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157

 

Keysight 4000 X-Series Oscilloscopes 

Advanced Training Guide

B Oscilloscope Bandwidth 

Tutorial

Defining Oscilloscope Bandwidth / 158
Required Bandwidth for Analog Applications / 159
Required Bandwidth for Digital Applications / 160
Digital Clock Measurement Comparisons / 163

Oscilloscopes have many different specifications that determine the accuracy that 

signals can be captured and measured. But the primary specification of an 

oscilloscope is its bandwidth. This tutorial on oscilloscope bandwidth will provide 

you some helpful hints on how to select an oscilloscope with the appropriate 

bandwidth for your digital and analog applications. But first, let’s define 

oscilloscope bandwidth.

Содержание 4000 X-Series

Страница 1: ...b guide and tutorial for making advanced oscilloscope measurements using an Keysight 4000 X Series oscilloscope with the DSOXEDK training kit Keysight 4000 X Series Oscilloscopes Advanced Training Gui...

Страница 2: ...described in this document are furnished under a license and may be used or copied only in accor dance with the terms of such license Restricted Rights Legend If software is for use in the performanc...

Страница 3: ...vanced Triggering Search Navigation and Segmented Acquisition Labs Lab 7 Triggering on a Digital Burst using Trigger Holdoff 44 Lab 8 Triggering on Unique Pulses and Glitches using Pulse width Trigger...

Страница 4: ...Decoding Triggering and Searching on ARINC 429 Signals 139 Lab 24 Decoding Triggering and Searching on MIL STD 1553 Signals 144 A Oscilloscope Block Diagram and Theory of Operation DSO Block Diagram...

Страница 5: ...5 Keysight 4000 X Series Oscilloscopes Advanced Training Guide 1 Getting Started Lab Guide At a Glance 6 Front Panel Overview 8...

Страница 6: ...robed by simply connecting a standard 10 1 passive probe between channel 1 s input BNC and the front panel terminal labeled Demo 1 and another probe between channel 2 s input BNC and the terminal labe...

Страница 7: ...ages and then begin with Chapter 2 Oscilloscope Familiarization Labs starting on page 13 Once you have become familiar with using the basic functions of the oscilloscope you can then skip to particula...

Страница 8: ...variety of people it is a good measurement procedure to put the oscilloscope in a known starting mode Default Setup This makes it easy to duplicate measurements because no special conditions are set T...

Страница 9: ...rve the changes in the displayed signal The current timebase setting is displayed at the top of the display on the status line b Turn the small knob in the horizontal control section to move the trigg...

Страница 10: ...ain to turn the channel on and off Turn the small knobs to control the vertical offset position of the waveform moving the ground level up or down Trigger Controls Turn the Trigger Level knob to move...

Страница 11: ...Press and hold the Mode softkey to read the built in help about the Auto and Normal trigger modes Tools Controls Press the Utility key to access the I O ports file explorer options service information...

Страница 12: ...12 4000 X Series Oscilloscopes Advanced Training Guide 1 Getting Started...

Страница 13: ...liarization Labs Lab 1 Using Cursors and Automatic Parametric Measurements 14 Lab 2 Using Zoom Display to Perform Gated Measurements 21 Lab 3 Using Waveform Math 25 Lab 4 Using Peak Detect Acquisition...

Страница 14: ...the channel 1 probe to the Demo 1 terminal and ground 2 Press Default Setup on the scope s front panel 3 Press Help then press the Training Signals softkey 4 Using the touch screen Training Signals me...

Страница 15: ...ulse width and peak to peak voltage of this waveform First visually locate the Cursors button in the Measure section of the front panel as shown in Figure 2 9 Push the Cursors button then select X1 on...

Страница 16: ...e tracking cursor mode you have the ability to control the time placement of the cursors and then the scope will automatically position the voltage cursors on the waveform where the time cursors inter...

Страница 17: ...Figure 4 showing four continuously update measurements Frequency Vp p Vmax and Vmin Let s now perform four different measurements 18 Set the scope s timebase to 200 0 ns div Expanding on the pulse wil...

Страница 18: ...eform after the overshoot and ringing have settled Likewise Vbase is the steady state low level of the waveform For digital pulse parameter measurements Vtop and Vbase are often more important paramet...

