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Instrument: Agilent Technologies 16533/34A Digitizing Oscilloscope

Agilent Technologies 16533/34A Digitizing Oscilloscope

The Agilent Technologies 16533A and 16534A digitizing oscilloscopes offer basic oscilloscope functionality. The oscilloscope can be easily correlated with other instruments in the Agilent Technologies 16700A/ B-series logic analysis system.
Getting Started
“Calibrating the Oscilloscope” on page 10
“Probing” on page 14
“Acquiring a Waveform” on page 31
“Combining the Oscilloscope with a Logic Analyzer” on page 35
Refining Your Measurement
“Triggering” on page 38
“Vertical and Horizontal Scaling” on page 52
“Changing the Sample Rate” on page 54
“Comparing Channels” on page 56
“Using Markers” on page 75
Tip s
“What Do the Display Symbols Mean?” on page 57
“Changing Waveform Display and Grid” on page 46
“Automatic Measurements and Algorithms” on page 61
“Differences from a Standard Digitizing Oscilloscope” on page 77
“Using Waveform Memories” on page 78
“Loading and Saving Oscilloscope Configurations” on page 79
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Agilent Technologies 16533/34A Digitizing Oscilloscope
•“When Something Goes Wrong” on page 80
Specifications and Characteristics” on page 85
Main System Help (see the Agilent Technologies 16700A/B-Series Logic Analysis System help volume)
Glossary of Terms (see page 93)
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Agilent Technologies 16533/34A Digitizing Oscilloscope
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Contents

Agilent Technologies 16533/34A Digitizing Oscilloscope
1 Agilent Technologies 16533/34A Digitizing Oscilloscope
Calibrating the Oscilloscope 10
Calibration Reference 12
Probing 14
Table of Compatible Probes 14 Selecting the Proper Probe 15 Compensating the Compensated Passive Divider Probe 17 Probe Loading 18 Descriptions of Probe Types 22 Surface Mount Probing 29
Acquiring a Waveform 31
Autoscale 32 Specifying a Measurement 33
Combining the Oscilloscope with a Logic Analyzer 35
Oscilloscope Triggers Logic Analyzer 35 Logic Analyzer Triggers Oscilloscope 36 Logic Analyzer and Oscilloscope Correlate Data 36
Triggering 38
Trigger Concepts 38 Edge Triggering 40 Pattern Triggering 41 Delayed Triggering 42 Getting a Stable Trigger 43 The Trigger Setup Window 44
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Contents
Changing Waveform Display and Grid 46
Zooming In 46 Changing the Persistence of the Waveform 46 Viewing Noisy Waveforms with Averaging 48 Changing Display Colors 50 Changing the Grid 50
Vertical and Horizontal Scaling 52
Changing the Sample Rate 54
Comparing Channels 56
What Do the Display Symbols Mean? 57
Display Setup Window 59
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Contents
Automatic Measurements and Algorithms 61
How the Scope Makes Measurements 62 Average Voltage (Vavg) 63 Period 63 Rise Time 63 Fall Time 64 Negative and Positive Pulse Width ( Frequency 65 Base Voltage (Vbase) 66 Top Voltage (Vtop) 66 Preshoot 67 Overshoot 68 Peak-to-Peak Voltage (Vpp) 68 Minimum Voltage (Vmin) 69 Maximum Voltage (Vmax) 69 Time of Minimum Voltage (Tmin) 70 Time of Maximum Voltage (Tmax) 70 Voltage Amplitude (Vamp) 70 Vdcrms (Root Mean Square Voltage, DC) 71 About the Measurements 71 Increasing the Accuracy of Your Measurements 73
±Width) 64
Using Markers 75
About Automatic Time Markers 76
Differences from a Standard Digitizing Oscilloscope 77
Using Waveform Memories 78
Loading and Saving Oscilloscope Configurations 79
When Something Goes Wrong 80
Error Messages 80 Calibration Problems 80 Triggering Problems 80 Other Problems 81
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Contents
Specifications and Characteristics 85
What is a Specification 88 What is a Characteristic 88 What is a Calibration Procedure 88 What is a Function Test 89
Run/Group Run Function 90
Checking Run Status 91 Demand Driven Data 92
Glossary
Index
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Agilent Technologies 16533/34A Digitizing Oscilloscope

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Chapter 1: Agilent Technologies 16533/34A Digitizing Oscilloscope

Calibrating the Oscilloscope

Calibrating the Oscilloscope
The oscilloscope requires a full operational accuracy calibration by you or a service department whenever
it has been 6 months or 1,000 hours of use since last full calibration.
the ambient temperature changes more than 10 degrees C from the
temperature at the time of the last full calibration.
the frame configuration changes.
you need to optimize measurement accuracy.
