Isolated, digital input and output (i/o) boards (76 pages)
Summary of Contents for Keithley 7021
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Instruction Manual Model 7021 Multiplexer-Digital I/O Card Contains Operating and Servicing Information Artisan Scientific - Quality Instrumentation ... Guaranteed | (888) 88-SOURCE | www.artisan-scientific.com...
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WARRANTY 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.
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Revision of the manual. Each new Revision includes a revised copy of this print history page. Revision A (Document Number 7021-901-01)..................May 1997 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.
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(IEC) Standard IEC 664, digital multimeter measuring circuits The types of product users are: (e.g., Keithley Models 175A, 199, 2000, 2001, 2002, and 2010) measuring circuits are Installation Category II. All other instru- Responsible body is the individual or group responsible for the use ments’...
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fire hazard. leads, and input jacks, must be purchased from Keithley Instru- ments. Standard fuses, with applicable national safety approvals, Chassis connections must only be used as shield connections for may be used if the rating and type are the same.
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7021 S ODEL PECIFICATIONS ANALOG MULTIPLEXER SPECIFICATIONS DIGITAL I/O SPECIFICATIONS MULTPLEXER CONFIGURATION: Independent 1 × 12 and 1 × 18 DIGITAL I/O CAPABILITY: 10 independent inputs. multiplex banks. Adjacent banks can be connected together. 10 independent outputs. Jumpers can be removed to isolate any bank from the backplane.
Table of Contents General Information Introduction ................................1-1 Features ................................1-1 Warranty information............................1-2 Manual addenda ..............................1-2 Safety symbols and terms ........................... 1-2 Specifications ..............................1-2 Unpacking and inspection ........................... 1-2 Inspection for damage ..........................1-2 Handling precautions ........................... 1-2 Shipping contents ............................
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Two-card system ............................4-11 Two-mainframe system ..........................4-12 Typical digital I/O connection schemes ......................4-14 Output connection schemes........................4-14 Input connection scheme ........................... 4-15 Model 7021 installation and removal ........................ 4-16 Card installation............................4-16 Card removal ..............................4-16 Operation Introduction ................................. 5-1 Power limits.................................
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Measurement considerations..........................5-13 Path isolation............................. 5-13 Magnetic fields............................5-14 Radio frequency interference ........................5-14 Ground loops............................. 5-14 Keeping connectors clean ......................... 5-15 AC frequency response ..........................5-15 Service Information Introduction ................................. 6-1 Handling and cleaning precautions ........................6-1 Performance verification............................. 6-2 Environmental conditions ...........................
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List of Illustrations Matrix Configuration Figure 2-1 Model 7021 simplified schematic ....................... 2-1 Dual 1 × 12 and 1 × 18 multiplexer configuration (jumpers not installed)..........2-2 Figure 2-2 One 1 × 30 multiplexer configuration (jumpers installed)................2-2 Figure 2-3 Figure 2-4 Model 7001/7002 analog backplane ......................
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Configuration for current gain and common-emitter test................5-11 Figure 5-9 Typical common-emitter characteristics ....................5-12 Figure 5-10 Connecting model 7021 and model 7022 cards together ................5-12 Figure 5-11 Path isolation resistance ..........................5-13 Figure 5-12 Voltage attenuation by path isolation resistance ..................5-13 Figure 5-13 Power line ground loops..........................
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Table 7-1 Relay card for Model 7021 parts list......................7-2 Table 7-2 Mass terminated connector card for Model 7021 parts list................7-4 Table 7-3 Model 7011-KIT-R 96-pin female DIN connector kit parts list ..............7-4 Artisan Scientific - Quality Instrumentation ... Guaranteed | (888) 88-SOURCE | www.artisan-scientific.com...
General Information Introduction Features The Model 7021 has two-pole, independent 1 × 12 and 1 × 18 This section contains general information about the Model 7021 multiplexer-digital I/O card. multiplex banks and ten independent inputs and outputs for both multiplexer and digital I/O capabilities. Some of the key...
