National Instruments NI 5620 User Manual

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Computer-Based Instruments

NI 5620 User Manual

Digitizer for PXI

NI 5620 User Manual

June 2001 Edition

Part Number 322949B-01

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For further support information, see the Technical Support Resources appendix. To comment on the documentation, send e-mail to techpubs@ni.com.

Important Information

Warranty

The NI 5620 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.

The media on which you receive National Instruments software are warranted not to fail to execute programming instructions, due to defects in materials and workmanship, for a period of 90 days from date of shipment, as evidenced by receipts or other documentation. National Instruments will, at its option, repair or replace software media that do not execute programming instructions if National Instruments receives notice of such defects during the warranty period. National Instruments does not warrant that the operation of the software shall be uninterrupted or error free.

A Return Material Authorization (RMA) number must be obtained from the factory and clearly marked on the outside of the package before any equipment will be accepted for warranty work. National Instruments will pay the shipping costs of returning to the owner parts which are covered by warranty.

National Instruments believes that the information in this document is accurate. The document has been carefully reviewed for technical accuracy. In the event that technical or typographical errors exist, National Instruments reserves the right to make changes to subsequent editions of this document without prior notice to holders of this edition. The reader should consult National Instruments if errors are suspected. In no event shall National Instruments be liable for any damages arising out of or related to this document or the information contained in it.

XCEPT AS SPECIFIED HEREIN,NATIONAL INSTRUMENTS MAKES NO W ARRANTIES, EXPRESS OR IMPLIED, AND SPECIFICALLY DISCLAIMS ANY WARRANTY OF

MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE

NATIONAL INSTRUMENTS SHALL BE LIMITED TO THE AMOUNT THERETOFORE PAID B Y THE CUSTOMER.NATIONAL INSTRUMENTS WILL NOT BE LIABLE FOR

DAMAGES RESULTING FROM LOSS OF DATA

. This limitation of the liability of National Instruments will apply regardless ofthe form of action,whether in contract ortort, including

THEREOF

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, PROFITS, USE OF PRODUCTS, OR INCIDENTAL OR CONSEQUENTIAL DAMAGES, EVEN IF ADVISED OF THE POSSIBILITY

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Trademarks

CVI™,LabVIEW™,MITE™, National Instruments™,NI™,ni.com™,PXI™,andRTSI™are trademarks of National Instruments Corporation.

Product and company names mentioned herein are trademarks or trade names of their respective companies.

.CUSTOMER’S RIGHT TO RECOVER DAMAGES CAUSED BY FAULT OR NEGLIGENCE ON THE PART OF

WARNING REGARDING USE OF NATIONAL INSTRUMENTS PRODUCTS

(1) NATIONAL INSTRUMENTS PRODUCTS ARE NOT DESIGNED WITH COMPONENTS AND TESTING FOR A LEVEL OF RELIABILITY SUITABLE FOR USE IN OR IN CONNECTION WITH SURGICAL IMPLANTS OR AS CRITICAL COMPONENTS IN ANY LIFE SUPPORT SYSTEMS WHOSE FAILURE TO PERFORM CAN REASONABLY BE EXPECTED TO CAUSE SIGNIFICANT INJURY TO A HUMAN.

(2) IN ANY APPLICATION, INCLUDING THE ABOVE, RELIABILITY OF OPERATION OF THE SOFTWARE PRODUCTS CAN BE IMPAIRED BY ADVERSE FACTORS, INCLUDING BUT NOT LIMITED TO FLUCTUATIONS IN ELECTRICAL POWER SUPPLY, COMPUTER HARDWARE MALFUNCTIONS, COMPUTER OPERATING SYSTEM SOFTWARE FITNESS, FITNESS OF COMPILERS AND DEVELOPMENT SOFTWARE USED TO DEVELOP AN APPLICATION, INSTALLATION ERRORS, SOFTWARE AND HARDWARE COMPATIBILITY PROBLEMS, MALFUNCTIONS OR FAILURES OF ELECTRONIC MONITORING OR CONTROL DEVICES, TRANSIENT FAILURES OF ELECTRONIC SYSTEMS (HARDWARE AND/OR SOFTWARE), UNANTICIPATED USES OR MISUSES, OR ERRORS ON THE PART OF THE USER OR APPLICATIONS DESIGNER (ADVERSE FACTORS SUCH AS THESE ARE HEREAFTER COLLECTIVELY TERMED “SYSTEM FAILURES”). ANY APPLICATION WHERE A SYSTEM FAILURE WOULD CREATE A RISK OF HARM TO PROPERTY OR PERSONS (INCLUDING THE RISK OF BODILY INJURY AND DEATH) SHOULD NOT BE RELIANT SOLELY UPON ONE FORM OF ELECTRONIC SYSTEM DUE TO THE RISK OF SYSTEM FAILURE. TO AVOID DAMAGE, INJURY, OR DEATH, THE USER OR APPLICATION DESIGNER MUST TAKE REASONABLY PRUDENT STEPS TO PROTECT AGAINST SYSTEM FAILURES, INCLUDING BUT NOT LIMITED TO BACK-UP OR SHUT DOWN MECHANISMS. BECAUSE EACH END-USER SYSTEM IS CUSTOMIZED AND DIFFERS FROM NATIONAL INSTRUMENTS' TESTING PLATFORMS AND BECAUSE A USER OR APPLICATION DESIGNER MAY USE NATIONAL INSTRUMENTS PRODUCTS IN COMBINATION WITH OTHER PRODUCTS IN A MANNER NOT EVALUATED OR CONTEMPLATED BY NATIONAL INSTRUMENTS, THE USER OR APPLICATION DESIGNER IS ULTIMATELY RESPONSIBLE FOR VERIFYING AND VALIDATING THE SUITABILITY OF NATIONAL INSTRUMENTS PRODUCTS WHENEVER NATIONAL INSTRUMENTS PRODUCTS ARE INCORPORATED IN A SYSTEM OR APPLICATION, INCLUDING, WITHOUT LIMITATION, THE APPROPRIATE DESIGN, PROCESS AND SAFETY LEVEL OF SUCH SYSTEM OR APPLICATION.

