONLY.
WARNING:NO INTERNAL OPERATOR SERVICABLE PARTS,SERVICE BY QUALIFIED PERSONNEL ONLY.
CAUTION:FOR CONTINUED PROTECTION AGAINST FIRE HAZARD,REPLACE FUSE WITH SAME TYPE AND RATING.
CAUTION:FOR CONTINUED PROTECTION AGAINST FIRE HAZARD,REPLACE FUSE WITH SAME TYPE AND RATING.
INPUT
250V PEAK
!
LINE RATING
50-60HZ
50VA MAX
AC ONLY
LINE FUSE
SLOWBLOW
1/2A 90-125V
1/4A 180-250V
IEEE-488
(CHANGE IEEE ADDRESS
WITH FRONT PANEL MENU)
DIGITAL
I/O
TRIG LINK
115V
LO
HI
RS232
!
MADE
IN
U.S.A.
PREAMP OUT
250 PEAK
COMMON 2V ANALOG
OUTPUT
TEMP
TYPE K
HUMIDITY
OPTION SLOT
V SOURCE
EXT TRIGINMTR COMP
OUT
INTERLOCK
SELECTED
LINE VOLTAGE
90-110V
105-125V
180-220V
210-250V
1010V
PEAK
750V
PEAK
Model 6517A Electrometer
Note: Configure electrometer for
internal voltage source
connection.
Model 7016A
Adapter (see Figure 4-2)
Figure 4-3
Connections for center-to-shield isolation tests
Service Information
Center-to-shield isolation
Perform the following steps to check center-to-shield isolation:
1. Connect the Model 6517A Electrometer to the center conductor and shield of channel 1, as shown in Figure 4-3.
2. With the power off, install the Model 7016A card in the
mainframe.
3. Turn on the mainframe and the Model 6517A power,
and allow the electrometer to warm up for at least one
hour before making measurements. Make sure the voltage source is turned off.
4. Select the Model 6517A ohms function, choose the
2G Ω range, and make certain zero check is disabled.
5. Close channel 1 on the Model 7016A.
6. Program the Model 6517A voltage source for 30V, and
make sure the internal voltage source connection mode
is selected.
7. Turn on the Model 6517A voltage source, and allow the
reading to settle.
8. Verify that the Model 6517A resistance reading is
>1G Ω .
9. Turn off the voltage source, and open channel 1.
10. Repeat the procedure for channels 2 through 8, measuring the resistance between the center conductor and
shield of each channel. For each test:
• Connect the electrometer to the center conductor and
shield of the channel being tested.
• Close only the channel being tested.
4-5
Service Information
WARNING:NO INTERNAL OPERATOR SERVICABLE PARTS,SERVICE BY QUALIFIED PERSONNEL ONLY.
WARNING:NO INTERNAL OPERATOR SERVICABLE PARTS,SERVICE BY QUALIFIED PERSONNEL ONLY.
CAUTION:FOR CONTINUED PROTECTION AGAINST FIRE HAZARD,REPLACE FUSE WITH SAME TYPE AND RATING.
CAUTION:FOR CONTINUED PROTECTION AGAINST FIRE HAZARD,REPLACE FUSE WITH SAME TYPE AND RATING.
Multiplexer-to-multiplexer isolation
Perform the following steps to check multiplexer-to-multiplexer isolation:
1. Connect the Model 6517A Electrometer to the center
conductors of channels 1 and 5, as shown in Figure 4-4.
2. With the power off, install the Model 7016A card in the
mainframe.
3. Turn on the mainframe and the Model 6517A power,
and allow the electrometer to warm up for at least one
hour before making measurements. Make sure the voltage source is turned off.
A
A
A
A
B
Ch. 1
Ch. 2
Out A
Ch. 3
Ch. 4
A
Ch. 5
4. Select the Model 6517A ohms function, choose the
2G Ω range, and make certain zero check is disabled.
5. Close channels 1 and 5 on the Model 7016A.
6. Program the Model 6517A voltage source for 30V, and
make sure the internal voltage source connection mode
is selected.
7. Turn on the Model 6517A voltage source, and allow the
reading to settle.
8. Verify that the Model 6517A resistance reading is
>1G Ω .
9. Turn off the voltage source, and open channels 1 and 5.
Adapter (see Figure 4-2)
Triax Cable
Voltage Source High
1010V
PEAK
Input
PREAMP OUT
TYPE K
COMMON 2V ANALOG
250 PEAK
TEMP
OPTION SLOT
!
INPUT
250V PEAK
OUTPUT
HUMIDITY
LO
750V
PEAK
Model 6517A Electrometer
HI
SELECTED
LINE VOLTAGE
90-110V
V SOURCE
EXT TRIGINMTR COMP
RS232
180-220V
105-125V
210-250V
LINE RATING
50-60HZ
115V
50VA MAX
DIGITAL
AC ONLY
IEEE-488
(CHANGE IEEE ADDRESS
WITH FRONT PANEL MENU)
TRIG LINK
I/O
OUT
!
INTERLOCK
Note: Configure electrometer for
internal voltage source
connection.
LINE FUSE
SLOWBLOW
1/2A 90-125V
1/4A 180-250V
MADE
IN
U.S.A.
B
B
B
B
Model 7016A
Figure 4-4
Connections for multiplexer-to-multiplexer isolation tests
4-6
Ch. 6
Out B
Ch. 7
Ch. 8
Figure 4-5
Block diagram
Service Information
4.3.5Special handling of static-sensitive devices
CMOS and other high-impedance devices are subject to possible static discharge damage because of the high-impedance
levels involved. When handling such devices, observe the
precautions listed below.
