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UM.book Page 2 Tuesday, July 14, 1998 10:37 AM Internet Support E-mail: support@natinst.com FTP Site: ftp.natinst.com Web Address: http://www.natinst.
UM.book Page 3 Tuesday, July 14, 1998 10:37 AM Important Information Warranty The BNC-2140 is warranted against defects in materials and workmanship for a period of one year from the date of shipment, as evidenced by receipts or other documentation. National Instruments will, at its option, repair or replace equipment that proves to be defective during the warranty period. This warranty includes parts and labor.
UM.book Page v Tuesday, July 14, 1998 10:37 AM Contents About This Manual Organization of This Manual .........................................................................................vii Conventions Used in This Manual.................................................................................viii Related Documentation..................................................................................................viii Customer Communication ....................................................
UM.book Page vi Tuesday, July 14, 1998 10:37 AM Contents Power Requirement (from DSA board) .......................................................... A-2 Physical ........................................................................................................... A-2 Environment.................................................................................................... A-2 Appendix B Customer Communication Glossary Index Figures Figure 2-1. Switch Settings and Signal Connections.........
UM.book Page vii Tuesday, July 14, 1998 10:37 AM About This Manual This manual describes the electrical and mechanical aspects of the BNC-2140 accessory and contains information concerning its operation. Organization of This Manual The BNC-2140 User Manual is organized as follows: • Chapter 1, Introduction, describes the BNC-2140 accessory, lists what you need to get started, explains how to unpack your BNC-2140, and describes optional equipment.
UM.book Page viii Tuesday, July 14, 1998 10:37 AM About This Manual Conventions Used in This Manual The following conventions are used in this manual: <> Angle brackets containing numbers separated by an ellipsis represent a range of values associated with a bit or signal name—for example, DIO<3..0>. This icon to the left of bold italicized text denotes a note, which alerts you to important information.
UM.book Page 1 Tuesday, July 14, 1998 10:37 AM 1 Introduction This chapter describes the BNC-2140 accessory, lists what you need to get started, explains how to unpack your BNC-2140, and describes optional equipment. Thank you for buying the BNC-2140 accessory for DSA.The BNC-2140 is a signal conditioning accessory specifically designed for use with a dynamic signal acquisition (DSA) series device.
UM.book Page 2 Tuesday, July 14, 1998 10:37 AM Chapter 1 Introduction What You Need to Get Started To set up and use your BNC-2140 device, you will need the following: ❑ BNC-2140 ❑ One of the following DSA devices: PCI-4451 PCI-4452 NI 4551 NI 4552 ❑ BNC-2140 User Manual ❑ Your computer ❑ SHC68-C68-A1 analog cable Unpacking Your BNC-2140 is shipped in an antistatic plastic package to prevent electrostatic damage to the device. Several components on the device can be damaged by electrostatic discharge.
UM.book Page 3 Tuesday, July 14, 1998 10:37 AM Chapter 1 Introduction If your application requires that you use a prepolarized microphone with a microphone preamplifier, contact Brüel and Kjær. Custom Cabling National Instruments offers cables of different lengths for the BNC-2140 accessory to connect your analog I/O signals to the DSA devices.
UM.book Page 1 Tuesday, July 14, 1998 10:37 AM Installation and Configuration 2 This chapter explains how to install and configure your BNC-2140 accessory. Installation Note You must turn the power off to your computer before installing the BNC-2140. The following are general installation instructions. 1. Insert either end of your SHC68-C68-A1 analog cable into the 68-pin connector on the BNC-2140. Insert the other end into the 68-pin connector on the DSA plug-in device. 2.
UM.book Page 2 Tuesday, July 14, 1998 10:37 AM Chapter 2 Installation and Configuration ® Figure 2-1.
UM.book Page 1 Tuesday, July 14, 1998 10:37 AM 3 Signal Connections This chapter describes how to connect input and output signals to your BNC-2140. You can connect the external analog signals through six BNC connectors. Four BNC connectors are for input signals and two connectors are for output signals. The SHC68-C68-A1 shielded cable connects the BNC-2140 internal analog signal connector to the DSA plug-in device. A single 68-pin 0.
UM.book Page 2 Tuesday, July 14, 1998 10:37 AM Chapter 3 Signal Connections Table 3-1. BNC Analog I/O Connector Signal Descriptions (Continued) Signal Name Reference +DAC1OUT –DAC1OUT Output +Analog Output Channel 1—This pin supplies the analog non-inverting output channel 1. This signal passes through the internal BNC conductor. –DAC1OUT +DAC1OUT Output –Analog Output Channel 1—This pin supplies the analog inverting output channel 1. This signal passes through the external BNC shell.
UM.book Page 3 Tuesday, July 14, 1998 10:37 AM Chapter 3 Signal Connections Figure 3-1 describes the pin connections on the BNC-2140 68-pin connector.
UM.book Page 4 Tuesday, July 14, 1998 10:37 AM Chapter 3 Signal Connections Note This BNC-2140 pin assignment maps to the pin assignment of the DSA device you are connecting to the BNC-2140. Refer to your DSA device user manual for the pin assignments specific to your device connection. Table 3-2 shows the pin assignments for the internal 68-pin I/O connector. Table 3-2.
UM.book Page 5 Tuesday, July 14, 1998 10:37 AM Chapter 3 Signal Connections The outer shell of the BNC connectors is not GND (0 V). The outer shell of the BNC is not physically connected to the metal box of the BNC-2140. The outer shell is either the inverting differential signal in DIFF mode or is tethered to GND (0 V) through a 50 Ω, 1 W resistor in SE mode. Analog Input Signal Connections The analog input signals for the BNC-2140 device are +ACH<0..3> and –ACH<0..3>.