Compliance

FCC/Canada Radio Frequency Interference Compliance*

Determining FCC Class

The Federal Communications Commission (FCC) has rules to protect wireless communications from interference. The FCC places digital electronics into two classes. These classes are known as Class A (for use in industrial-commercial locations only) or Class B (for use in residential or commercial locations). Depending on where it is operated, this product could be subject to restrictions in the FCC rules. (In Canada, the Department of Communications (DOC), of Industry Canada, regulates wireless interference in much the same way.)

Digital electronics emit weak signals during normal operation that can affect radio, television, or other wireless products. By examining the product you purchased, you can determine the FCC Class and therefore which of the two FCC/DOC Warnings apply in the following sections. (Some products may not be labeled at all for FCC; if so, the reader should then assume these are Class A devices.)

FCC Class A products only display a simple warning statement of one paragraph in length regarding interference and undesired operation. Most of our products are FCC Class A. The FCC rules have restrictions regarding the locations where FCC Class A products can be operated.

FCC Class B products display either a FCC ID code, starting with the letters EXN, or the FCC Class B compliance mark that appears as shown here on the right.

Consult the FCC web site

http://www.fcc.gov

FCC/DOC Warnings

This equipment generates and uses radio frequency energyand, if not installed and used in strict accordance with the instructions in this manual and the CE Mark Declaration of Conformity**, may cause interference to radio and television reception. Classification requirements are the same for the Federal Communications Commission (FCC) and the Canadian Department of Communications (DOC).

Changes or modifications not expressly approved by National Instruments could void the user’s authority to operate the equipment under the FCC Rules.

for more information.

Class A

Federal Communications Commission

This equipment has been tested and found to comply with the limits for a Class A digital device, pursuant to part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference when the equipment is operated in a commercial environment. This equipment generates, uses, and can radiate radio frequency energy and, if not installed and used in accordance with the instruction manual, may cause harmful interference to radio communications. Operation of this equipment in a residential area is likely to cause harmful interference in which case the user will be required to correct the interference at his own expense.

Canadian Department of Communications

This Class A digital apparatus meets all requirements of the Canadian Interference-Causing Equipment Regulations.

Cet appareil numérique de la classe A respecte toutes les exigences du Règlement sur le matériel brouilleur du Canada.

Class B

Federal Communications Commission

This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation. This equipment generates, uses and can radiate radio frequency energy and, if not installed and used in accordance with the instructions, may cause harmful interference to radio communications. However, there is no guarantee that interference will not occur in a particular installation. If this equipment does cause harmful interference to radio or television reception, which can be determined by turning the equipment off and on, the user is encouraged to try to correct the interference by one or more of the following measures:

• Reorient or relocate the receiving antenna.

• Increase the separation between the equipment and receiver.

• Connect the equipment into an outlet on a circuit different from that to which the receiver is connected.

• Consult the dealer or an experienced radio/TV technician for help.

Canadian Department of Communications

This Class B digital apparatus meets all requirements of the Canadian Interference-Causing Equipment Regulations. Cet appareil numérique de la classe B respecte toutes les exigences du Règlement sur le matériel brouilleur du Canada.

Compliance to EU Directives

Readers in the European Union (EU) must refer to the Manufacturer's Declaration of Conformity (DoC) for information** pertaining to the CE Mark compliance scheme. The Manufacturer includes a DoC for most every hardware product except for those bought for OEMs, if also available from an original manufacturer that also markets in the EU, or where compliance is not required as for electrically benign apparatus or cables.

To obtain the DoC for this product, click Declaration of Conformity at by product family. Select the appropriate product family, followed by your product, and a link to the DoC appears in Adobe Acrobat format. Click the Acrobat icon to download or read the DoC.

* Certain exemptions may apply in the USA, see FCC Rules §15.103 Exempted devices,and§15.105(c). Also available in

sections of CFR 47.

** The CE Mark Declaration of Conformity will contain important supplementary information and instructions for the user or

installer.

ni.com/hardref.nsf/

. This website lists the DoCs

Conventions

The following conventions are used in this manual:

<> Angle brackets that contain numbers separated by an ellipsis represent a

range of values associated with a bit or signal name—for example, DBIO<3..0>.

» The » symbol leads you through nested menu items and dialog box options

to a final action. The sequence File»Page Setup»Options directs you to pull down the File menu, select the Page Setup item, and select Options from the last dialog box.

This icon denotes a note, which alerts you to important information.

This icon denotes a caution, which advises you of precautions to take to avoid injury, data loss, or a system crash.

bold Bold text denotes items that you must select or click on in the software,

such as menu items and dialog box options. Bold text also denotes parameter names.

italic Italic text denotes variables, emphasis, a cross reference, or an introduction

to a key concept. This font also denotes text that is a placeholder for a word or value that you must supply.

monospace

Text in this font denotes text or characters that you should enter from the keyboard, sections of code, programming examples, and syntax examples. This font is also used for the proper names of disk drives, paths, directories, programs, subprograms, subroutines, device names, functions, operations, variables, filenames and extensions, and code excerpts.