Страница 19: ...ust above the power switch 25 Press the Back key again because we descended two levels into this menu 26 Press the Rise measurement on the right of the display select Track with Cursors Using these us...

Страница 20: ...add this set of measurements The Snapshot All measurement provides us with a one time snapshot measurement of several parameters in order to completely characterize our input signal as shown in Figure...

Страница 21: ...rminal and ground 2 Press the Default Setup key on the scope s front panel 3 Press Help then press the Training Signals softkey 4 Select the Digital Burst with Infrequent Glitch signal then press the...

Страница 22: ...Figure 8 Let s now turn on a Width measurement 11 Press the Meas front panel key next to the Cursors knob 12 Press the Clear Meas softkey then press the Clear All softkey 13 Press the Type softkey the...

Страница 23: ...know the widths of the 2nd 3rd 4th etc pulses 15 Press the button in the Horizontal section of the front panel to turn on the scope s zoom display mode 16 Set the Zoom timebase to 50 00 ns div by turn...

Страница 24: ...see on your scope s display an expansion of just the 3rd pulse in this burst in the lower portion of the display as should in Figure 10 And the Width measurement should be measuring the positive pulse...

Страница 25: ...of the component is connected to ground In this case you could capture waveforms at both ends of the component relative to ground and then subtract one waveform from the other Let s try it 1 Connect t...

Страница 26: ...panel key the press the Training Signals softkey 13 Press the Phase softkey then turn the Entry knob to vary the phase shift You can also tap the angle value to set it yourself When the phase shift is...

Страница 27: ...MHz You should now see a display similar to Figure 12 The scope is now displaying both a time domain waveform Voltage versus Time as well as a frequency domain waveform Power in units of dB versus Fr...

Страница 28: ...e 2nd highest frequency peak The frequencies at the X1 and X2 cursor locations are displayed near the bottom of the scope s display Let s now verify the fundamental frequency of this signal using the...

Страница 29: ...uce its sampling rate in order to fill the required waveform time All DSOs and MSOs do this For example let s assume that you want to capture a relatively slow signal and need to set the scope s timeb...

Страница 30: ...t logo on the scope s display and the scope is now intermittently capturing the narrow glitches The scope is under sampling the narrow glitches Sometimes the scope captures a single point on the peak...

Страница 31: ...scope would analyze a group of 200 consecutive samples in real time sampled at a high rate and then store just the maximum and minimum digitized values for this group of 200 points which is just 2 poi...

Страница 32: ...g Guide 2 Oscilloscope Familiarization Labs To learn more about oscilloscope real time sampling refer to Keysight s Application Note titled Evaluating Oscilloscope Sample Rates vs Sampling Fidelity li...

Страница 33: ...mented Memory acquisition mode is another solution to optimize memory depth and sample rate especially when attempting to capture multiple low duty cycle type signals Keysight 4000 X Series Oscillosco...

Страница 34: ...ation Labs You should see a single burst of sine waves similar to what is shown in Figure 15 Let s now rescale the timebase in an attempt to capture several of these bursts 9 Set the scope s timebase...

Страница 35: ...n in Figure 16 Again this is because the scope automatically reduced its sample rate in order to capture a longer time span with its limited amount of acquisition memory Let s now zoom in and take a c...

Страница 36: ...eform would still be under sampled after zooming in on a stored trace Another solution would be to purchase a scope with much deeper memory Let s now use the scope s Segmented Memory acquisition mode...

Страница 37: ...ith a time of day stamp as shown in Figure 18 The captured waveform should also have very high resolution because the scope used a high sample rate to capture each waveform If you attempted to capture...

Страница 38: ...Guide 2 Oscilloscope Familiarization Labs useful tool for capturing multiple serial packets of digital data which will be demonstrated in Chapter 4 Serial Bus Decoding Triggering Search Navigation an...

Страница 39: ...occurrences of this particular glitch To enable Mask Testing your oscilloscope must have the mask test option installed Option DSOX4MASK You can verify the installed options on your oscilloscope at H...

Страница 40: ...at we are triggering on Because this scope can update waveforms as fast as 1 000 000 waveforms sec the scope can capture the glitch on average once per second Let s now use the scope s Mask Test capab...

