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NI 5412 Calibration Procedure

Introduction

This document contains instructions for calibrating the NI 5412 arbitrary waveform generator. 

This calibration procedure is intended for metrology labs. It describes specific programming 

steps for writing an external calibration procedure for the NI 5412.

Refer to 

ni.com/calibration

 for additional information about calibration solutions from 

National Instruments.

Software

Calibrating the NI 5412 requires installing NI-FGEN version 2.3 or later on the calibration 

system. You can download NI-FGEN from the National Instruments web site at 

ni.com/

updates

. NI-FGEN supports programming the 

Password

 and the 

External Calibration 

Procedures

 in the LabVIEW, LabWindows

/CVI

, and C application development 

environments (ADEs). When you install NI-FGEN, you need to install support only for the ADE 

that you intend to use.

NI-FGEN 2.3 or later includes all the functions and attributes necessary for calibrating the 

NI 5412. For LabWindows/CVI, the NI-FGEN function panel (

niFgen.fp

) provides help 

about the functions available. LabVIEW support is in the 

niFgen.llb

 file, and all calibration 

VIs appear in the Functions palette.

Calibration functions are C function calls or LabVIEW VIs in NI-FGEN. In this document, the 

C function call is shown first, followed by the corresponding LabVIEW VI or NI-FGEN 

LabVIEW property node, in parentheses. The C function calls are valid for any compiler capable 

of calling a 32-bit DLL. Many of the functions use constants defined in the 

niFgen.h

 file. 

To use these constants in C, you must include 

niFgen.h

 in your code when you write the 

calibration procedure. Refer to Table 1 for file locations.

 

Table 1.  

Calibration File Locations

File Name and Location

Description

IVI\Bin\niFgen_32.dll

The NI-FGEN library, which provides the 

functionality for calibrating the NI 5412.

IVI\Lib\msc\niFgen.lib
IVI\Lib\bc\niFgen.lib

Allows you to create applications that call 

functions in the 

niFgen_32.dll

:

• For Microsoft Visual C/C++, link to 

msc\niFgen.lib

• For LabWindows/CVI, link to the library 

appropriate to your current compatibility 

mode (

msc

 for Microsoft Visual C/C++).

IVI\Include\niFgen.h

A header file for the accessible functions in the 

niFgen_32.dll

. You must include this file in 

any C code that you write to call these functions.

Summary of Contents for 5412

Page 1: ...10 Calibration Procedures in LabWindows CVI 10 Calibration Procedures in C 10 Verifying NI 5412 Specifications 10 Verifying the Oscillator Frequency Accuracy 12 Verifying the DC Gain and Offset Accura...

Page 2: ...functions available LabVIEW support is in the niFgen llb file and all calibration VIs appear in the Functions palette Calibration functions are C function calls or LabVIEW VIs in NI FGEN In this docum...

Page 3: ...IVI Drivers niFgen niFgen fp CVI Contains the function panels for the functions in niFgen32 dll NI Signal Generators Getting Started Guide Contains NI FGEN installation hardware installation and hardw...

Page 4: ...ment External calibration requires different equipment for each applicable specification Refer to Table 2 for a list of equipment Table 2 Equipment Required for Calibrating the NI 5412 Instrument Appl...

Page 5: ...llator frequency and the calibration ADC are not adjusted during self calibration You can initiate self calibration interactively from Measurement Automation Explorer MAX or from the FGEN Soft Front P...

Page 6: ...form self calibration NI FGEN To self calibrate the NI 5412 programmatically using NI FGEN complete the following steps 1 Call niFgen_init niFgen Initialize VI to open an NI FGEN session using the fol...

Page 7: ...thin the calibration test limits the device is guaranteed to meet or exceed its published specifications for a full calibration interval two years For this reason you must verify against the calibrati...

Page 8: ...the published specifications during the first verification If all the output errors determined during the first verification fall within the calibration test limits the device is guaranteed to meet o...

Page 9: ...verify that the output error falls within the calibration test limits at the end of the calibration procedure Figure 2 shows the programming flow for the optional calibration Figure 2 Optional Calibra...