Chapter 1 Taking Measurements with the NI 5620

Installing the Software and Hardware ...........................................................................1-1

Acquiring Data with Your NI 5620 ...............................................................................1-2

Programmatically Controlling Your NI 5620..................................................1-2

Safety Information .........................................................................................................1-2

Chapter 2 Hardware Overview

How the NI 5620 Works................................................................................................2-1

Connecting Signals..........................................................................................2-2

Conditioning the Signal—Impedance, Dither, Gain, and AC Coupling.........2-3

Input Impedance................................................................................2-3

Dither ................................................................................................2-3

Digitizing the Signal—The ADC .................................................................... 2-3

Incorporating the DDC....................................................................................2-4

Storing Data in Memory.................................................................................. 2-4

Block Diagram...............................................................................................................2-5

Other Features................................................................................................................2-6

Multiple-Record Acquisitions ......................................................................... 2-6

Triggering ........................................................................................................2-7

Calibration .....................................................................................................................2-7

Synchronizing Multiple PXI Devices ............................................................................ 2-8

Appendix A Specifications

Appendix B Technical Support Resources

Glossary

Index

Taking Measurements with the NI 5620

Thank you for buying a National Instruments (NI) 5620 digitizer.

This chapter provides information on installing, connecting signals to,

and acquiring data from the NI 5620.

The NI 5620 has the following features:

• One 14-bit, 64 MS/s analog-to-digital converter (ADC)

• Deep onboard sample memory (amount varies depending on model)

Installing the Software and Hardware

For step-by-step instructions for installing the NI-SCOPE software and the

NI 5620, see the Where to Start with Your NI 5620 Digitizer document.

There are two main steps involved in installation:

1. Install the NI-SCOPE driver. You use NI-SCOPE to write programs to control your NI 5620 in different application development environments (ADEs).

2. Install your Spectral Measurements Toolset (SMT) CD, if included. The SMT provides frequency-domain functionality and examples.

3. Install your NI 5620. See the Where to Start with Your NI 5620 Digitizer document.

Chapter 1 Taking Measurements with the NI 5620

Acquiring Data with Your NI 5620

You can acquire data programmatically either by writing an application for your NI 5620 or using one of the examples that ships with NI-SCOPE.

Programmatically Controlling Your NI 5620

To help you get started programming your NI 5620, the software comes with examples that you can use or modify.

For time-domain examples, go to the following default locations:

• LabVIEW—Open the Functions palette, and go to Instrument I/O» Instrument Drivers»NI SCOPE»IF Digitizers.

• C and Visual Basic—Go to

• LabWindows/CVI—Go to

cvi\samples\Niscope

vxipnp\winXX\Niscope\Examples

For frequency-domain LabVIEW examples, go to

Spectral Measurements Toolset

go to

For more detailed function reference help, see the NI-SCOPE VI Reference Help, located at Start»Programs»National Instruments»NI-SCOPE.

Safety Information

The following paragraphs contain important safety information that must be followed during installation and use of the device.

Caution

of the device may result in a hazard. The safety protection built into the device may be compromised if it is damaged in any way. If the device is damaged, return it to NI for repair.

Caution

60 VDC), you must connect a safety earth ground wire. See Appendix A, Specifications, for maximum voltage ratings.

Caution

modules, accessories, and cables specified in the installation instructions. All covers and filler panels must be installed during operation of the device.

Do not operate the device in a manner not specified in the user manual. Misuse

If the device is rated for use with hazardous voltages ( >30 Vrms, 42.4 Vpp, or

Do not substitute parts or modify the device. Use the device only with chassis,

cvi\samples\smt

LabVIEW 6\examples\

. For LabWindows/CVI examples,

NI 5620 User Manual 1-2 ni.com

Chapter 1 Taking Measurements with the NI 5620

Caution

Do not operate the device in an explosive atmosphere or where there may be flammable gases or fumes. The device can only be operated at or below pollution degree 2, as stated in Appendix A, Specifications. Pollution is foreign matter, solid, liquid, or gas that may produce a reduction of dielectric strength or surface resistivity. The following is a description of pollution degrees:

• Pollution degree 1: No pollution or only dry, non-conductive pollution occurs. The pollution has no influence.

• Pollution degree 2: Normally only non-conductive pollution occurs. Occasionally, however, a temporary conductivity caused by condensation must be expected.

• Pollution degree 3: Conductive pollution occurs, or dry, non-conductive pollution occurs, which becomes conductive due to condensation.

Caution

Signal connections must be insulated for the maximum voltage for which the device is rated. Do not exceed the maximum ratings for the device. Remove power from signal lines before connection to or disconnection from the device.

Caution

This device can only be operated at installation category I, as stated in Appendix A, Specifications. The following is a description of installation categories:

• Installation category IV is for measurements performed at the source of the low-voltage installation. Examples are electricity meters and measurements on primary over current protection devices and ripple control units.

• Installation category III is for measurements performed in the building installation. Examples are measurements on distribution boards, circuit-breakers, wiring, including cables, bus-bars, junction boxes, switches, socket-outlets in the fixed installation, and equipment for industrial use and some other equipment such as stationary motors with permanent connection to the fixed installation.

• Installation category II is for measurements performed on circuits directly connected to the low voltage installation. Examples are measurements on household appliances, portable tools and similar equipment.

• Installation category I is for measurements performed on circuits not directly connected to MAINS. Examples are measurements on circuits not derived from MAINS, and specially protected (internal) MAINS-derived circuits.

Caution

Clean the device with a soft non-metallic brush. The device must be completely

dry and free from contaminants before returning it to service.

Hardware Overview

This chapter provides an overview of the features and functionality of the NI 5620.

How the NI 5620 Works

A signal follows this path through the NI 5620 to your host computer:

1. The signal enters the NI 5620 through the analog front panel connector, INPUT. To find more about the front panel, see the

Connecting Signals section later in this chapter.

2. The signal is filtered and conditioned. Gain and dither are applied to the signal. See the Conditioning the Signal—Impedance, Dither, Gain,

and AC Coupling section for more information.

3. The ADC converts the signal from analog to digital. Refer to the

Digitizing the Signal—The ADC section for more information.

4. (Optional) The digital downconverter (DDC) digitally “zooms in” on data. See the Incorporating the DDC section.

5. The data is sent to onboard memory (the buffer). See the Storing Data

in Memory section for additional information.