You will get more accurate measurements from the oscilloscope if you perform the operational accuracy calibration at least once a year.
NOTE: Channel skew calibration requires a multi-board oscilloscope. The procedure
cannot be performed on single-board (2-channel) oscilloscopes.
To calibrate the oscilloscope
This is also covered in the Logic Analysis System Installation Guide. Since this procedure requires you to turn off the system, print this information if you do not have access to the Installation Guide.
1. If your oscilloscope has more than two channels, disconnect the short cables on the back of the module that connect the boards.
2. Unprotect the memory.
a. Turn off the Agilent Technologies 16700A/B-series frame.
b. Take the oscilloscope module out of the frame. See the Logic Analysis
System Installation Guide.
c. Set the PROTECT/UNPROTECT switch to UNPROTECT.
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Chapter 1: Agilent Technologies 16533/34A Digitizing Oscilloscope
Calibrating the Oscilloscope
d. Put the oscilloscope back in the frame.
3. Turn on the 16700A/B-series frame and wait for it to finish booting. You will get a more accurate calibration if you warm up the system for 30 minutes before calibrating the oscilloscope.
4. Select the oscilloscope icon, and choose Calibration...
5. Select the procedure ADC through Logic Trigger. The calibration software will tell you what cables need to be attached.
6. Select the Run button.
7. Select the procedure Ext Trig Skew and connect the cables as directed.
8. Select the Run button.
9. Optional - Calibrate the oscilloscope as a multi-board module.
a. Perform the ADC through Logic Trigger and Ext Trig Skew calibrations
on each oscilloscope board first.
b. In the system window, choose Exit from the File menu.
c. Connect the oscilloscopes together with the short board interconnect
cables. Connect the first boards TRIG OUT to the next boards TRIG IN until all boards are connected.
d. Start a session.
e. Select the oscilloscope icon and choose Calibration.
f. Select the procedure Channel Skew and connect the cables as
directed.
10. After you have finished calibrating, protect the memory. Follow the steps given above for unprotecting, setting the switch to PROTECT instead.
See Also Logic Analysis System Installation Guide
Calibration Reference on page 12
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Chapter 1: Agilent Technologies 16533/34A Digitizing Oscilloscope
Calibrating the Oscilloscope
Calibration Reference
ADC
The ADC calibration procedure produces a linearization table which is applied to the data out of the analog-to-digital converters (ADC) to undo the effects of a non-linear, analog-to-digital conversion.
Gain
The Gain calibration procedure measures the actual attenuation of the attenuators and measures the actual gain of the preamps.
Offset
The Offset calibration procedure determines the actual offset value that places a null signal in center screen.
Hysteresis
The Hysteresis calibration procedure determines the hardware setting which is closest to achieving a hysteresis of 0.28 screen divisions.
Trigger Level
The Trigger Level calibration procedure determines the actual trigger level values for all possible voltage levels across the screen.
Trigger Delay
The Trigger Delay calibration procedure determines a time delay which correctly lines up the point at which a trace crosses the trigger level with the trigger time.
Logic Trigger
The Logic Trigger calibration procedure determines settings which affect the accuracy of duration trigger measurements.
Ext Trig Skew
The Ext Trig Skew calibration procedure lines up the external trigger edge with the trigger time when triggering on the external channel.
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Chapter 1: Agilent Technologies 16533/34A Digitizing Oscilloscope
Calibrating the Oscilloscope
Channel Skew
The Channel Skew calibration procedure is only available for multi­board oscilloscope modules. It deskews the trigger channel and data channels which are on different boards.