Warranty information Specifications Warranty information is located on the inside front cover of Model 7021 specifications are found at the front of this man- this instruction manual. Should your Model 7021 require ual. These specifications are exclusive of the mainframe warranty service, contact the Keithley representative or au- specifications.
7021 and to a standard 96-pin male DIN bulkhead connector (see Model 7011-MTR). Repacking for shipment Should it become necessary to return the Model 7021 for re- pair, carefully pack the unit in its original packing carton, or the equivalent, and include the following information: •...
Introduction Basic multiplexer configurations This section covers the basics for multiplexer switching and A simplified schematic of the Model 7021 multiplex banks is is arranged as follows: shown in Figure 2-1. It is organized as two multiplex banks: 1 × 12 and 1 × 18. Bank A has 12 inputs and one output, and •...
Figure 2-4. The GUARD connection stalled (Figure 2-2). of the analog backplane is found only on the mainframe and is not used with the Model 7021 or Model 7022 card. One 1 × 30 multiplex bank; all bank-to-bank jumpers in- •...
Multiplexer Configuration Figure 2-5 shows how each bank of the Model 7021 is con- NOTE nected to the backplane. Notice that since the Model 7021 is The Model 7001/7002 does not provide an a two-pole card, there is no connection made to the GUARD analog backplane for the non-701X/702X/ terminal of the backplane.
Whenever path resistance is a consideration, sensing should be used. Bank A Bank B Source or 7021 Measure Figure 2-7 Differential switching example Bank A Source HI...
Multiplexer Configuration SMU connections Multiple-card switching systems Figure 2-9 shows how to connect a Keithley Model 236, 237, The Model 7001/7002 switch system mainframes can ac- or 238 Source Measure Unit to the multiplexer. By using tri- commodate two and ten cards, respectively. The following...
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Figure 2-10 shows an exam- multiplex banks of the card installed in slot 1 (CARD 1) are ple using two Model 7021 cards. automatically connected to the multiplex banks of the card installed in slot 2 (CARD 2) through the analog backplane.
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Figure 2-11 shows an example of input expansion. Each Figure 2-12 shows a possible switching system using a ma- Model 7021 card is configured with dual 1 × 12 and 1 × 18 trix and a multiplexer. The backplane jumpers for both the multiplex banks.
Rows Bank B 5x6 Matrix Dual 1x12 and 1x18 Mux Notes: 1. Models 7021 and 7022 backplane jumpers must be removed from rows 2 and 4. 2. Model 7021 bank-to-bank jumpers must be removed. Figure 2-12 Mixed card type example...
(open). Refer to Section 4 to configure the logic to your requirement. This section covers the basic digital input and output config- urations for the Model 7021. Connection information for these configurations is provided in Section 4 of this manual, Controlling pull-up devices while operation (front panel and IEEE-488 bus) is explained in Section 5.
If you need a higher logic level, you may result in damage to the output can place the jumper in the alternate position and apply an drivers. external voltage (via V 7021 Jumper 10kΩ gate Logic...
When the resistor is connected to 5V, the channel is pulled high. Thus, with nothing connected to the channel, the input is pulled high to 5V which displays the channel as on. 7021 = Pull-up resistor 10kΩ = Input protection resistor 10kΩ...
• Model 7021 installation and removal — Provides the nel. Do not perform these procedures procedures to install and remove the Model 7021 card unless qualified to do so. Failure to rec- from the Model 7001/7002 mainframe. ognize and observe normal safety pre- cautions could result in personal injury or death.
The Model 7001/7002 mainframe has an analog backplane lowing steps to install the backplane row jumpers: that allows the multiplex banks of a Model 7021 to be inter- nally connected to a compatible switching card installed in 1. If mated together, separate the relay card from the con- the adjacent slot (See Section 2 for details).
Card Connections and Installation J205 J204 J201 Figure 4-2 Bank-to-bank jumper locations Digital I/O connections Bank-to-bank jumpers As explained in Section 2, the multiplex banks can be con- Voltage source jumper nected together (using plug-in jumpers) to form large multi- Digital output uses the internal +5V source as the high logic plexers.