6. The data is transferred to your host computer.

Analog

Input

Filtering/

Conditioning

ADC

DDC

(Optional)

Figure 2-1. Basic Signal Flow

Onboard

Memory

P X

B u

Chapter 2 Hardware Overview

Connecting Signals

Figure 2-2 shows the NI 5620 front panel, which contains three connectors—two SMA connectors and an SMB connector.

One ofthe SMA connectors, INPUT, is for attaching the analog input signal you wish to measure. The second SMA connector, REF CLK IN, is a 50 Ω,10 MHz, AC-coupled reference input. The SMB connector, PFI1, is for external digital triggers.

5620

64 MS/s Digitizer

INPUT

+20 dBm MAX

REF CLK IN

+16 dBm MAX

PFI 1

Figure 2-2. NI 5620 Front Panel

NI 5620 User Manual 2-2 ni.com

Chapter 2 Hardware Overview

Conditioning the Signal—Impedance, Dither, Gain, and AC Coupling

To minimize distortion, signals receive a minimal amount of conditioning. There is one set gain, and all signals are AC coupled, meaning that the NI 5620 rejects any DC portion of a signal. The NI 5620 also has a set input impedance of 50 Ω and applies dither to the configurable signal.

Input Impedance

The input impedance of the NI 5620 is 50 Ω. The output impedance of the source connected to the NI 5620 and the input impedance of the NI 5620 form an impedance divider, which attenuates the input signal according to the following formula:



-------------------

×=



RinR

where V

is the measured voltage

is the unloaded source voltage

is the output impedance of the external device

is the input impedance of the NI 5620

If the source whose output you are measuring has an output impedance other than 50 Ω, your measurements will be affected by this impedance divider. For example, if the device has 75 Ω output impedance, your measured signal will be 80% of the value it would have been at 50 Ω.

Dither

Dither is random noise added to the input signal between 0 and 5 MHz. Dither lowers the amount of distortion caused by differential nonlinearity in the ADC when a signal is digitized. When an FFT is applied to the signal, this random noise cancels out most of the distortion created by differential nonlinearity. Dither is not automatically applied, but you can enable it in software.

Digitizing the Signal—The ADC

Regardless of your requested sample rate, the NI 5620 ADC is always running at 64 MS/s. If you request a rate less than 64 MS/s, the timing engine of the NI 5620 stores only 1 sample in a group of n samples, effectively reducing the sample rate to 64/n MS/s.

Chapter 2 Hardware Overview

Incorporating the DDC

You may optionally route the data through the DDC before storing it in onboard memory.

The DDC is a digital signal processing (DSP) chip, the Intersil HSP50214B. The first stage uses a digital quadrature mixer that shifts a signal to baseband from any frequency within the digitizer’s range. The next stage decimates (reduces the sample rate) by an integer from 4 to 16384. A series of programmable digital lowpass filters prior to each stage of decimation prevents aliasing when the sample rate is reduced. The decimated data may be retrieved as in-phase and quadrature, or as phase and magnitude. A discriminator allows you to take the derivative of the phase to demodulate an FM signal.

By mixing, filtering, and decimating the sampled data, the DDC allows you to zoom in on a band of frequencies much narrower than the Nyquist band of the ADC. The lower sample rate means that signals of longer duration can be stored in the same amount of memory. For spectral analysis, a smaller, faster FFT may be used to look at only the band passed through the DDC.

Refer to the NI-SCOPE VI Reference Help for specific DDC attributes you can use to program your NI 5620. If you installed the included measurement software, there is also online help for LabVIEW users using the DDC.

Storing Data in Memory

Samples are acquired into onboard memory on the NI 5620 before being transferred to the host computer. The minimum size for a buffer is approximately 256 samples, although you can specify smaller buffers in software. When specifying a smaller buffer size, the minimum number of points are still acquired into onboard memory, but only the specified number of points are retrieved into the host computer’s memory.

During the acquisition, samples are stored in a circular buffer that is continually rewritten until a trigger is received. After the trigger is received, the NI 5620 continues to acquire posttrigger samples if you have specified a posttrigger sample count. The acquired samples are placed into onboard memory. The number of posttrigger or pretrigger samples is limited only by the amount of onboard memory.

NI 5620 User Manual 2-4 ni.com

Block Diagram

Chapter 2 Hardware Overview

This block diagram is intended for advanced users. An explanation of some of these features follows.

Analog

Input

(INPUT)

10 MHz

Reference

Input

(REF CLK IN)

EXT TRIG

(PFI)

Filter

PLL

Dither

Phase

Detector

ADC

Voltage

Controlled

Oscillator

External Trigger

Digital

Downconverter

Data Path

Logic

CalDAC

Onboard

Memory

TIO

(Timing and Control)

Trigger and

Clock Routing

Figure 2-3. Block Diagram

MITE

(PXI Interface)

P X

CLK 10

PXI Trigger

The digital downconverter is a digital signal processor (DSP) that allows you to digitally zoom in on data, which reduces the amount of data transferred into memory and speeds up the rate of data transfer. The digital downconverter does this by frequency-translating, filtering, and decimating signals after they go through the ADC. See the Incorporating the DDC section for more information.

The PLL uses a phase dectetor to synchronize the acquisition clock to either a 10 MHz reference clock supplied through REF CLK IN or to the CLK 10 signal from the PXI backplane. You can also choose to leave the

Chapter 2 Hardware Overview

acquisition clock in a free-running state, in which the acquisition clock is not synchronized to any external reference.

The voltage controlled crystal oscillator (VCXO) is a 64 MHz clock.

The trigger and clock routing area directs clock signals and triggers.

The TIO is the timing engine used for the NI 5620.

The MITE is the PXI bus interface. The MITE provides high-speed direct memory access (DMA) transfers from the NI 5620 to the host computer’s memory.

Other Features

This section contains information on other features on the NI 5620.