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Chapter 1: Agilent Technologies 16533/34A Digitizing Oscilloscope

Probing

Probing
The probes covered in the topics below are 1:1 Passive Probes, Active Probes, Current Probes, Compensated Passive Divider Probes, Differential Probes, and Resistive Divider Probes.
•“Table of Compatible Probes” on page 14
•“Selecting the Proper Probe” on page 15
•“Compensating the Compensated Passive Divider Probe” on page 17
•“Probe Loading” on page 18
•“Descriptions of Probe Types” on page 22
•“Surface Mount Probing” on page 29
Table of Compatible Probes
* Most frequently used
Agilent Model Probe Type Band- Input Div Input R Input C Numbers width Z ratio
COMPENSATED DIVIDER
10441A Compensated 500 1 Mohm 10:1 1 Mohm 9 pF
*1160A Compensated 500 1 Mohm 10:1 10 Mohm 9 pF Passive Divider MHz
1161A Compensated 500 1 Mohm 10:1 10 Mohm 10 pF Passive Divider MHz
1162A High Impedance 25 1 Mohm 1:1 1 Mohm 50 pF + Passive MHz scope C
RESISTIVE DIVIDER
1163A Resistive 1.5 50 ohm 10:1 500 ohm 1.5 pF Divider GHz
54006A Resistive 6 50 ohm 10:1 500 ohm 0.25 pF Divider GHz 20:1 or 1Kohm
ACTIVE
*1144A Active 800 50 ohm 10:1 1 Mohm 2 pF MHz
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Chapter 1: Agilent Technologies 16533/34A Digitizing Oscilloscope
*1145A Dual Channel 750 50 ohm 10:1 1 Mohm 2 pF Small Geometry MHz Active
1141A Differential 200 50 ohm 1:1 1 Mohm 7 pF MHz 10:1 9 Mohm 3.5 pF 100:1 10 Mohm 2.0 pF
54701A Active 2.5 50 ohm 10:1 100 Kohm 0.6 pF GHz
CURRENT
1146A Current 100 1 Mohm n/a n/a n/a kHz
See Also Descriptions of Probe Types on page 22
Channel Setup Window on page 33 for setting input impedance and
coupling
Selecting the Proper Probe
Use the flowchart below for selecting the proper type of probe. A comparison of features, tradeoffs, and applications of the probes are available after the flowchart.
Probing
1:1 Passive Probe
Features
No attenuation of waveform.
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Chapter 1: Agilent Technologies 16533/34A Digitizing Oscilloscope
Probing
Tradeoffs High capacitive loading and low bandwidth.
Applications Measuring small, low-bandwidth waveforms when no
attenuation can be tolerated such as power supply ripple.
Active Probe
Features
Best overall combination of low resistive and capacitive
loading. High bandwidth.
Tradeoffs Higher cost, limited dynamic range, requires power.
Applications ECL, CMOS, GaAs probing, analog circuit probing,
transmission line probing, source resistance
10 kohm, op amp
probing, most accurate for general measurements of circuits of unknown impedance.
Compensated Passive Divider Probe
Features
Very low resistive loading, accurate amplitude measurements,
large dynamic range, and low cost.
Tradeoffs Capacitive loading <10 pF, lower bandwidth than active or
50-ohm resistive divider probes.
Applications General purpose probing, probing high-impedance nodes
10 Kohm), op amp probing, CMOS probing (if bandwidth is
( adequate), TTL probing (if bandwidth is adequate)
Current Probe
Features
Measures both ac and dc currents on a scope, with minimal
circuit loading.
Tradeoffs Large size.
Applications Power measurements, automotive measurements,
industrial measurements, motors, dynamoes, and alternators.
Differential Probe
Features
High common mode rejection ratio, easy viewing of small waveforms with large dc offsets, more accurate than subtracting one channel from another.
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Chapter 1: Agilent Technologies 16533/34A Digitizing Oscilloscope
Probing
Tradeoffs Bigger than a passive probe, high cost, requires power, and
lower bandwidth than other probes.
Applications Measuring waveforms not referenced to the scope ground,
troubleshooting power supplies, and differential amplifier probing.