Страница 41: ...ee or fewer defects per million tested Because this particular glitch occurs 1 1 000 000 we have a Sigma quality factor that exceeds 6 Let s now set up the oscilloscope to stop on the first detected f...

Страница 42: ...lection you can also set up mask testing to run for a specific number of tests minimum time or minimum Sigma test criteria Note that in addition to creating a pass fail mask using the auto mask creati...

Страница 43: ...d Glitches using Pulse width Trigger 48 Lab 9 Triggering on the Nth Pulse within a Burst using Nth Edge Burst Trigger 53 Lab 10 Triggering on and Searching for Edge Speed Violations 55 Lab 11 Triggeri...

Страница 44: ...n order to trigger on a burst of digital pulses 1 Connect the channel 1 probe to the Demo 1 terminal and ground 2 Press Default Setup on the scope s front panel 3 Press Help then tap the Training Sign...

Страница 45: ...ns so that we can see a single shot acquisition of the bursts and then make some measurements We will then use these measurements to enter a specific trigger holdoff time in order to synchronize trigg...

Страница 46: ...hat it always triggers on just the 1st edge of each burst rather than a random edge We can do this using the scope s trigger holdoff capability With trigger holdoff we can instruct the scope to always...

Страница 47: ...ggers on the 1st edge of a burst of pulses center screen and then disables triggering for 45 00 s holdoff time During this holdoff time the scope ignores the 2nd 3rd 4th etc crossings and then re arms...

Страница 48: ...glitch 1 Connect the channel 1 probe to the Demo 1 terminal and ground 2 Press Default Setup on the scope s front panel 3 Press Help then press the Training Signals softkey 4 Tap the Digital Burst wi...

Страница 49: ...triggering mode assuming that the input signal is a repetitive burst We will show how to use the Nth Edge Burst triggering mode in the next lab Lab 9 Another option would be to use the scope s Pulse W...

Страница 50: ...hat this pulse has an approximate width of 300 ns Now take note of the narrow infrequent glitch that occurs after the end of this burst of six pulses In addition to using the scope s Pulse Width trigg...

Страница 51: ...occurrence of each burst But before beginning a Segmented Memory acquisition we will change the trigger condition to trigger on the 300 ns wide pulse again so that we can capture every occurrence of t...

Страница 52: ...ctively captured 500 consecutive occurrences of this burst for a total acquisition time of than 40 ms as shown in Figure 28 The scope did not waste valuable acquisition memory capturing signal idle ti...

Страница 53: ...previous lab 1 Connect the channel 1 probe to the Demo 1 terminal and ground 2 Press Default Setup on the scope s front panel 3 Press Help then press the Training Signals softkey 4 Open the Training...

Страница 54: ...front panel key then tap Nth Edge Burst using the Trigger Type menu 10 Tap the Idle softkey then set the minimum signal idle time to 2 00 s 11 Tap the Edge softkey then set the edge count to 3 Your s...

Страница 55: ...e speed violations as well as using the scope s Segmented Memory acquisition to capture multiple and consecutive occurrences of edge speed violations 1 Connect the channel 1 probe to the Demo 1 termin...

Страница 56: ...r This is because the slower transitioning edges occur less often than the faster transitioning edges Perhaps these slower transitioning edges are in violation of meeting minimum required specificatio...

Страница 57: ...ight help us isolate what the root cause might be that is causing these occasional violations Uniquely triggering on edge speed violation signals can be accomplished on Keysight s 4000 X Series oscill...

Страница 58: ...Fall Time violation edges the Keysight 4000 X Series oscilloscopes can also perform Search Navigation to find multiple edge speed violation conditions regardless of the specific trigger setup conditio...

Страница 59: ...ress the zoom front panel key 25 Press the and navigation keys to navigate to each discovered edge violation Let s now use the scope s Segmented Memory mode of acquisition to capture 500 consecutive o...

Страница 60: ...review all 500 captured segments 33 Set the Current Segment to 500 and note the time tag of the last captured segment Segmented Memory optimizes oscilloscope acquisition memory by only capturing impor...

Страница 61: ...capability to automatically find mark and then navigate to runt pulses as well as use the scope s segmented memory acquisition to capture multiple and consecutive occurrences of runt conditions 1 Con...

