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CALIBRATION PROCEDURE

NI PXI-5404 

This document contains step-by-step instructions for writing a calibration procedure for the 
NI PXI-5404 100 MHz Frequency Source.

Contents

Calibration Overview ............................................................................................................... 2

What Is External Calibration? .......................................................................................... 2
Why Should You Calibrate?............................................................................................. 2
How Often Should You Calibrate?................................................................................... 2

Equipment and Other Test Requirements................................................................................. 2

Test Equipment................................................................................................................. 2
Test Conditions................................................................................................................. 4
Documentation.................................................................................................................. 4
Software............................................................................................................................ 4

Writing Your Calibration Procedure ........................................................................ 4
Calibration Software................................................................................................. 4
Calibration Procedures in C...................................................................................... 6
Calibration Procedures in LabVIEW........................................................................ 6
Calibration Procedures in Visual Basic .................................................................... 6

Verification............................................................................................................................... 7

Verifying Frequency Accuracy ........................................................................................ 8
Verifying SINE Out Amplitude Accuracy ....................................................................... 9
Verifying SINE Out Amplitude Passband Flatness.......................................................... 10
Verifying CLOCK Out Duty Cycle Accuracy ................................................................. 13

External Adjustment ................................................................................................................. 14

Overview of Calibration Constants .................................................................................. 14

VCXO DAC ............................................................................................................. 14
GAIN DAC............................................................................................................... 15
SYNC DAC .............................................................................................................. 15

Setting Up and Configuring the NI 5404.......................................................................... 15
Adjusting the NI 5404 ...................................................................................................... 16

Adjusting the VCXO DAC for Frequency Accuracy............................................... 17
Adjusting the SINE Out Amplitude.......................................................................... 20
Adjusting the CLOCK Out Duty Cycle.................................................................... 25

Closing the Calibration Session........................................................................................ 28

Calibration Function Reference................................................................................................ 28
Where to Go for Support .......................................................................................................... 48

Summary of Contents for NI PXI-5404

Page 1: ...on Procedures in C 6 Calibration Procedures in LabVIEW 6 Calibration Procedures in Visual Basic 6 Verification 7 Verifying Frequency Accuracy 8 Verifying SINE Out Amplitude Accuracy 9 Verifying SINE O...

Page 2: ...g the calibration constants and storing the new calibration constants in the onboard EEPROM The host computer reads the calibration constants and the software uses them to compensate for errors and to...

Page 3: ...requency Counter Frequency accuracy Bandwidth 150 MHz Frequency accuracy to 500 ppb NI PXI 5660 Agilent HP 8560E Agilent HP 53131A or HP 53132A with timebase option 001 010 or 012 Rohde Schwarz FSU26...

Page 4: ...the NI 5404 Writing Your Calibration Procedure The calibration process is described in the External Adjustment section including step by step instructions on calling the appropriate calibration functi...

Page 5: ...unctionality for calibrating your module VXIpnp WinNT Win95 lib msc niArbCal lib VXIpnp WinNT Win95 lib bc niArbCal lib A lib file that allows you to create applications that call functions in the niA...

Page 6: ...isual Basic complete the following steps 1 Configure the project to reference the niArbCal dll by selecting Project References from the menu bar 2 Click Browse and navigate to your system directory 3...

Page 7: ...he NI 5404 module The following steps describe the code you use to generate the appropriate signals as well as the NI FGEN function calls you make to verify specifications The code varies depending on...

Page 8: ...spectrum analyzer using an SMB to SMA cable Generate a 10 MHz frequency using the NI 5404 module by completing the following steps 1 Call niFgen_init to initialize the module you are testing and to c...

Page 9: ...s error when comparing the measured frequency to the frequency accuracy listed in the Specifications for the NI PXI 5404 5 Call niFgen_close to close the module I O session destroy the instrument driv...

Page 10: ...voltage and account for this error when comparing the measured voltage to the amplitude accuracy listed in the Specifications for the NI PXI 5404 Note A 4 Vpk pk sine wave has an rms amplitude of 1 4...

Page 11: ...itude measurements at frequency indices 0 11 which are relative to the absolute amplitude measurement made by the DMM at frequency index 0 The latter choice is preferred To measure the SINE out amplit...

Page 12: ...FGEN_VAL_WFM_SINE b Measure the SINE out amplitude using a power meter specified in Table 1 To determine if the measured amplitude is within the specification of the NI 5404 you must determine the mea...

Page 13: ...vice True 2 Call niFgen_ConfigureStandardWaveform to select the channel to output a waveform Set the following parameters vi The output value sessionHandle you obtained from the niFgen_init function C...

Page 14: ...e oscilloscope that you used to measure the duty cycle and account for this error when comparing the measured duty cycle to the duty cycle accuracy listed in the Specifications for the NI PXI 5404 8 C...

Page 15: ...l frequencies Setting Up and Configuring the NI 5404 To set up and configure the NI 5404 module for adjustment complete the following steps 1 Install the NI 5404 module in the PXI chassis 2 Configure...

Page 16: ...brate theVCXO DAC for Frequency Accuracy Calibrate the GAIN DAC for Sine Amplitude Accuracy and Passband Flatness Accuracy Apply Session Constants niHSSources_ApplySessionConstants Calibrate the SYNC...

Page 17: ...ness accuracy as described in the Adjusting the CLOCK Out Duty Cycle section 4 Call niHSSources_CalEnd niHSSources Cal CalEnd VI to close the session using the following parameters sessionHandle A poi...