Resistive Divider Probe
Features
Highest bandwidth, lowest capacitive load, lower cost than
active probes, flat pulse response, good timing measurement accuracy.
Tradeoffs Relatively heavy resistive loading.
Applications ECL probing, GaAs probing, and transmission line probing.
See Also Descriptions of Probe Types on page 22
Table of Compatible Probes” on page 14
Compensating the Compensated Passive Divider Probe
Before you can have a flat frequency response when using a Compensated Passive Divider Probe, the probes cable capacitance and scope input capacitance must be compensated. One of the compensating capacitors in the probe is adjustable so you can optimize the step response for flatness.
1. Connect the probe to the BNC Output, labeled AC/DC CAL, on the back of the oscilloscope.
2. Connect the probe ground lead to ground.
3. Select the oscilloscope icon and choose Calibration...
4. At the bottom of the calibration window, set BNC Output to Probe Comp and close the window.
5. Select the oscilloscope icon and choose Setup/Display...
6. Select the Autoscale menu and choose Continue.
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Chapter 1: Agilent Technologies 16533/34A Digitizing Oscilloscope
Probing
7. You should see a waveform similar to one of the following.
8. If necessary, adjust the probes compensating capacitor. Set the scope to keep running by selecting the Run Repetitive button.
Probe Loading
Probe Resistance and Capacitance Characteristics
There are two major factors influencing probe selection: the load the probe imposes on your circuit and the required bandwidth of your circuit with the probe. This is discussed in three sections, below.
Probe Resistance and Capacitance Characteristics (see page 18)
Probe Ground Lead Characteristics (see page 20)
Understanding System Bandwidth at the Probe Tip (see page 20)
The probe load has both resistive and capacitive components. In addition, the inductance in the probe ground lead causes ringing.
The probe resistance to ground forms a voltage divider network with the source resistance of your circuit. This reduces the waveform amplitude and the dc offset. For example, if the probes resistance is 9 times the Thevenin equivalent resistance of your circuit, the waveform amplitude is reduced by about 10 percent. Therefore, if your waveform has a +5 V to 0.8 V range, the scope probe system shows a 4.5 V to 0.72 V range.
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Chapter 1: Agilent Technologies 16533/34A Digitizing Oscilloscope
NOTE: At high frequencies, the probe reactance dominates the resistance.
The probe capacitive loading (Cin) to ground forms an RC circuit with the resistance of your circuit (R the probe and scope (R
). The time constant of this RC circuit slows
in
) and the resistance looking into
source
the rise time of any transitions, increases the slew rate, and introduces delay in the actual transition time. The approximate rise time of a simple RC circuit is: t
R
RC
Tot al
= 2.2R
= [RinR
Tot alCin
source
where
]/[Rin + R
source
]
Thus, for circuit resistance of 100 ohm, a scope probe system resistance of 1 Mohm, and a probe capacitance of 8 pF, the real rise time due to probe loading is:
= [1 Mohm (100 ohm)]/[1 Mohm + 100 ohm], approximately 100
R
Tot al
ohm.
= 2.2(100 ohm)(8 pF), approximately 1.8 ns.
t
RC
Probing
Therefore, the rise time of your circuit cannot be faster than approximately 1.8 ns, even though it might be faster without the probe.
If the output of the circuit under test is current-limited (as is often the case for CMOS), the slew rate is limited by the relationship dV/dT = I/C.
Perhaps you have connected a scope to a circuit for troubleshooting only to have the circuit operate correctly after connecting the probe. The capacitive loading of the probe can attenuate a glitch, reduce ringing or overshoot of your waveform, or slow an edge just enough that a setup or hold time violation no longer occurs.
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Chapter 1: Agilent Technologies 16533/34A Digitizing Oscilloscope
Probing
Probe Ground Lead Characteristics
NOTE: If you print this page, subscripts and superscripts appear on the main line of
text. If a number seems to be in an odd place in the printed copy, it is probably a superscript.