Multiple-Record Acquisitions

After the trigger has been received and the posttrigger samples have been stored, you can configure the NI 5620 to begin another acquisition that is stored in another memory record on the device. This process is a multiple-record acquisition. To perform multiple-record acquisitions, configure the NI 5620 to the number of records to be acquired before starting the acquisition. The NI 5620 acquires an additional record each time a trigger is accepted until all the requested records have been stored in memory. After the initial setup, this process does not require software intervention.

Between each record, there is a dead time during which the trigger is not accepted. If the record length is greater than 80 µs, this dead time will be 500 ns. If, however, the record length is less than 80 µs, the dead time will be 80 µs. During this time, the memory controller sets up for the next record. There may also be additional dead time while the minimum number of pretrigger samples are being acquired. Figure 2-4 shows a timing diagram of a multiple-record acquisition.

NI 5620 User Manual 2-6 ni.com

Chapter 2 Hardware Overview

Triggering

Trigger

Acquisition

In Progress

Buffer

Figure 2-4.

1 2 3

500 ns

= Trigger Not Accepted (Pretrigger Points Not Acquired)

= Trigger Not Accepted (500 ns Dead Time)

= Trigger Not Accepted (Acquisition in Progress)

= Trigger Accepted

Multiple-Record Acquisition Timing Diagram

You can externally trigger the NI 5620 through the digital line, PFI1. You can also use software to trigger it. Figure 2-5 shows the different trigger sources. The digital triggers are TTL-level signals with a minimum pulse-width requirement of 100 ns or 16 ns times the DDC decimation.

Software

RTSI <0..7>

PFI1

Trigger

PXI Star

Figure 2-5. Digital Trigger Sources

Calibration

Although the NI 5620 is factory calibrated, it needs periodic calibration to verify that it is still within the specified accuracy. For more information on calibration, contact NI or visit the NI Web site at

ni.com

Chapter 2 Hardware Overview

Synchronizing Multiple PXI Devices

The NI 5620 uses a PLL to synchronize the 64 MHz sample clock to a 10 MHz reference clock. You can either supply the reference clock through the SMA connector (REF CLK IN) on the front panel or use the system reference clock on the PXI backplane.

The PXI bus and the NI 5620 have the following timing and triggering features that you can use for synchronizing multiple digitizers:

• System Reference Clock—Thisisa10MHzclockonthePXI backplane with ±100 ppm accuracy. It is independently distributed to each PXI peripheral slot through equal-length traces with a skew of less than 1 ns between slots. Multiple devices can use this common timebase for synchronization. This allows each NI 5620 to phase lock to the system reference clock.

• SMA connector (REF CLK IN)—This is a 10 MHz reference input that you can use to connect your external frequency source for synchronization.

NI 5620 User Manual 2-8 ni.com

Specifications

This appendix lists the specifications of the NI 5620. These specifications are typical at 25 °C unless otherwise specified.

General Specifications

Number of channels ............................... 1

Resolution .............................................. 14 bits

Max sample rate .....................................64 MS/s (also integer

Onboard memory

Using DDC (complex data) ............8 MS

Not using DDC ............................... 16 MS

Input

Signal level

Nominal .......................................... 0 dBm (±0.316 V)

Full-Scale ........................................ +10 dBm (±1.000 V)

Max with dither enabled ................. +9 dBm (±0.891 V)

Max non-operating input level........ +20 dBm (±3.16 V)

Max DC input voltage..................... ±2 V

divisions of 64 MS/s)

Input impedance..................................... 50 Ω

Coupling................................................. AC

Fully specified frequency range............. 5 to 25 MHz

Analog bandwidth (–3 dB range)...........25 kHz to 36 MHz

Appendix A Specifications

Frequency

VSWR

0.1 to 25 MHz..................................< 1.5:1

25 to 32 MHz...................................< 3:1

Dither (can be disabled)

Frequency range ..............................15 kHz to 3 MHz

Internal Sample Clock

Frequency ........................................64 MHz / n, where 1 ≤ n ≤ 2

Accuracy..........................................< ±12 ppm (after calibration)

Noise sidebands

Offset Density

100 Hz < –100 dBc/Hz

1kHz < –120 dBc/Hz

10 kHz < –130 dBc/Hz

Amplitude

100 kHz < –130 dBc/Hz

Residual FM ...........................................< 2 Hz

pk–pk

in 10 ms

Average noise density............................. –134 dBm/Hz

Spurious responses (0 dBm signal)

5 to 25 MHz, dither enabled............< –80 dBc

0.1to32MHz,ditherdisabled........–80 dBc

Residual responses (input terminated)....< –85 dBm

Frequency response (5 to 25 MHz)

Relative (to response at 15 MHz) ....Less than ±0.25 dB

Absolute...........................................Less than ±0.5 dB

Absolute, using calibration table .....Less than ±0.1 dB

Absolute (0.1 to 32 MHz)................±2.5 dB

Relative

(0.1 to 32 MHz, to 15 MHz)............±1.5 dB

NI 5620 User Manual A-2 ni.com

Appendix A Specifications

-10

-20

-30

-40

-50

-60

-70 0

Frequency (MHz)

100

Figure A-1. Frequency Response from 5 to 100 MHz

Phase

Group delay variation

(5 to 25 MHz)......................................... 9 ns

pk-to-pk

Group delay variation

(0.5 to 30 MHz)......................................26 ns

pk-to-pk

DDC

Decimation rate with

installed software ................................... 32 to 4096

DDC tuning resolution ........................... 0.014901 Hz

Appendix A Specifications

Triggering

PFI 1 Input/Output

Modes .....................................................Immediate, software, digital

Sources....................................................PFI 1, RTSI<0..7>, PXI star