Страница 62: ...tive runts pulses that fail to meet a minimum low level Let s now set up the scope to trigger on just positive runt conditions 9 Press the Trigger front panel key and select Runt type triggering 10 Ta...

Страница 63: ...negative runts only or either polarity runts using the appropriate softkey selection Note that the Keysight 4000 X Series oscilloscopes can also trigger on runt pulses that meet a specific time quali...

Страница 64: ...pes can also perform Search Navigation to find multiple runt pulse conditions regardless of the specific trigger setup condition Let s now capture a longer stream of pulses and perform an automatic se...

Страница 65: ...each discovered positive runt pulse Let s now use the scope s Segmented Memory mode of acquisition to capture 500 consecutive occurrences of runt pulses of either polarity and with no specific time qu...

Страница 66: ...ry acquisition 32 Tap the Current Segment softkey then turn the Entry knob to review all 500 captured segments 33 Set the Current Segment to 500 and note the time tag of the last captured segment Segm...

Страница 67: ...und 3 Press Default Setup on the scope s front panel 4 Press Help then tap the Training Signals softkey 5 Using the Entry knob select the Setup Hold Violation Signals signal then press the Output soft...

Страница 68: ...rom the rising falling edges of the data signal to the rising edge of the clock signal If you make this measurement based on the brighter green traces then you should measure a setup time in the range...

Страница 69: ...ory mode of acquisition to capture 500 consecutive occurrences of a setup time violation But to complete the rest of this lab your scope must be licensed with the Segmented Memory option 10 Press the...

Страница 70: ...important segments of a waveform based on the trigger condition and timebase setting In this example we have selectively captured 500 consecutive occurrences of a setup time violation for a total acqu...

Страница 71: ...ndition by both time and event count of an edge of any channel 1 Connect the channel 1 probe to the Demo 1 terminal and ground 2 Connect the channel 2 probe to the Demo 2 terminal and ground 3 Press D...

Страница 72: ...one of the wider digital pulses on channel 2 To do this we will qualify triggering on the channel 1 pulse then delay arming of the trigger past the 5 MHz analog burst and then finally trigger on the...

Страница 73: ...e 73 Your scope s triggering should now be synchronized on the 3rd digital pulse on channel 2 after qualifying on the channel 1 pulse and after delaying past the higher frequency analog burst as shown...

Страница 74: ...en upgraded with the MSO option Option MSO You can verify the installed options on your oscilloscope at Help About Oscilloscope 1 Connect the channel 1 probe to the Demo 1 terminal and ground 2 Press...

Страница 75: ...ope D7 D0 bypassing the parallel logic probe In a real measurement application such as this you would use the logic probe that is supplied with the scope to probe signals such as these The scope is cu...

Страница 76: ...should now be triggering on logic pattern 1110 0110 D7 D0 and the top of the sine wave should be centered on screen as shown in Figure 47 In addition to displaying individual digital channels this sc...

Страница 77: ...ify to trigger on a pattern condition as a HEX value The HEX value of the input to the DAC when the output is at its lowest amplitude is 1AHEX Let s now specify to trigger on 1AHEX 19 Press the Trigge...

Страница 78: ...ining Guide 3 Advanced Triggering Search Navigation and Segmented Acquisition Labs Your scope should now be triggering on 1AHEX which is coincident with the lowest output level of DAC as shown in Figu...

Страница 79: ...32 UART Serial Bus Signals 94 Lab 18 Decoding Triggering and Searching on CAN Serial Bus Signals 102 Lab 19 Decoding Triggering and Searching on LIN Serial Bus Signals 110 Lab 20 Decoding Triggering a...

Страница 80: ...on the I2 C protocol and signaling To complete this lab your scope must be licensed with the I2 C trigger and decode option Option EMBD You can verify the installed options on your oscilloscope at Hel...

Страница 81: ...ial data signal SDA Let s first set up the scope to intelligently decode this data stream based on the I2C protocol and then we will establish a more unique trigger point using I2 C triggering 12 Pres...

Страница 82: ...e MSB of the address byte and symbolically decodes it as to whether the address byte is a Read or Write instruction So the typical address decoding format most engineers prefer is the 7 bit format whi...

Страница 83: ...A following by a data byte equal to either 80 or C0 without an acknowledge A Let s now capture a very long stream of I2 C data and then manually search through the captured and decoded record 22 Set...