The inductance of the probes ground lead forms an LC circuit with the probes capacitance and the output capacitance of the circuit under test, including any parasitic capacitance of PC board traces, and so on. The ringing frequency (F) of this circuit is:
F = (2 (3.14) (LC)
1/2)-1
If the rise time of the waveform is sufficient to stimulate this ringing, the ringing can appear as part of your captured waveform. To calculate the ringing frequency, you can assume that the probes ground lead has an inductance of approximately 25 nH per inch. So, a probe with a capacitance of 8 pF and a 4-inch ground lead has a ringing frequency of approximately:
1/2)-1
F = (2 (3.14) [(25 nH) (4 inches) (8 pF)]
= 178 MHz
Understanding System Bandwidth at the Probe Tip
The 178 MHz does not include your circuit capacitance. Therefore, a waveform with a rise time of less than 1.9 ns can stimulate ringing.
= 0.35/178 MHz = 1.9 ns
t
rise
To minimize the ringing effect, you should use a probe ground lead that is as short as possible. Some probes add a ferrite bead to the ground lead to reduce ringing. However, adding the ferrite bead also increases the ground impedance which reduces the common mode rejection of the probe.
System bandwidth is the bandwidth of the scope probe system. System bandwidth affects measurements because the probe becomes part of the circuit being measured. The rise time that is measured depends on the actual rise time, the rise time of the scope probe system, and the
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Chapter 1: Agilent Technologies 16533/34A Digitizing Oscilloscope
Probing
rise time of the RC circuit formed by the source resistance and the scope probe system resistance and capacitance.
t
meas
= [t
act
2
+ t
RC
2
+ t
sys
2
1/2
]
where
= the measured rise time.
t
meas
= the actual rise time of the waveform being measured.
t
act
= the rise time of the RC circuit formed by the source resistance
t
RC
and the scope probe system resistance and capacitance.
= the rise time of the scope probe system.
t
sys
NOTE: Often the bandwidth of the scope probe system is specified. The rise time is
calculated using the following equation.
= 0.35/SystemBW
t
sys
If the rise time of the scope probe system is not specified, it can be calculated using the following formula.
probe
2
+ t
= [t
t
sys
scope
1/2
2
]
For example, if the scope probe system rise time is 600 ps, the probe loading rise time (t
) is 600 ps, and the waveform has a 1-ns rise time,
RC
then the measured rise time is:
t
= [(1 ns)2 + (600 ps)2 + (600 ps)2]
meas
1/2
= 1.3 ns
The answer is in error by 30%.
However, if the scope probe system rise time is 190 ps, the probe loading rise time is 190 ps, and the waveform has a 1-ns rise time, then the measured rise time is:
= [(1 ns)2 + (190 ps)2 + (190 ps)2]
t
meas
1/2
= 1.03 ns
Now the error is only 3%.
You may find it useful to memorize three system bandwidth rules:
1. The combined rise time of the scope probe system and the probe loading should be less than 1/3 of the rise time of the waveform you are measuring to keep errors below 5%, and less than 1/7 of the rise time of the waveform you are measuring to keep errors below 1%.
2. Rise time and bandwidth are related by the following approximations: rise time = 0.35/bandwidth and bandwidth = 0.35/rise time.
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Chapter 1: Agilent Technologies 16533/34A Digitizing Oscilloscope
Probing
3. Rise times add approximately as the square root of the sum of the squares (for systems with minimal peaking).
NOTE: Because every scope probe has a different loading effect on your circuit, you
should use the equation given for the type of scope probe you are using.
See Also “Descriptions of Probe Types on page 22
Descriptions of Probe Types
For each of the probe types listed below, the description gives a summary of features and tradeoffs and a short text description. Most of the probe types also give a sample rise time calculation.
•“1:1 Passive Probes” on page 22
•“Active Probes” on page 24
•“Compensated Passive Divider Probes” on page 25
•“Current Probes” on page 27
•“Differential Probes” on page 27
•“Resistive Divider Probes” on page 28
1:1 Passive Probes
Features No attenuation of waveform.
Tradeoffs High capacitive loading and low bandwidth.
Applications Measuring small, low-bandwidth waveforms when no
attenuation can be tolerated such as power supply ripple.