Export .....................................................RTSI<0..7>, PFI 1

Slope .......................................................Rising, falling

Pretrigger depth ......................................Up to 16 MS

Posttrigger depth.....................................Up to 16 MS

Minimum pulse width.............................100 ns

PFI 1 Connector......................................SMB male

Trigger level ...........................................TTL

Max input voltage...................................5.5 V

External Frequency Reference Input

Connector (REF CLK IN) ......................SMA female

Impedance...............................................50 Ω

Input amplitude.......................................–5 to +15 dBm

Max nonoperating input level.................+16 dBm

Max DC input voltage ............................±10 VDC

Frequency ...............................................10 MHz

Required frequency accuracy .................±40 ppm

NI 5620 User Manual A-4 ni.com

Environmental Specifications

Calibration interval ................................ 1 year

Warm-up time ........................................ 10 minutes

Operating environment

Ambient temperature ...................... 0 to 50 °C

Humidity ......................................... 10 to 90%, noncondensing

Storage environment

Storage temperature ........................ –20 to 70 °C

Humidity ......................................... 5 to 95%, noncondensing

Maximum altitude .................................. 2000 meters

Pollution degree .................................... 2

Indoor use only

Power Requirements

+3.3 VDC (±5%).................................... < 600 mA, 400 mA typical

Appendix A Specifications

+5 VDC (±5%)....................................... < 1.5 A, 1 A typical

+12 VDC (±5%)..................................... < 450 mA, 330 mA typical

–12 VDC (±5%)..................................... < 35 mA, 24 mA typical

Maximum Working Voltage

Channel to earth ..................................... 2 V, Installation Category I

Safety

Meets the requirements of the following standards for safety for electrical equipment for measurement, control, and laboratory use:

EN 61010-1:1993/A2:1995, IEC 61010-1:1990/A2:1995, UL 3101-1:1993, UL 3111-1:1994, UL 3121:1998, CAN/CSA C22.2 no. 1010.1:1992/A2:1997 d.

Appendix A Specifications

Electromagnetic Compatibility

CE, C-Tick, and FCC Part 15 (Class A) compliant

Electrical emissions ................................EN 55011 Class A at 10 m FCC

Electrical immunity ................................Evaluated to EN

Note

For full EMC compliance, you must operate this device with shielded cabling. In addition, all covers and filler panels must be installed. See the Declaration of Conformity (DoC) for this product for any additional regulatory compliance information. To obtain the DoC for this product, click Declaration of Conformity at Web site lists the DoCs by product family. Select the appropriate product family, followed by your product, and a link to the DoC (in Adobe Acrobat format) appears. Click the Acrobat icon to download or read the DoC.

Dimensions

PXI-5620 (1 PXI slot).............................10 cm by 16 cm by 2.0 cm

Part 15A above 1 GHz

61326:1997/A1:1998, Table 1

ni.com/hardref.nsf/

(3.9inby6.3inby0.8in)

.This

Certifications and Compliances

CE Mark Compliance

Conductive Immunity

When tested as specified in EN 61000-4-6 at 3 Vrms, the spurious response will be within specifications except at the test frequency. A spurious signal of up to –45 dBm may appear at the test frequency.

NI 5620 User Manual A-6 ni.com

Technical Support Resources

Web Support

National Instruments Web support is your first stop for help in solving installation, configuration, and application problems and questions. Online problem-solving and diagnostic resources include frequently asked questions, knowledge bases, product-specific troubleshooting wizards, manuals, drivers, software updates, and more. Web support is available through the Technical Support section of

NI Developer Zone

ni.com

The NI Developer Zone at building measurement and automation systems. At the NI Developer Zone, you can easily access the latest example programs, system configurators, tutorials, technical news, as well as a community of developers ready to share their own techniques.

Customer Education

National Instruments provides a number of alternatives to satisfy your training needs, from self-paced tutorials, videos, and interactive CDs to instructor-led hands-on courses at locations around the world. Visit the Customer Education section of syllabi, training centers, and class registration.

System Integration

If you have time constraints, limited in-house technical resources, or other dilemmas, you may prefer to employ consulting or system integration services. You can rely on the expertise available through our worldwide network of Alliance Program members. To find out more about our Alliance system integration solutions, visit the System Integration section of

ni.com

ni.com/zone

ni.com

is the essential resource for

for online course schedules,

Appendix B Technical Support Resources

Worldwide Support

National Instruments has offices located around the world to help address your support needs. You can access our branch office Web sites from the Worldwide Offices section of up-to-date contact information, support phone numbers, e-mail addresses, and current events.

If you have searched the technical support resources on our Web site and still cannot find the answers you need, contact your local office or National Instruments corporate. Phone numbers for our worldwide offices are listed at the front of this manual.

ni.com

. Branch office Web sites provide

NI 5620 User Manual B-2 ni.com

Glossary

Prefix Meanings Value

p- pico 10

n- nano- 10

µ- micro- 10

m- milli- 10

k- kilo- 10

M- mega- 10

G- giga- 10

Numbers/Symbols

% percent

+ positive of, or plus

–12

–9

– 6

–3

– negative of, or minus

/per

° degree

± plus or minus

Ω ohm

< less than

A amperes

A/D analog-to-digital

AC alternating current

Glossary

AC coupled allowing the transmission of AC signals while blocking DC signals

ADC analog-to-digital converter—an electronic device, often an integrated

circuit, that converts an analog voltage to a digital number

ADC resolution the resolution of the ADC, which is measured in bits. An ADC with

16 bits has a higher resolution, and thus a higher degree of accuracy, than a 12-bit ADC.

ADE application development environment

alias a false lower frequency component that appears in sampled data acquired

at too low a sampling rate

amplification a type of signal conditioning that improves accuracy in the resulting

digitized signal and reduces noise

amplitude flatness a measure of how close to constant the gain of a circuit remains over a range

of frequencies

analog bandwidth the range of frequencies to which a measuring device can respond

attenuate to decrease the amplitude of a signal

bbit—one binary digit, either 0 or 1

Bbyte—eight related bits of data, an eight-bit binary number. Also used to

denote the amount of memory required to store one byte of data.

bus the group of conductors that interconnect individual circuitry in a computer.