Page 10: ...Windows CVI To write calibration procedures in LabWindows CVI you must use the function panels included in the niFgen fp file After installation you can locate the calibration functions under the Cali...

Page 11: ...ogramming and cleaning up Note If any of these tests fail immediately after you perform an external adjustment verify that you have met the required test conditions before you return the NI 5412 to NI...

Page 12: ...eter receives the value that identifies the session created by this function This value acts as the session handle and is passed as the first parameter to all subsequent NI FGEN functions 3 Call niFge...

Page 13: ...array of waveform samples Each waveform should have 10 samples per cycle with a total of 500 samples and 50 sine wave cycles Because you set the sample rate to 100 MS s and because you are using 10 s...

Page 14: ...oltages and offsets measuring the voltage with a DMM and comparing the NI 5412 to the error limits The DC gain and offset accuracy verification procedure has two subprocedures that verify the followin...

Page 15: ...tributeViBoolean to enable the analog output niFgen property node Basic Operation Output Enabled using the following parameters vi The session handle returned from niFgen_init channelName 0 attributeI...

Page 16: ...tributeID NIFGEN_ATTR_ARB_OFFSET value 0 Repeat steps 12 through 22 for each of the 24 iterations listed in Table 4 changing the Gain value for each iteration Table 4 Values for Verifying the Gain of...

Page 17: ...00980 0 001700 14 0 205000 0 205000 0 205000 0 000828 0 001320 15 0 150000 0 150000 0 150000 0 000740 0 001100 16 0 105000 0 105000 0 105000 0 000668 0 000920 17 0 075000 0 075000 0 075000 0 000620 0...

Page 18: ...de Arbitrary Waveform Output Arbitrary Waveform Handle using the following parameters vi The session handle returned from niFgen_init channelName 0 attributeID NIFGEN_ATTR_ARB_WAVEFORM_HANDLE value Th...

Page 19: ...handle DC waveform niFgen property node Arbitrary Waveform Output Arbitrary Waveform Handle using the following parameters vi The session handle returned from niFgen_init channelName 0 attributeID NIF...

Page 20: ...0 075000 0 000763 0 001138 16 0 105000 0 052500 0 052500 0 000684 0 000946 17 0 075000 0 037500 0 037500 0 000631 0 000819 18 0 055000 0 027500 0 027500 0 000596 0 000734 19 0 037500 0 018750 0 018750...

Page 21: ...Test Limit listed in Table 5 9 Call niFgen_AbortGeneration niFgen Abort Generation VI to abort the waveform generation using the following parameter vi The session handle returned from niFgen_init 10...

Page 22: ...that you want to verify You can find this name under Devices and Interfaces in MAX IDQuery VI_TRUE resetDevice VI_TRUE vi A pointer to a ViSession The variable passed by reference through this parame...

Page 23: ...eate Waveform Data VI to the Waveform Data Array input of the niFgen Create Waveform DBL VI 8 Configure the DMM using the following settings Function AC voltage Range Refer to Table 6 Input impedance...

Page 24: ...264 0 004950 0 009192 12 0 415000 0 5 0 293449 0 003642 0 006576 13 0 300000 0 5 0 212132 0 002828 0 004950 14 0 205000 0 5 0 144957 0 0021587 0 003606 15 0 150000 0 5 0 106066 0 001768 0 002828 16 0...

Page 25: ...s of the NI 5412 using a power meter To verify the flatness of the NI 5412 complete the following steps 1 Connect the NI 5412 CH 0 front panel connector to the power meter using the required adapter 2...

Page 26: ...m samples double representation wfmHandle A pointer to a waveform The variable passed by reference through this parameter acts as a handle to the waveform and can be used for setting the active wavefo...

Page 27: ...e power meter to stabilize for 10 seconds 14 Measure and record the reference 50 kHz power Wref of the positive output in Watts 15 Configure the NI 5412 and power meter frequency according to the next...

Page 28: ...brate You can find this name under Devices and Interfaces in MAX password The password required to open an external calibration session If this password has not been changed since manufacturing the pa...

Page 29: ...4 NI 5412 External Calibration Procedure Initializing the External Calibration Session Call niFgen_InitExtCal niFgen Init Ext Cal VI to open an NI FGEN external calibration session using the followin...