The 1:1 passive probes provide a way to connect the input impedance of the scope directly to your circuit with minimum attenuation due to the resistive loading of the probe. However, 1:1 probes do have very high capacitive loading which is much larger than that of the scope.
There are two types of 1:1 passive probes. One type is designed to work
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Chapter 1: Agilent Technologies 16533/34A Digitizing Oscilloscope
Probing
with the scopes input set to high impedance (1 Mohm) and uses a lossy cable to keep the probe from ringing. The other type is designed to work with the scopes input set to low impedance (50 ohm) and uses a 50-ohm coaxial cable.
Example Rise Time Calculation
Given the following circuit using the Agilent Technologies 1162A probe,
the input resistance is:
= R
R
in
= 1 Mohm
scope
The total resisitance is:
= (RinR
R
Tot al
= 1 Mohm(50 ohm)/(1 Mohm + 50 ohm) = 50 ohm
R
Tot al
source
)/(Rin + R
source
)
From the Table of Compatible Probes, the probe capacitance is 50 pF. Therefore, the capacitive load is:
= C
C
in
probe
+ C
= 50 pF + 7 pF = 57 pF
scope
The rise time due to circuit loading is:
= 2.2R
t
RC
Tot alCin
tRC = 2.2(50 ohm)(57 pF) = 6.2 ns
From the Table of Compatible Probes, the scope probe system has a bandwidth of 25 MHz. Therefore, the rise time of the scope probe system is: t
= 0.35/25 MHz = 14 ns
t
Sys
The measured rise time is: t
2
ns)
+ (6.2 ns)2 + (14 ns)2]
= 0.35/SystemBW
Sys
= [t
meas
1/2
= 140.8 ns
act
2
+ t
RC
2
+ t
sys
2
1/2
]
t
= [(140
meas
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Chapter 1: Agilent Technologies 16533/34A Digitizing Oscilloscope
Probing
Active Probes
Features Best overall combination of low resistive and capacitive
loading. High bandwidth.
Tradeoffs Higher cost, limited dynamic range, requires power.
Applications ECL, CMOS, GaAs probing, analog circuit probing,
transmission line probing, source resistance probing, most accurate for general measurements of circuits of unknown impedance.
An active probe has a buffer amplifier at the probe tip. This buffer amplifier drives a 50-ohm cable terminated in 50 ohms at the scope input. Active probes offer the best overall combination of resistive loading, capacitive loading, and bandwidth.
10 kohm, op amp
Example Rise Time Calculation
Given the following circuit using the Agilent Technologies 1152A probe,
the input resistance is:
= 100 kohm. The total input resistance is:
R
in
= (RinR
R
Tot al
= 100 ohm(50 ohm)/(100 ohm + 50 ohm) = 50 ohm
R
Tot al
source
)/(Rin + R
source
)
The rise time due to circuit loading is:
= 2.2R
t
RC
Tot alCtip
tRC = 2.2(50 ohm)(0.6 pF) = 66 ps
Because the rise time of the scope probe system is not given in the Table of Compatible Probes, we will have to calculate it using the
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Chapter 1: Agilent Technologies 16533/34A Digitizing Oscilloscope
Probing
bandwidth of the probe (2.5 GHz) and the bandwidth of the scope (500 MHz). Therefore, the rise time of the scope probe system is:
= 0.35/ProbeBW = 0.35/2.5 GHz = 140 ps
t
probe
= 0.35/ScopeBW = 0.35/500 MHz = 700 ps
t
scope
t
= [t
sys
t
= [(140 ps)2 + (700 ps)2]
sys
probe
2
+ t
scope
2
1/2
]
1/2
= 714 ps
The measured rise time is:
t
meas
= [t
act
2
+ t
RC
2
+ t
sys
2
1/2
]
t
= [(2 ns)2 + (66 ps)2 + (714 ps)2]
meas
1/2
= 2.12 ns
Compensated Passive Divider Probes
Features Very low resistive loading, accurate amplitude measurements,
large dynamic range, and low cost.
Tradeoffs Capacitive loading <10 pF, lower bandwidth than active or
50-ohm resistive divider probes.