Страница 84: ...Edge softkey then select Serial 1 I2C 30 Tap the Search for softkey then select Missing Acknowledge as our search criteria The white triangles near the top of the waveform area mark the time location...

Страница 85: ...b to re position the trigger point back to center screen 32 Set the scope s timebase to 100 0 s div 33 Press the Run Stop front panel key to begin repetitive acquisitions again 34 Press the Acquire fr...

Страница 86: ...cope acquisition memory by only capturing important segments of a waveform based on the trigger condition and timebase setting In this example we have selectively captured approximately 20 seconds of...

Страница 87: ...omplete this lab your scope must be licensed with the SPI trigger and decode option Option EMBD as well as the MSO option You can verify the installed options on your oscilloscope at Help About Oscill...

Страница 88: ...SI data signal Master out Slave in and D8 is the MISO data signal Master in Slave out You can also think of these signals as serial data out and serial data in relative to the Master D7 is the SPI clo...

Страница 89: ...labels Your scope should now be decoding the MOSI and MISO serial data lines similar to Figure 56 However the scope is not yet triggering on these signals The scope should be randomly auto triggering...

Страница 90: ...tured and decoded record 30 Press the Serial front panel key 31 Tap the Lister softkey then set the Window menu to select Half Screen 32 Set the scope s timebase to 20 00 ms div 33 Press Run Stop to s...

Страница 91: ...the Search front panel key 38 Tap the Search Edge softkey then select Serial 1 SPI 39 Tap the Bits softkey 40 Tap the Select Digit softkey then select the upper nibble Digit 0 41 Tap the Hex softkey...

Страница 92: ...rences of SPI serial bus traffic when MOSI 03HEX But to complete the rest of this lab your scope must be licensed with the Segmented Memory option 44 Push the horizontal position delay knob to re posi...

Страница 93: ...mportant segments of a waveform based on the trigger condition and timebase setting In this example we have selectively captured over 4 seconds of total acquisition time as shown in Figure 59 Note tha...

Страница 94: ...ensed with the RS232 UART trigger and decode option Option COMP You can verify the installed options on your oscilloscope at Help About Oscilloscope 1 Connect the channel 1 probe to the Demo 1 termina...

Страница 95: ...aptured by channel 2 is an RS232 serial transmit data signal TX Let s first set up the scope to intelligently decode this data stream based on the RS232 UART protocol and then we will establish a more...

Страница 96: ...should now see RS232 UART decoding of these signals on your scope s display similar to Figure 61 but we still haven t established stable triggering The scope is still triggering on any rising edge of...

Страница 97: ...the Entry knob to scroll through the decoded data As you scroll through the data note that waveforms track This means that the frame that the arrow points to in the lister table corresponds to the wav...

Страница 98: ...eration as shown in Figure 63 These frames are also marked in orange in the first pointer column of the lister table Your scope should have found and marked 4 or 5 occurrences of this search operation...

Страница 99: ...he trigger level knob 41 Tap the Mode Auto softkey then select Normal The parity error is infrequent so the scope will auto trigger on an asynchronous interval unless we force the normal mode of trigg...

Страница 100: ...y by only capturing important segments of a waveform based on the trigger condition and timebase setting In this example we have selectively captured just bursts of data that include a parity error ov...

Страница 101: ...ng Triggering Search Navigation and Segmented Acquisition Labs 4 4000 X Series Oscilloscopes Advanced Training Guide 101 Figure 66 Decoded RS232 UART message indicating which oscilloscope vendor is 1...

Страница 102: ...utorial on the CAN protocol and signaling To complete this lab your scope must be licensed with the CAN LIN trigger and decode option Option AUTO You can verify the installed options on your oscillosc...

Страница 103: ...er point using simple edge triggering This signal is a packet frame of CAN serial bus traffic Let s first set up the scope to intelligently decode this data stream based on the CAN protocol and then w...

Страница 104: ...ring The scope is still triggering on any rising edge of channel 1 default trigger condition Let s now set up the scope to trigger on a CAN data frame with the ID 07FHEX 13 Press the Trigger front pan...

Страница 105: ...front panel key 19 Tap the Lister softkey then use the Window menu to select Half Screen 20 Set the scope s timebase to 100 00 ms div 21 Press Run Stop to stop repetitive acquisitions 22 Tap the Scro...