NOTE
To prevent damage, assume that all parts
are static-sensitive.
1. Such devices should be transported and handled only in
containers specially designed to prevent or dissipate
static build-up. Typically, these devices will be received
in anti-static containers made of plastic or foam. Keep
these parts in their original containers until ready for installation or use.
2. Remove the devices from their protective containers
only at a properly grounded workstation. Also, ground
yourself with an appropriate wrist strap while working
with these devices.
3. Handle the devices only by the body; do not touch the
pins or terminals.
4. Any printed circuit board into which the device is to be
inserted must first be grounded to the bench or table.
5. Use only anti-static type de-soldering tools and grounded-tip soldering irons.
4.4Principles of operation
The following paragraphs discuss the basic Model 7016A
operating principles that can be used as an aid in troubleshooting the card. The schematic diagram of the card is located at the end of Section 5.
4.4.1Block diagram
Figure 4-5 shows a simplified block diagram of the Model
7016A. Key sections include the relay data control circuits,
the relay driver IC, the relays, and the card configuration
memory. These v arious elements are discussed in the following paragraphs.
From
Mainframe
To
Mainframe
Power Up/Down
Data
Clock
Strobe
Safeguard
Memory
U101
Relay
Driver
U102
+6V
Out A
MUX
A
K101-K107
Out B
MUX
B
K108-K114
1
2
Multiplexer A
3
4
5
6
Multiplexer B
Inputs
7
8
Inputs
4-7
Service Information
4.4.2Relay control
Card relays are controlled by serial data transmitted from the
host switching mainframe via the DATA line. Each control
byte is shifted in serial fashion into latches located in the card
relay driver IC (U102). The serial data is clocked in by the
CLK (clock) line.
Once the relay control byte has been shifted into the card, the
STR line is set high to latch the relay information into the Q
outputs of the relay drivers, and the appropriate relays are energized (assuming the driver outputs are enabled, as discussed below). Note that a relay driver output goes low to
energize the corresponding relay.
The output enable (OE) line of U102 is controlled by the
power-up/power-down safeguard circuit located in the mainframe. This circuit assures that no card relays are inadvertently energized when the mainframe power is turned on or of f.
4.4.3Switching circuits
Signal switching is performed by relays K101 through K114.
K104-K104 switch channels 1 through 4, while K108-K111
switch channels 5 through 8. K105-K107 provide additional
switching to assure proper isolation for multiplexer 1, while
K112-K114 provide a similar function for multiplexer 2.
4.4.4Card configuration memory
Card configuration information is stored in U101. This information is serially read by the mainframe during power-up
and allows the unit to determine the card model number and
card relay configuration information.
4.5Troubleshooting
4.5.1Troubleshooting equipment
Table 4-3 summarizes recommended equipment for troubleshooting the Model 7016A.
Table 4-3
Recommended troubleshooting equipment
Manufacturer
Description
Multimeter
Oscilloscope
4.5.2Troubleshooting procedure
T able 4-4 summarizes multiplexer card troubleshooting steps.
Refer to the schematic diagram and component layout drawing at the end of Section 5 for component locations.
Use care when removing relays from the
PC board to avoid pulling traces away
from the circuit board. Before attempting to remove a relay, use an appropriate de-soldering tool to clear each
mounting hole completely free of solder.
Each relay pin must be free to move in
its mounting hole before removal. Also,
make certain that no burrs are present
on the ends of the relay pins.
and ModelApplication
Keithley
TEK 2243
CAUTION
DCV checks
View logic waveforms
Table 4-4
Troubleshooting procedure
StepItem/componentRequired conditionComments
1
Digital ground
P2001, pins 15 and 16
2
P2001, pin 1
3
P2001, pin 14
4
U102, pin 2
5
U102, pin 3
6
U102, pin 7
7
U102, pins 11-18
4-8
+6VDC
+5VDC
CLK pulses
DATA pulses
STR pulse
Low with relay energized, high
with relay de-energized.
All voltages referenced to digital ground.
Card 6V relay supply voltage.
Card 5V logic supply voltage.
During relay update sequence only.
During relay update sequence only.
End of relay update sequence.
Relay driver outputs.
5
Replaceable Parts
5.1Introduction
This section contains replacement parts information, schematic diagrams, and component layout drawings for the
Model 7016A.
5.2Parts list
The parts list for the multiplexer card is included in tables integrated with the schematic diagram and component layout
drawing. Parts are listed alphabetically in order of circuit
designation.
5.3Ordering information
To place an order, or to obtain information concerning replacement parts, contact your Keithley representative or the
factory (see the inside front cover for addresses). When ordering parts, be sure to include the following information:
• Card model number (7016A)
• Card serial number
• Part description
• Circuit description, if applicable
• Keithley part number
5.4Factory service
If the card is to be returned to Keithley Instruments for repair ,
perform the following:
• Call the Repair Department at 1-800-552-1115 for a
Return Material Authorization (RMA) number.
• Complete the service form at the back of this manual
and include it with the card.
• Carefully pack the card in the original packing carton.
• Write ATTENTION REPAIR DEPT and the RMA
number on the shipping label.
NOTE
It is not necessary to return the switching
mainframe with the card.
5.5Component layout and schematic diagram
A component layout drawing and schematic diagram are included on the following pages integrated with the parts list.