Card Connections and Installation The voltage source jumper is located on the connector board as shown in Figure 4-2. Figure 4-5 shows how the plug-in jumper is installed on J201. Jumper Jumper V EXT V EXT A. External Source Selected B.
Figure 4-9 and Table 4-2. This connector will mate to a 96-pin female DIN con- nector. Down Pins of the Model 7021 mass termination connector can be identified in one of three ways: B. Pull-up Resistance Selected •...
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Card Connections and Installation Table 4-2 Pin designation identification Conn. Schem. Conn. Schem. Conn. Schem. desig. desig. desig. desig. desig. desig. terminal 1a-32c 1-96 terminal 1a-32c 1-96 terminal 1a-32c 1-96 Bank A Chan 1, HI Bank A Chan 16, HI OUT A, HI Chan 1, LO Chan 16, LO...
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(plugged in) after the Model that you wish to connect to the card must be terminated with 7021 is installed in the Model 7001/7002 a single 96-pin female DIN connector. The following con- mainframe and with the mainframe power nection techniques provide some guidelines and suggestions off.
Card Connections and Installation View from solder cup side of connector Note: See Figure 4-9 for terminal identification. Figure 4-11 Model 7011-MTR connector pinout In Figure 4-10A, connections are accomplished using a Model 7011-MTC-2 cable and a Model 7011-MTR bulk- head connector.
7011-MTC-2 round cable assembly. This cable mates direct- multiplex banks. ly to both the external bulkhead connector and the Model 7021. Notice that the bulkhead connector is shown mounted to a fixture to help keep the cabling stable during the test. 7021...
When using a single-card system, make sure that the card re- mains electrically isolated from any other switching cards. Figure 4-14 shows a system using two Model 7021 cards in- There are several ways to ensure isolation for a single card in stalled in one Model 7001/7002 mainframe to configure a...
The unterminated ends of the two cables are hard-wired to instrumentation and DUT as shown in the drawing. The other ends of these cables mate directly to the Model 7021 cards. Two-mainframe system Figure 4-15 shows a system using three multiplexer cards in- stalled in two Model 7001/7002 mainframes to configure a...
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P/N N2807-P/D-50TAB. This cable contains 50 con- ductors; two lengths provide 100 conductors. This cable will mate to the Model 7021. The unterminated end of the cable is connected directly to the instrumentation and DUT. Notice that the bank connections for the third card are made at the instruments.
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Card Connections and Installation DUT Test Fixture 7011-Kit-R Connector Kit 7001/7002 #2 Cable Trigger Link 7021 Not Used Trigger Link Cable Instrument 7001/7002 #1 Trigger Link 7021 7011-MTC-2 Cable Assembly 7021 (Cut in half to provide two cables) DUT Test Fixture...
12V source is used to provide the necessary voltage level. A motor is turned on when the corresponding output channel is Typical digital I/O connection schemes turned on (closed). 7021 Motors Output connection schemes The following examples show output connections from the card to external circuitry and summarize the required inter- –...
Card Connections and Installation Logic Device 7021 OUT 31 74LS138 DMUX OUT 32 OUT 33 V CC Internal connections: Internal voltage source (+5V) used. Figure 4-18 Digital output, logic device control Micro- 7021 switches Input connection scheme IN 1 IN 2 Figure 4-19 shows a digital input connection scheme to mon- itor the state of micro-switches.
7021 card in. Installation or removal of the Model 3. Referring to Figure 4-20, feed the Model 7021 card into 7021 is to be performed by qualified ser- the desired slot so the edges of the relay card ride in the vice personnel.
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Card Connections and Installation ber to handle the card by the edges and shields to avoid contamination that could degrade performance. 4-18 Artisan Scientific - Quality Instrumentation ... Guaranteed | (888) 88-SOURCE | www.artisan-scientific.com...