Страница 106: ...Serial 1 CAN 27 Tap the Search for softkey then select All Errors The white triangles near the top of the waveform area mark the time location of each found occurrence of our search operation as shown...

Страница 107: ...top front panel to begin repetitive acquisition again 31 Press the Trigger front panel key 32 Tap the Trigger ID RTR softkey then select All Errors 33 Press the Mode Coupling key in the Trigger sectio...

Страница 108: ...ion and timebase setting In this example we have selectively captured approximately 10 seconds of total acquisition time as shown in Figure 71 Note that we can also view the segmented decoded CAN seri...

Страница 109: ...performed the Segmented Memory acquisition based on triggering on any form or flagged error frame condition All Errors our Lister display now shows that every captured frame contains some type of err...

Страница 110: ...l and signaling which is primarily used in automotive applications To complete this lab your scope must be licensed with the CAN LIN trigger and decode option Option AUTO You can verify the installed...

Страница 111: ...signal is too complex to establish a unique trigger point using simple edge triggering This signal is a packet frame of LIN serial bus traffic Let s first set up the scope to intelligently decode this...

Страница 112: ...shed stable triggering The scope is still triggering on any rising edge of channel 1 default trigger condition Let s now set up the scope to trigger on a LIN frame with the ID 21HEX 12 Press the Trigg...

Страница 113: ...layed in red Note that Frame ID 12HEX contains an occasional checksum error If you change to the trigger condition to trigger on ID 0x12 you can observe this particular type of error Let s now capture...

Страница 114: ...hese error conditions 21 Push the horizontal position delay knob to re position the trigger point back to center screen 22 Set the scope s timebase to 200 0 ms div 23 Press the Search front panel key...

Страница 115: ...option 26 Push the horizontal position delay knob to re position the trigger point back to center screen 27 Set the scope s timebase to 1 00 ms div 28 Press the Run Stop front panel to begin repetiti...

Страница 116: ...and timebase setting In this example we have selectively captured approximately 15 seconds of total acquisition time as shown in Figure 77 Note that we can also view the segmented decoded LIN serial d...

Страница 117: ...r condition to trigger on ID 12HEX our Lister display now shows a list of consecutive occurrences of just this particular frame ID as shown in Figure 78 To find out how often the parity bit or checksu...

Страница 118: ...d with the I2 S trigger and decode option Option AUDIO as well as the MSO option You can verify the installed options on your oscilloscope at Help About Oscilloscope 1 Press Default Setup on the scope...

Страница 119: ...e the scope s analog inputs and or logic probe to capture these signals from your system D9 is the audio serially encoded data signal SDATA D8 is the serial clock signal SCLK and D7 is the Word Select...

Страница 120: ...audio data similar to Figure 80 However the scope is not yet triggering on these signals The scope should be randomly auto triggering because the default trigger condition is to trigger on a rising ed...

Страница 121: ...pe s timebase to 10 00 ms div 28 Press Run Stop to stop repetitive acquisitions 29 Tap the Scroll Lister softkey then turn the Entry knob to manually scroll through the lister table As you scroll thro...

Страница 122: ...earch operation as shown in Figure 82 These frames are also marked in orange in the first pointer column of the lister table Your scope should have found and marked approximately 20 occurrences of thi...

Страница 123: ...gger softkey and change to Greater than 42 Tap the Data softkey twice to bring up the keypad then change the value to 10 43 Press the Acquire front panel key 44 Tap the Segmented softkey then tap of S...

Страница 124: ...scilloscope acquisition memory by only capturing important segments of a waveform based on the trigger condition and timebase setting In this example we have selectively captured over 700 ms of total...

Страница 125: ...your scope must be licensed with the FlexRay trigger and analysis option Option FLX You can verify the installed options on your oscilloscope at Help About Oscilloscope 1 Connect the channel 1 probe t...

Страница 126: ...t Baud is defined as 10 Mb s default conditions 11 Press the Back front panel button above power switch to return to the previous menu Your scope should now be decoding FlexRay serial bus traffic as s...

Страница 127: ...rom 00 to 01 in sync with the corresponding data white and FCRC blue To provide more insight on the Rep and Bas settings imagine a more complex FlexRay implementation with 64 static frames and 64 cycl...