Page 18: ...cess Figure 3 VCXO Adjustment Process Generate a Waveform at the Desired Frequency Call niHSSources_CalibrateVCXO Initialize VCXO Calibration Measure Frequency Call niHSSources_CalAdjust with Measured...

Page 19: ...SET_VCXO 4 Repeat steps 4a 4c 16 times to adjust the frequency accuracy a Call niHSSources_CalibrateVCXO niHSSources Cal CalibrateVCXO VI to program the adjusted VCXO DAC value to the hardware Set the...

Page 20: ...this value to the hardware when you call niHSSources_CalibrateAmplitude niHSSources Cal CalibrateAmplitude VI When the program calls niHSSources_CalAdjust niHSSources Cal CalAdjust VI this variable i...

Page 21: ...urces_CalibrateAmplitude Initialize SINE AmplitudeCalibration Measure SINE Out Amplitude Call niHSSources_CalAdjust with Measured Amplitude SINE Out Amplitude Adjustment Call niHSSources_ApplySessionC...

Page 22: ...ibration constants to the underlying driver This function ensures that the session uses the new VXCO DAC values calculated during the VCXO calibration Table 5 SINE Out Calibration Frequencies Index Fr...

Page 23: ...surement because the power meter has a 50 input impedance The result of the subtraction is the power level of the 50 kHz SINE out into a 50 load c Measure the 50 kHz amplitude with the power meter and...

Page 24: ...5 repeat the following steps eight times a Call niHSSources_CalibrateAmplitude niHSSources Cal CalibrateAmplitude VI to program the adjusted GAIN DAC value to the hardware Set the following parameter...

Page 25: ...stments for every frequency Close the Calibration Session by Calling niHSSources_CalEnd Call niHSSources_ApplySessionConstants SINE Out Amplitude Adjustment Generate a Waveform at the Current Frequenc...

Page 26: ...VI to instruct the driver to use data from previous calibration steps of the session This function ensures that the driver uses the values calculated during the VCXO and SINE out amplitude calibration...

Page 27: ...ents The number of duty cycle measurements taken and passed into the niHSSources_CalAdjust function niHSSources Cal CalAdjust VI d For each SYNC DAC value in Table 6 for the frequency index complete t...

Page 28: ...iHSSources Cal CalEnd VI to save the new constants Set the following parameters sessionHandle The handle of the calibration session for the module action niHSSources_COMMIT_CONSTANTS Calibration Funct...

Page 29: ...dle Purpose Initiates a calibration session for the specified module Parameters Name Description device A number corresponding to the DAQ device number of the module to be calibrated password The exte...

Page 30: ...he values of the measured and actual data Parameters Name Description sessionHandle The handle of the calibration session for the module created by calling niHSSources_CalStart measurementMode The cal...

Page 31: ...se Closes the calibration session and either commits or discards the new constants that have been calculated Parameters Name Description sessionHandle A pointer to the handle of the calibration sessio...

Page 32: ...ate of the last calibration either from the internal self calibration or external manual calibration area Parameters Name Description device A number corresponding to the DAQ device number of the modu...

Page 33: ...long device long area long count Purpose Retrieves the number of times the module has been calibrated either internally self calibration or externally manual calibration Parameters Name Description de...

Page 34: ...cInfo unsigned long device char miscInfo Purpose Retrieves four bytes of data from the external adjustment miscellaneous data area Parameters Name Description device A number corresponding to the DAQ...

Page 35: ...alStoreMiscInfo unsigned long device char miscInfo Purpose Stores four bytes of data in the external adjustment miscellaneous data area Parameters Name Description device A number corresponding to the...

Page 36: ...l niHSSources_CalChangePassword unsigned long device char oldPassword char newPassword Purpose Changes the password Parameters Name Description device A number corresponding to the DAQ device number o...

Page 37: ...ype __declspec dllexport long __stdcall niHSSources_DeviceReset unsigned long sessionHandle Purpose Resets the NI 54XX module and puts it in a default reset state Parameter Name Description sessionHan...

Page 38: ...t unsigned long sessionHandle unsigned long outputState Purpose Enables or disables the output of the module Parameters Name Description sessionHandle The handle of the calibration session for the mod...

Page 39: ...Purpose Causes the module to output a sine wave with a specified amplitude and frequency Parameters Name Description sessionHandle The handle of the calibration session for the module created by call...

Page 40: ...onHandle unsigned long type Purpose The VCXO is calibrated iteratively Call this function before calibrating the VCXO because it sets many internal variables to appropriate values for the VCXO calibra...

Page 41: ...the current test value Use this function during calibration to iteratively converge on the best value A new value is calculated then this function is called to set the VCXO then the output is measured...

Page 42: ..._CalGetLastCalibrationTemperature unsigned long device int area double temperature Purpose Retrieves the temperature at which the module was last calibrated Parameters Name Description device A number...

Page 43: ...d based on calibration steps performed during the session This function commits the session constants to the underlying driver so that the module is calibrated according to the newly updated constants...

Page 44: ...e SINE out amplitude of the NI 5404 is calibrated iteratively Call this function before calibrating the sine amplitude because it sets many internal variables to appropriate values for the calibration...

Page 45: ...long sessionHandle Purpose Returns the sine amplitude with the current test value Use this function during calibration to iteratively converge on the best value A new value is calculated then output i...

Page 46: ...librating the duty cycle of the CLOCK out because it sets many internal variables to appropriate values for the calibration Parameters Name Description sessionHandle A handle to the calibration sessio...

Page 47: ...ed long DACValue Purpose Sets the SYNC calibration DAC to the specified value This value affects the duty cycle of the signal at the CLOCK out and is used during a duty cycle calibration Parameters Na...

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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