Model 7021 to make measurements. Mainframe control of the card Power limits The following information pertains to the Model 7021. It assumes that you are familiar with the operation of the CAUTION Model 7001/7002 mainframe—whichever is used.
Operation 7001 Display CARD 1 CARD 2 = Open Channel = Closed Channel Figure 5-1 Model 7001 channel status display Channel assignments The hardware for the digital output channels is user config- urable for negative or positive true logic. That is, depending The Model 7001 has a channel status display (Figure 5-1) on the user configuration, the output can go high or be that provides the real-time state of each available channel.
Operation Closing and opening channels Scanning channels NOTE Channels are scanned by creating a scan list and configuring the Model 7001/7002 to perform a scan. The scan list is cre- This procedure applies to multiplexer ated in the same manner as a channel list (See the Closing channels (channels 1!1 through 1!30) and and opening channels paragraph).
Bus operation is demonstrated using Microsoft QuickBASIC The first statement selects the *RST default configuration for 4.5, the Keithley KPC-488.2 (or Capital Equipment Corpo- the scan. The second statement sets channel count to the ration) IEEE interface and the HP-style Universal Language scan-list-length (5).
Model 7021. These include resistor testing and transistor or :SENSe7:DATA? (@2) :SENSe7:DATA? (@6!2) testing. It also shows how to use the Model 7021 with a ma- trix-digital I/O card (Model 7022). After the mainframe is addressed to talk, the response mes- sage will indicate the state of each listed input channel.
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Model 2000 DMM. Since only two-pole switch- multiplexer inputs, close the shorted channel, and then ing is required for this application, one Model 7021 card can enable the DMM zero feature to cancel path resistance. be used to switch up to 30 resistors (additional multiplex Leave zero enabled for the entire test.
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Model 2000 DMM are routed through the cause two channels must close at the same time. multiplexer to the resistor under test. The extra set of sense 7021 Input HI Sense Ω 4 Wire...
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Bank A, In 6 and detrimental effect on measurement accuracy unless steps are Bank B, In 5 taken to avoid them. (The Model 7021 has been designed to 7 and 8 Bank A, In 7 and keep relay EMF at a minimal level.) Thermal EMF effects...
Typical transistor tests that can be performed with the aid of is used to source the base current, I . The Model 230 Volt- the Model 7021 include current gain tests, leakage tests, as age Source supplies the collector-emitter voltage, V , and...
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Operation 7021 Measure Amps POWER Model 2000 Output Common Source Model 230 Voltage Source DUT (12) Output Dual 1x12 MUX Source Note: Bank B channels 13 through 18 are not used. Model 224 Current Source A. Test Configuration 2000 230 Voltage...
Testing with matrix-digital I/O cards (Figure 5-9). The Model 7021 can be added to a matrix switching system to enhance the test capabilities of that system. The follow- ing paragraphs discuss an overall multiplexer/matrix switching system and also briefly outline a typical test that...
Instrument Card Measurement considerations = Source Resistance of DUT Many measurements made with the Model 7021 are subject = Source EMF of DUT to various effects that can seriously affect low-level measure- = Path Isolation Resistance ment accuracy. The following paragraphs discuss these ef- PATH fects and ways to minimize them.
Operation Magnetic fields Many instruments incorporate internal filtering that may help to reduce RFI effects in some situations. In some cases, When a conductor cuts through magnetic lines of force, a additional external filtering may also be required. Keep in very small current is generated.
As is the case with any high-resistance device, the integrity of connectors can be damaged if they are not handled prop- The AC frequency response of the Model 7021 is important erly. If connector insulation becomes contaminated, the in test systems that switch AC signals. Refer to the specifi- insulation resistance will be substantially reduced, affecting cations at the front of this manual.
Do not attempt to perform these procedures Because of the high impedance areas on the Model 7021, unless you are qualified to do so. care should be taken when handling or servicing the card to prevent possible contamination, which could degrade perfor- mance.