Страница 128: ...18 Press Run Stop to stop repetitive acquisitions 19 You can now scroll through available data in the list by using the scroll bar to the right of the list As you scroll through the data tap on a few...

Страница 129: ...ion as shown in Figure 87 These frames are also marked in orange in the first column of the lister table Your scope should have found and marked approximately 20 occurrences of this search operation b...

Страница 130: ...up arrows to the top right of the lister to close the lister menu 31 Press the Acquire front panel key 32 Tap the Segmented softkey double tap on of Segs and set the value to 500 33 Tap the Segmented...

Страница 131: ...Triggering Search Navigation and Segmented Acquisition Labs 4 4000 X Series Oscilloscopes Advanced Training Guide 131 Figure 88 Using the scope s Segmented Memory acquisition to selectively capture m...

Страница 132: ...d options on your oscilloscope at Help About Oscilloscope 1 Connect the channel 1 probe to the Demo 1 terminal and ground 2 Connect the channel 2 probe to the Demo 2 terminal and ground 3 Press Defaul...

Страница 133: ...t D Source is defined as channel 1 and that D Source is defined as channel 2 default conditions Set each Threshold levels to 1 4 V if not set already 16 Press the Back front panel button above power s...

Страница 134: ...ct Serial 1 USB 18 Tap the Trigger on softkey then select Token Packet 19 Tap the PID softkey and select IN as the token we want to trigger on You should now see stable waveform traces on your scope s...

Страница 135: ...trigger is now stable and displaying the entire training signal Tap the double down arrows at the top right of the display to expand the lister to full screen as seen in Figure 92 The eleven decoded m...

Страница 136: ...SB 27 In the Search for field select Handshake Packet 28 Set the PID to find as NAK 29 Press Run Stop to halt acquisitions Above the waveform you will see white arrows that represent the location of N...

Страница 137: ...36 Tap the Current Segment softkey then turn the Entry knob to review all 500 captured segments 37 Set the Current Segment to 500 and note the time tag of the last captured segment Segmented Memory op...

Страница 138: ...Oscilloscopes Advanced Training Guide 4 Serial Bus Decoding Triggering Search Navigation and Segmented Acquisition Labs Figure 93 Using the scope s Segmented Memory acquisition to selectively capture...

Страница 139: ...ll consist of five words using low speed 12 5kbps for simplicity To complete this lab your scope must be licensed with the MIL STD 1553 ARINC 429 serial triggering analysis option Option AER You can v...

Страница 140: ...Set your thresholds on true signals accordingly You should now see ARINC 429 serial information being actively decoded on the bottom of the waveform Keysight s hardware based decoding allows for extr...

Страница 141: ...Start to Label Tap the Label softkey and rotate the Entry knob to select a value of 076 You should now see a stable trigger as a word with label 076 only occurs once in the repetitive training signal...

Страница 142: ...rs 16 Ensure that Search for is set to Label and then tap the Label softkey Use the Entry knob to set a value of 076 White arrows should appear on the top of the waveform below the Lister window These...

Страница 143: ...ister for segmented acquisitions 19 At this point you should still be zoomed into a word with a label of 076 Press the Acquire front panel key and go into the Segmented menu 20 Tap of Segs and when th...

Страница 144: ...nal will consist of five words using low speed 12 5 kbps for simplicity To complete this lab your scope must be licensed with the MIL STD 1553 ARINC 429 serial triggering analysis option Option AER Yo...

Страница 145: ...al the signal voltages are set between 9 V and 14 V but for this example signal they are only 2 5 V MIL STD 1553 protocol suggests a range of 3 6 V Set your thresholds on true signals accordingly You...

Страница 146: ...3 11 There are many different options in the Trigger menu for you to choose from for this example select Sync Error You should now see a stable trigger as a word with a sync error only occurs once in...

Страница 147: ...the top of the waveform below the Lister window These represent the locations of all hits from the search parameters namely all command and segment status word starts There should be 10 11 on the disp...

Страница 148: ...itions 19 At this point you should still be zoomed into a word with a sync error Press the Acquire front panel key and go into the Segmented menu 20 Tap of Segs and when the keypad appears tap Max Thi...