UM.book Page 1 Tuesday, July 14, 1998 10:37 AM 4 Theory of Operation This chapter contains a functional overview of the BNC-2140.
UM.book Page 2 Tuesday, July 14, 1998 10:37 AM Chapter 4 Theory of Operation Functional Overview Figure 4-1 is a block diagram of the BNC-2140.
UM.book Page 3 Tuesday, July 14, 1998 10:37 AM Chapter 4 Theory of Operation Analog Input Circuitry The BNC-2140 has four identical analog input channels. A principal function of the BNC-2140 is to supply a constant current for ICP type accelerometers and microphone preamplifiers. Many accelerometers use piezoelectric materials to generate a charge that is proportional to the acceleration applied. Although these types of accelerometers have certain advantages, they are very suseptable to external noise.
UM.book Page 4 Tuesday, July 14, 1998 10:37 AM Chapter 4 Theory of Operation Analog Output The BNC-2140 has two analog output channels. The BNC-2140 can also select between DIFF and SE outputs. In DIFF mode, one line connects to the positive output of the channel and the other connects to the negative output of that same channel. You can connect the differential output to either floating or ground-referenced signals.
UM.book Page 1 Tuesday, July 14, 1998 10:37 AM A Specifications This appendix lists the specifications of the BNC-2140 accessory. All specifications are typical at 25° C unless otherwise noted. All specifications are relative to measurement standards and require a 15 minute warm-up period. Specifications do not include transducer error. Analog Input Voltage Input Number of channels ............................... 4 Maximum input voltage (Signal + common mode voltage)..........
UM.book Page 2 Tuesday, July 14, 1998 10:37 AM Appendix A Specifications Temperature coefficient..........................±141 ppm/° C Voltage compliance ................................24 V Excitation overvoltage protection...........±42.4 V (30 Vrms) powered on or off Analog Output Number of channels................................2, see Caution under Analog Output Signal Connections, in Chapter 3, Signal Connections Output coupling ......................................
UM.book Page 1 Tuesday, July 14, 1998 10:37 AM Customer Communication B For your convenience, this appendix contains forms to help you gather the information necessary to help us solve your technical problems and a form you can use to comment on the product documentation. When you contact us, we need the information on the Technical Support Form and the configuration form, if your manual contains one, about your system configuration to answer your questions as quickly as possible.
UM.book Page 2 Tuesday, July 14, 1998 10:37 AM Fax-on-Demand Support Fax-on-Demand is a 24-hour information retrieval system containing a library of documents on a wide range of technical information. You can access Fax-on-Demand from a touch-tone telephone at 512 418 1111. E-Mail Support (Currently USA Only) You can submit technical support questions to the applications engineering team through e-mail at the Internet address listed below.
UM.book Page 3 Tuesday, July 14, 1998 10:37 AM Technical Support Form Photocopy this form and update it each time you make changes to your software or hardware, and use the completed copy of this form as a reference for your current configuration. Completing this form accurately before contacting National Instruments for technical support helps our applications engineers answer your questions more efficiently.
UM.book Page 5 Tuesday, July 14, 1998 10:37 AM Documentation Comment Form National Instruments encourages you to comment on the documentation supplied with our products. This information helps us provide quality products to meet your needs. Title: BNC-2140 User Manual Edition Date: June 1998 Part Number: 321933B-01 Please comment on the completeness, clarity, and organization of the manual.
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UM.book Page 3 Tuesday, July 14, 1998 10:37 AM Glossary C C Celsius channel pin or wire lead to which you apply or from which you read the analog or digital signal. Analog signals can be single-ended or differential. For digital signals, you group channels to form ports. Ports usually consist of either four or eight digital channels.
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UM.book Page 6 Tuesday, July 14, 1998 10:37 AM Glossary I IC integrated circuit ICP Integrated Circuit Piezoelectric—identifies products that operate using a constant current source and returns the output signal in the form of voltage modulation on the same line as the constant current source. IMD intermodulation distortion—the ratio, in dB, of the total rms signal level of harmonic sum and difference distortion products, to the overall rms signal level.
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UM.book Page 8 Tuesday, July 14, 1998 10:37 AM Glossary N NC normally closed, or not connected NIST National Institute of Standards and Technology noise an undesirable electrical signal—Noise comes from external sources such as the AC power line, motors, generators, transformers, fluorescent lights, soldering irons, CRT displays, computers, electrical storms, welders, radio transmitters, and internal sources such as semiconductors, resistors, and capacitors.
UM.book Page 9 Tuesday, July 14, 1998 10:37 AM Glossary peak to peak a measure of signal amplitude; the difference between the highest and lowest excursions of the signal pF pico farad—a farad is a unit used to measure capacitance ppm parts per million pts points R relative accuracy a measure in LSB of the accuracy of an ADC. It includes all non-linearity and quantization errors. It does not include offset and gain errors of the circuitry feeding the ADC.
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UM.book Page 11 Tuesday, July 14, 1998 10:37 AM Glossary V V volts VDC volts direct current VIH volts, input high VIL volts, input low Vin volts in VOH volts, output high VOL volts, output low Vref reference voltage W waveform multiple voltage readings taken at a specific sampling rate working voltage the highest voltage that should be applied to a product in normal use, normally well under the breakdown voltage for safety margin.
UM.book Page 1 Tuesday, July 14, 1998 10:37 AM Index Numbers optional equipment, 1-2 to 1-3 overview, 1-1 requirements for getting started, 1-2 unpacking, 1-2 bulletin board support, B-1 +5 V signal, 68-pin connector signal descriptions (table), 3-4 A +ACH<0..3> signal 68-pin connector signal descriptions (table), 3-4 analog connector (table), 3-1 analog input signal connections, 3-5 –ACH<0..
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