96-pin female DIN connector and then mating faces or components. On plugs and it to the connector on the Model 7021. Input and output receptacles, do not touch areas adjacent shorting connections can also be done at the connector. The to the electrical contacts.
7. Connect INPUT LO and INPUT Ω 4 WIRE LO to the CAUTION HI (H) terminal of bank A. After making solder connections to a 8. Install the Model 7021 in slot 1 (CARD 1) of the Model connector, remove solder flux as ex- 7001/7002. plained in the Handling and cleaning 9.
15. Repeat steps 7 through 12 to check that the common- in Figure 6-2A. mode offset current is <100pA. 5. Install the Model 7021 in slot 1 (CARD 1) of the main- frame. 6. Turn on the Model 7001/7002. Artisan Scientific - Quality Instrumentation ... Guaranteed | (888) 88-SOURCE | www.artisan-scientific.com...
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FOR CONTINUED PROTECTION AGAINST FIRE HAZARD,REPLACE FUSE WITH SAME TYPE AND RATING. FOR CONTINUED PROTECTION AGAINST FIRE HAZARD,REPLACE FUSE WITH SAME TYPE AND RATING. Bank Inputs (Red) Bank (Blk) Outputs Model 7021 A) Differential Model 7025 Unterminated Triax Cable Model 6517A (Measure Current)
Service Information Contact potential tests 7. Install the Model 7021 in the Model 7001/7002 slot 1, and turn on the mainframe. These tests check the EMF generated by each relay contact 8. Allow Models 7001/7002, 7021, and 182 to warm up for pair (H and L) for each pathway.
Service Information Bank and channel-to-channel isolation tests 4. Install the Model 7021 in slot 1 (CARD 1) and turn on the mainframe. Bank isolation tests check the leakage resistance between ad- jacent banks. Channel-to-channel isolation tests check the leakage resistance between a bank output connection and a...
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A inputs. Remember to move bank input connections as indicated in the table. 12. Install the Model 7021 in slot 1 and turn on the main- frame. 18. Use Table 6-3 (test numbers 12 through 28) and the above procedure to test bank B inputs.
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Bank A, Input 27 to Bank B, Input 23 Bank A and Bank B 1!27 and 1!23 *Assumes Model 7021 is installed in slot 1 of mainframe. Programmed as slot (1) and channel. Artisan Scientific - Quality Instrumentation ... Guaranteed | (888) 88-SOURCE | www.artisan-scientific.com...
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Bank B, Input 29 to Bank B, Input 30 Bank B and Input 29 1!30 *Assumes Model 7021 is installed in slot 1 of mainframe. Programmed as slot (1) and channel. 6-10 Artisan Scientific - Quality Instrumentation ... Guaranteed | (888) 88-SOURCE | www.artisan-scientific.com...
(100V) 6-6. across the terminals and then measuring the leakage current. 6. Install the Model 7021 in slot 1 (CARD 1), and turn on The isolation resistance is then calculated as R = V/I. In the the mainframe.
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17. Turn off the mainframe, and connect the electrometer to 16. Turn off the Model 6517A voltage source. the Model 7021 as shown in Figure 6-7. 18. Repeat steps 3 through 15 to check common-mode iso- lation. Verify that each reading is >1G Ω (10 Ω...
Bank B, Input 30 1!30 parts are static-sensitive. *Assumes Model 7021 is installed in slot 1 of mainframe. Pro- grammed as slot (1) and channel. 1. Such devices should be transported and handled only in containers specially designed to prevent or dissipate static buildup.
The following paragraphs discuss the basic operating princi- ples for the Model 7021 and can be used as an aid in trouble- shooting the card. Schematic drawings 7021-106 and 7021- 172 are located in Section 7.
Service Information ID data circuits 4. Once all data is received, the mainframe sends a stop command, which is a low-to-high transition of the ID- Upon power-up, card identification information from each DATA line with the IDCLK line held high (Figure 6-10). card is read by the mainframe.