Страница 149: ...Serial Bus Decoding Triggering Search Navigation and Segmented Acquisition Labs 4 4000 X Series Oscilloscopes Advanced Training Guide 149 Figure 102 Zoomed in on a frame with a sync error...

Страница 150: ...150 4000 X Series Oscilloscopes Advanced Training Guide 4 Serial Bus Decoding Triggering Search Navigation and Segmented Acquisition Labs...

Страница 151: ...A Oscilloscope Block Diagram and Theory of Operation DSO Block Diagram 152 ADC Block 152 Attenuator Block 153 DC Offset Block 153 Amplifier Block 153 Trigger Comparator and Trigger Logic Blocks 154 T...

Страница 152: ...ll DSOs The function of this block is to convert the analog input into a series of digital words Most of today s DSOs utilize 8 bit ADCs which will provide 256 unique digital output levels codes These...

Страница 153: ...nuator block also includes switching of the user selectable input impedance 1 M or 50 as well as AC or DC input coupling DC Offset Block When inputting a signal with DC offset such as a digital signal...

Страница 154: ...ing is to be based on just a positive edge crossing of a single channel the trigger logic block would pass the non inverted output of the trigger comparator to the timebase block If you have selected...

Страница 155: ...t operation is turned over to the Display DSP block Although we used an example of triggering at center screen using the horizontal delay position control you can position the trigger point at any poi...

Страница 156: ...156 4000 X Series Oscilloscopes Advanced Training Guide A Oscilloscope Block Diagram and Theory of Operation...

Страница 157: ...k Measurement Comparisons 163 Oscilloscopes have many different specifications that determine the accuracy that signals can be captured and measured But the primary specification of an oscilloscope is...

Страница 158: ...range of approximately 700 mVp p 3 dB 20 Log 0 707 1 0 So you can t expect to make accurate measurements on signals that have significant frequencies near your scope s bandwidth Closely related to an...

Страница 159: ...ng factor comes from let s look at an actual frequency response of a 1 GHz bandwidth scope Figure 105 shows a measured frequency response test 1 MHz to 2 GHz on an Keysight 1 GHz bandwidth oscilloscop...

Страница 160: ...first thing you need to do is determine the rise and fall times of your fastest signals You can usually obtain this information from published specifications for devices used in your designs Step 2 Ca...

Страница 161: ...be approximately 500 MHz If you are able tolerate up to 20 timing errors when making parametric rise time and fall time measurements on your signals then you could use a 500 MHz bandwidth oscilloscope...

Страница 162: ...eries Oscilloscopes Advanced Training Guide B Oscilloscope Bandwidth Tutorial Let s now make some measurements on a digital clock signal with characteristics similar to this example using various band...

Страница 163: ...but 100 MHz bandwidth is clearly insufficient for this 100 MHz digital clock signal Using a 500 MHz bandwidth oscilloscope Figure 107 shows that this scope is able to capture up to the fifth harmonic...

Страница 164: ...0 MHz digital clock the result is that we now have a much more accurate picture of this signal as shown in Figure 108 We can measure faster rise and fall times we observe less overshoot and we can eve...

Страница 165: ...of frequency response which begins to approximate an ideal brick wall filter is sometimes called a maximally flat frequency response The formulas for computing required oscilloscope bandwidth on thes...

Страница 166: ...166 4000 X Series Oscilloscopes Advanced Training Guide B Oscilloscope Bandwidth Tutorial...

Страница 167: ...Oscilloscope Bandwidths for your Application Application note 5989 5733EN Evaluating Oscilloscope Sample Rates vs Sampling Fidelity Application note 5989 5732EN Evaluating Oscilloscopes for Best Wavef...

Страница 168: ...168 4000 X Series Oscilloscopes Advanced Training Guide C Related Keysight Literature...

Страница 169: ...code search 125 frequency measurement 16 28 front panel 7 G Gaussian frequency response 158 165 H help on any topic 8 hold off trigger 44 Horiz key 9 Horizontal Controls 9 I I2C serial bus trigger dec...

Страница 170: ...timebase block 154 Tools Controls 11 tracking cursor mode 16 training signals 6 trigger comparator and trigger logic blocks 154 Trigger Controls 10 trigger hold off 44 Trigger Level knob 10 U USB ser...

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