Page 30: ...tput Calibration VI using the following parameter vi The session handle returned from niFgen_InitExtCal 2 Call niFgen_WriteBinary16AnalogStaticValue niFgen Write Binary 16 Analog Static Value VI to se...

Page 31: ...y node Basic Operation Output Impedance using the following parameters vi The session handle returned from niFgen_InitExtCal channelName 0 attributeID NIFGEN_ATTR_OUTPUT_IMPEDANCE value 50 9 Call niFg...

Page 32: ...libration Pre Amplifier Attenuation using the following parameters vi The session handle returned from niFgen_InitExtCal channelName 0 attributeID NIFGEN_ATTR_PRE_AMPLIFIER_ATTENUATION value The Pre A...

Page 33: ...eturned from niFgen_InitExtCal channelName 0 attributeID NIFGEN_ATTR_GAIN_DAC_VALUE value 1000 g Call niFgen_Commit niFgen Commit VI to commit the attribute values to the device using the following pa...

Page 34: ...d in the order that you measured them Adjusting the Main Path Pre Amplifier Gain 1 Call niFgen_SetAttributeViInt32 to set the analog path value niFgen property node Output Attributes Analog Path using...

Page 35: ...vi The session handle returned from niFgen_InitExtCal channelName 0 attributeID NIFGEN_ATTR_GAIN_DAC_VALUE value 1500 b Call niFgen_WriteBinary16AnalogStaticValue niFgen Write Binary 16 Analog Static...

Page 36: ...alAdjustMainPathPreAmpGain niFgen Cal Adjust Main Path Pre Amp Gain VI using the following parameters vi The session handle returned from niFgen_InitExtCal channelName 0 configuration The Current Conf...

Page 37: ...rrent Configuration values for each iteration Table 10 Attributes and Values for the Main Path Post Amplifier Gain and Offset Iteration Analog Path Post Amp Attenuation Current Configuration 1 NIFGEN_...

Page 38: ...niFgen property node Calibration Offset DAC Value using the following parameters vi The session handle returned from niFgen_InitExtCal channelName 0 attributeID NIFGEN_ATTR_OFFSET_DAC_VALUE value 5000...

Page 39: ...ncy passing the measured value to NI FGEN so that the oscillator can be adjusted and then remeasuring the resulting frequency This process is repeated until the difference between the desired and meas...

Page 40: ...the following parameters vi The session handle returned from niFgen_InitExtCal channelName 0 attributeID NIFGEN_ATTR_DIGITAL_FILTER_INTERPOLATION_FACTOR value 4 7 Call niFgen_SetAttributeViReal64 to...

Page 41: ...e generated waveform This value is the Measured Frequency which is used in step 14 14 Repeat steps 14a through 14d for as long as the difference between the Measured Frequency and the desired frequenc...

Page 42: ...ll niFgen_SetAttributeViInt32 to set the analog path value niFgen property node Output Attributes Analog Path using the following parameters vi The session handle returned from niFgen_InitExtCal chann...

Page 43: ...ration Output Enabled using the following parameters vi The session handle returned from niFgen_InitExtCal channelName 0 attributeID NIFGEN_ATTR_OUTPUT_ENABLED value VI_TRUE 10 Call niFgen_Commit niFg...

Page 44: ...ssed by reference through this parameter receives the voltage measured by the onboard ADC This value is cal ADC measurement 0 which is used in step 31 18 Call niFgen_SetAttributeViBoolean to enable th...

Page 45: ...tep 31 27 Call niFgen_SetAttributeViBoolean to enable the analog output niFgen property node Basic Operation Output Enabled using the following parameters vi The session handle returned from niFgen_In...

Page 46: ...owing parameter vi The session handle returned from niFgen_InitExtCal Closing the External Adjustment Session When you have completed all the adjustment stages you must close the external adjustment s...

Page 47: ...re for both external and self calibration FGEN SFP To retrieve data using the FGEN SFP complete the following steps 1 Launch the FGEN SFP 2 Select the device from which you want to retrieve informatio...

Page 48: ...is your complete resource for technical support At ni com support you have access to everything from troubleshooting and application development self help resources to email and phone assistance from...

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