Service Information Multiplexer relay power control Power-on safeguard A relay power control circuit, made up of U114, U115, NOTE Q100, Q101, and associated components, keeps power dissi- The power-on safeguard circuit discussed pated in relay coils at a minimum, thus reducing possible below is actually located on the digital problems caused by thermal EMFs.
Service Information Troubleshooting Troubleshooting equipment Table 6-5 summarizes recommended equipment for trouble- WARNING shooting the Model 7021. Lethal voltages are present within the Model 7001/7002 mainframe. Some of Table 6-5 the procedures may expose you to haz- Recommended troubleshooting equipment ardous voltages.
Replaceable Parts Introduction Factory service This section contains replacement parts information, sche- If the card is to be returned to Keithley Instruments for repair, matic diagrams, and component layout drawings for the perform the following: Model 7021. 1. Complete the service form at the back of this manual and include it with the card.
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Replaceable Parts NOTE Table 7-2 — Parts List, Mass Terminated Connector Card for 7021. The Model 7021 and 7022 use the same 7021-170 — Component Layout, Mass Terminated Connec- relay card; only the connector cards are tor Card for 7021.
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Replaceable Parts Table 7-1 (continued) Relay card for Model 7021 parts list Circuit Keithley designation Description part no. R136 RES, 2.49K, 1%, 1/8W, METAL FILM R-88-2.49K R137 RES, 1.15K, 1%, 1/8W, METAL FILM R-88-1.15K R138 RES, 1K, 1%, 1/8W, METAL FILM...
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Replaceable Parts Table 7-2 Mass terminated connector card for Model 7021 parts list Circuit Keithley designation Description part no. 2-56X3/16 PHILLIPS PAN HEAD SCREW (FOR SHIELD) 2-56X3/16PPH 2-56X3/8 PHILLIPS PAN HEAD SCREW (FOR BRACKET) 2-56X3/8PPH 2-56X7/16 PHILLIPS PAN HEAD SCREW...
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APPR. C O N N E C T O R B O A R D C A B DIM. TOL. UNLESS OTHERWISE SPECIFIED KEITHLEY INSTRUMENTS INC. XX=+.01 ANG.=+1 DO NOT SCALE THIS DRAWING 7 0 2 1 - 1 7 0 CLEVELAND, OHIO 44139 XXX=+.005...
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RELEASED 9.570 +.003 -.003 9.420 (8.720) (6.363) (5.960) NOTES: 1. MUST COMPLY TO KEITHLEY SPECIFICATION #QS-354. (2.463) 2. BOARD MUST BE FABRICATED USING UL APPROVED MATERIAL AND PROCESSES. .040 3. SUBSTRATE: NEMA GRADE FR4 BASE COPPER (OZ.): 1 OZ. .150 2 OZ.
Index Configuring digital I/O output logic 4-4 AC frequency response 5-15 Ground loops 5-14 Contact potential tests 6-6 Analog multiplexer maximum signal Controlling devices using pull-up levels 5-1 resistors 3-2 Controlling pull-up devices 3-1 Current gain tests 5-10 Handling and cleaning precautions 6-1 Backplane jumpers 2-2 Handling precautions 1-2, 4-1...
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Measurement considerations 5-13 Power limits 5-1 Troubleshooting access 6-17 Mixing card types 2-7 Principles of operation 6-14 Troubleshooting equipment 6-17 Model 7021 installation and Pull-up resistors 4-4 Troubleshooting procedure 6-18 removal 4-16 Turning channels on and off 5-5 Multi-pin (mass termination)
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Service Form Model No. Serial No. Date Name and Telephone No. Company List all control settings, describe problem and check boxes that apply to problem. Intermittent Analog output follows display Particular range or function bad; specify IEEE failure Obvious problem on power-up Batteries and fuses are OK Front panel operational All ranges or functions are bad...
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Keithley Instruments, Inc. 28775 Aurora Road Cleveland, Ohio 44139 Printed in the U.S.A. Artisan Scientific - Quality Instrumentation ... Guaranteed | (888) 88-SOURCE | www.artisan-scientific.com...
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