Typically, a bus is the expansion vehicle to which I/O or other devices are connected. An example of the PC bus is the PCI bus.

CCelsius

CMOS complementary metal oxide semiconductor. A process used in making

chips.

Glossary

CMRR common-mode rejection ratio—a measure of an instrument’s ability to

reject interference from a common-mode signal, usually expressed in decibels (dB)

coupling the manner in which a signal is connected from one location to another

data path logic a signal router

dB decibel—the unit for expressing a logarithmic measure of the ratio of two

signal levels: dB=20log10 V1/V2, for signals in volts

dBm Decibels with reference to 1 mW, the standard unit of power level used in

RF and microwave work. Using this standard, 0 dBm equals 1 mW, 10 dBm equals 10 mW, and so on. In a 50 Ω system, 0 dBm equals ±0.224 V

DC direct current

DDC See digital downconverter.

dead time a period of time in which no activity can occur

rms

default setting a default parameter value recorded in the driver. In many cases, the default

input of a control is a certain value (often 0) that means use the current default setting.

differential input an analog input consisting of two terminals, both of which are isolated from

computer ground, whose difference is measured

digital downconverter a DSP that selects only a narrow portion of the frequency spectrum, thereby

eliminating unwanted data before it is transferred into memory

dither random noise added to a signal before it is digitized to minimize distortion

created by differential nonlinearity

DMA direct memory access—a method by which data is transferred to/from

computer memory from/to a device or memory on the bus while the processor does something else. DMA is the fastest method of transferring data to/from computer memory.

double insulated a device that contains the necessary insulating structures to provide electric

shock protection without the requirement of a safety ground connection

Glossary

drivers software that controls a specific hardware instrument

DSP digital signal processor

EEPROM electrically erasable programmable read-only memory—ROM that can be

erased with an electrical signal and reprogrammed

FFT fast Fourier transform

filtering a type of signal conditioning that allows you to remove unwanted signals or

frequency components from the signal you are trying to measure

gain the factor by which a signal is amplified, sometimes expressed in decibels

hardware the physical components of a computer system, such as the circuit boards,

plug-in boards, chassis, enclosures, peripherals, cables, and so on

harmonics multiples of the fundamental frequency of a signal

Hz hertz—the number of scans read or updates written per second

I/O input/output—the transfer of data to/from a computer system involving

communications channels, operator interface devices, and/or data acquisition and control interfaces

impedance resistance

in. inch or inches

inductance the relationship of induced voltage to current

Glossary

input bias current the current that flows into the inputs of a circuit

input impedance the measured resistance and capacitance between the input terminals of a

circuit

instrument driver a set of high-level software functions that controls a specific plug-in DAQ

board. Instrument drivers are available in several forms, ranging from a function callable language to a virtual instrument (VI) in LabVIEW.

interrupt a computer signal indicating that the CPU should suspend its current task

to service a designated activity

interrupt level the relative priority at which a device can interrupt

ISA industry standard architecture

LabVIEW a graphical programming language

LSB least significant bit

m meters

M (1) Mega, the standard metric prefix for 1 million or 10

units of measure such as volts and hertz; (2) mega, the prefix for 1,048,576,

or 2

, when used with B to quantify data or computer memory

MB megabytes of memory

MITE MXI Interface to Everything—a custom ASIC designed by NI that

implements the PCI bus interface. The MITE supports bus mastering for high-speed data transfers over the PCI bus.

multiple-record

multiple, distinct chunks (or records) of data

acquisition

,whenusedwith

Glossary

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. Noise corrupts signals you are trying to send or receive.

Ohm’sLaw (R=V/I)—the relationship of voltage to current in a resistance

onboard memory the device memory. Onboard memory is distinct from computer memory.

overrange a segment of the input range of an instrument outside of the normal

measuring range. Measurements can still be made, usually with a degradation in specifications.

PCI Peripheral Component Interconnect—a high-performance expansion bus

architecture originally developed by Intel to replace ISA and EISA; it is achieving widespread acceptance as a standard for PCs and workstations and offers a theoretical maximum transfer rate of 132 Mbytes/s

peak value the absolute maximum or minimum amplitude of a signal (AC + DC)

PFI Programmable Function Input

PLL phase-locked loop

PXI PCI eXtensions for Instrumentation. PXI is an open specification that

builds on the CompactPCI specification by adding instrumentation-specific features.

Rresistor

RAM random-access memory

Glossary

random interleaved sampling

real-time sampling sampling that occurs immediately

record length the size of a chunk (or record) of data that can be or has been acquired by a

resolution the smallest signal increment that can be detected by a measurement

rms root mean square—a measure of signal amplitude; the square root of the

ROM read-only memory

method of increasing sample rate by repetitively sampling a repeated waveform

device

system. Resolution can be expressed in bits, in proportions, or in percent of full scale. For example, a system has 12-bit resolution, one part in 4,096 resolution, and 0.0244% of full scale.

average value of the square of the instantaneous signal amplitude

s seconds

S samples

S/s samples per second—used to express the rate at which an instrument

samples an analog signal

sample rate the speed that a device can acquire data

sense in four-wire resistance the sense measures the voltage across the resistor

being excited by the excitation current

settling time the amount of time required for a voltage to reach its final value within

specified limits

Shannon Sampling Theorem

source impedance a parameter of signal sources that reflects current-driving ability of voltage

system noise a measure of the amount of noise seen by an analog circuit or an ADC when

a theorem stating that a signal must be sampled at least twice as fast as the bandwidth of the signal to accurately reconstruct the signal as a waveform

sources (lower is better) and the voltage-driving ability of current sources (higher is better)

the analog inputs are grounded

Glossary

temperature coefficient

the percentage that a measurement will vary according to temperature. See also thermal drift.

thermal drift measurements that change as the temperature varies

thermal EMFs thermal electromotive forces—voltages generated at the junctions of

dissimilar metals that are functions of temperature. Also called thermoelectric potentials.

thermoelectric

See thermal EMFs.

potentials

TIO timing input/output. The engine used for timing and control.

transfer rate the rate, measured in bytes/s, at which data is moved from source to

destination after software initialization and set up operations; the maximum rate at which the hardware can operate

trigger any event that causes or starts some form of data capture

TTL transistor-transistor logic. A digital circuit composed of bipolar transistors

wired in a certain manner.

V volts

error

volts alternating current

volts direct current

voltage error

vertical sensitivity the smallest voltage change a device can detect

VI virtual instrument—(1) a combination of hardware and/or software

elements, typically used with a PC, that has the functionality of a classic stand-alone instrument (2) a LabVIEW software module (VI), which consists of a front panel user interface and a block diagram program

rms

volts, root mean square value

waveform shape the shape the magnitude of a signal creates over time

working voltage the highest voltage that should be applied to a product in normal use,

normally well under the breakdown voltage for safety margin

Glossary

Index

AC coupling, 2-3 acquiring data

multiple-record acquisitions, 2-6

programmatically, 1-2 ADC, 2-3 amplitude specifications, A-2 to A-3

basic signal flow (figure), 2-1 block diagram for NI 5620 digitizer, 2-5 to 2-6

calibration, 2-7 certifications and compliances, A-6 conditioning signals

AC coupling, 2-3

dither, 2-3

gain, 2-3

input impedance, 2-3 conductive immunity, A-6 connecting signals, 2-2 conventions used in manual, vi customer education, B-1

data, storing in memory, 2-4 data acquisition

multiple-record acquisitions, 2-6

programmatically, 1-2 DDC (digital downconverter)

incorporating, 2-4

overview, 2-4

specifications, A-3

dead time, in multiple-record acquisitions, 2-7 digital downconverter. See DDC (digital

downconverter). digitizing the signal (ADC), 2-3 dither, 2-3

electromagnetic compatibility, A-6 environmental specifications, A-5 external frequency reference input

specifications, A-4

frequency specifications, A-2

gain, 2-3

hardware installation, 1-1 hardware overview, 2-1 to 2-8

basic signal flow (figure), 2-1 block diagram, 2-5 to 2-6 calibration, 2-7 conditioning signals

AC coupling, 2-3 dither, 2-3 gain, 2-3

input impedance, 2-3 connecting signals, 2-2 digitizing the signal (ADC), 2-3 incorporating DDC, 2-4 multiple-record acquisitions, 2-6 to 2-7

Index

signal path from NI 5620 to host computer, 2-1

storing data in memory, 2-4 synchronizing multiple PXI devices, 2-8 triggering, 2-7

incorporating DDC, 2-4 input impedance, 2-3 input specifications, A-1 to A-2 installing software and hardware, 1-1

maximum working voltage, A-5 MITE interface, 2-6 multiple-record acquisitions

overview, 2-6 timing diagram (figure), 2-7

NI 5620 digitizer. See also hardware

overview; specifications.

acquiring data, 1-2 block diagram, 2-5 to 2-6 controlling programmatically, 1-2 front panel (figure), 2-2 installing software and hardware, 1-1

safety information, 1-2 to 1-3 NI Developer Zone, B-1 NI-SCOPE driver, 1-1

PFI 1 input/output specifications, A-4 phase detector, 2-5 phase specifications, A-3 phase-locked loop (PLL), 2-5 power requirement specifications, A-5

programmatically controlling the NI 5620, 1-2 PXI devices, multiple, synchronizing, 2-8

REF CLK IN connector, 2-2, 2-8

safety information, 1-2 to 1-3 safety specifications, A-5 signal conditioning

AC coupling, 2-3 dither, 2-3 gain, 2-3

input impedance, 2-3 signal path from NI 5620 to host computer, 2-1 SMA connectors, 2-2, 2-8 software installation, 1-1 specifications

amplitude, A-2 to A-3

certifications and compliances, A-6

conductive immunity, A-6

DDC, A-3

dimensions, A-6

electromagnetic compatibility, A-6

environmental, A-5

external frequency reference input, A-4

frequency, A-2

general, A-1 to A-2

input, A-1 to A-2

maximum working voltage, A-5

PFI 1 input/output, A-4

phase, A-3

power requirements, A-5

safety, A-5

triggering, A-4 storing data in memory, 2-4 synchronizing multiple PXI devices, 2-8

NI 5620 User Manual I-2 ni.com

Index

system integration, by National

Instruments, B-1

System Reference Clock, PXI, 2-9

technical support resources, B-1 to B-2 TIO (timing engine), 2-6 trigger and clock routing area, 2-6 triggering

digital trigger sources (figure), 2-7 overview, 2-7 specifications, A-4

voltage, maximum working, A-5 voltage controlled crystal oscillator

(VCXO), 2-6

Web support from National Instruments, B-1 Worldwide technical support, B-2

National Instruments NI 5620 User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

NI 5620 User Manual

Support

Worldwide Technical Support and Product Information

National Instruments Corporate Headquarters

Worldwide Offices

Important Information

Warranty

Copyright

Trademarks

WARNING REGARDING USE OF NATIONAL INSTRUMENTS PRODUCTS

Compliance

Conventions

Contents

Installing the Software and Hardware

Safety Information

How the NI 5620 Works

Figure 2-1. Basic Signal Flow

Connecting Signals

Figure 2-2. NI 5620 Front Panel

Conditioning the Signal—Impedance, Dither, Gain, and AC Coupling

Input Impedance

Dither

Digitizing the Signal—The ADC

Incorporating the DDC

Storing Data in Memory

Block Diagram

Figure 2-3. Block Diagram

Other Features

Multiple-Record Acquisitions

Triggering

Figure 2-5. Digital Trigger Sources

Calibration

Synchronizing Multiple PXI Devices

Figure A-1. Frequency Response from 5 to 100 MHz

Glossary

Numbers/Symbols

Index