Applications General purpose probing, probing high-impedance nodes
10 Kohm), op amp probing, CMOS probing (if bandwidth is
( adequate), TTL probing (if bandwidth is adequate).
The compensated passive divider probe is the most common type of scope probe. The 9-Mohm resistor in the tip forms a 10:1 voltage divider with the 1-Mohm input resistance of the scope.
To have a flat frequency response, the probe tip capacitance is compensated by the probes cable capacitance, a compensating capacitor, and the scope input capacitance. The compensating capacitor is adjustable so you can optimize the step response for flatness.
Not all 9-Mohm divider probes work with all 1-Mohm scope inputs. The probe data sheet shows the range of scope input capacitance it can accommodate. You must make sure that the input capacitance of the scope is within that range.
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Chapter 1: Agilent Technologies 16533/34A Digitizing Oscilloscope
Probing
Example Rise Time Calculation
Given the following circuit using an Agilent Technologies 1160A probe,
the input resistance is:
= R
R
in
= 9 Mohm + 1 Mohm = 10 Mohm
R
in
probe
+ R
scope
The capacitive load is:
= C
C
in
[C
probe+Ccable+Ccomp+Cscope
tip
+ {[C
probe(Ccable+Ccomp+Cscope
]}
)]/
This number is calculated for the scope and scope probe combination, and is shown in the Table of Compatible Probes.
The total resistance is: R
= 10 Mohm(50ohm)/(10 Mohm + 50ohm) = 50 ohm
R
Tot al
Total
= (RinR
source
)/(Rin + R
source
)
The rise time due to circuit loading is: t
= 2.2R
RC
Tot alCin
tRC = 2.2(50 ohm)(7.5 pF) = 825 ps
From the Table of Compatible Probes, the bandwidth of the scope probe system is 500 MHz. Therefore, the rise time of the scope probe system is:
= 0.35/SystemBW
t
sys
= 0.35/500 MHz = 700 ps
t
sys
The measured rise time is:
= [(t
t
meas
t
= [(2 ns)2 + (825 ps)2 + (700 ps)2]
meas
)2 + (tRC)2 + (t
act
sys
)2]
1/2
1/2
= 2.27 ns
Remember that probe input impedance for compensated passive divider probes is complex. A simple RC network serves only as a first­order approximation.
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Chapter 1: Agilent Technologies 16533/34A Digitizing Oscilloscope
Probing
Current Probes
Features Measures both ac and dc currents on a scope, with minimal
circuit loading.
Tradeoffs Large size.
Applications Power measurements, automotive measurements,
industrial measurements, motors, dynamoes, and alternators.
Scopes are designed to measure voltage, but by using a current probe you can measure current. A current probe measures current in a wire by enclosing the wire. Therefore, no electrical connection is needed.
Current probes generally use one of two technologies. The simplest uses the principle of a transformer, with one winding of the transformer being the measured wire. Because transformers only work with alternating voltages and currents, current probes of this type cannot measure direct current.
The other type of current probe uses the Hall effect principle. The Hall effect produces an electric field in response to an applied magnetic field. While this technique requires a power supply, it measures both alternating and direct current.
Differential Probes
Features High common mode rejection ratio, easy viewing of small
waveforms with large dc offsets, more accurate than subtracting one channel from another.
Tradeoffs Bigger than a passive probe, high cost, requires power, and
lower bandwidth than other probes.
Applications Measuring waveforms not referenced to the scope ground,
troubleshooting power supplies, and differential amplifier probing.
A differential probe is a high-impedance differential amplifier with two probe tips; a non-inverting input and an inverting input. These two inputs feed a differential amplifier which in turn drives the 50-ohm input of the scope. The main advantage of differential probes is their ability to reject waveforms that are common to both inputs. This type of probe is often used in floating ground applications.
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Chapter 1: Agilent Technologies 16533/34A Digitizing Oscilloscope
Probing
You could duplicate a differential probe by using two passive probes and subtracting the two scope channels. However, the electrical paths of the differential probe are carefully matched to give a high common mode rejection ratio (CMRR). The higher the CMRR, the smaller the waveforms you can view in the presence of unwanted noise.
Resistive Divider Probes
Features Highest bandwidth, lowest capacitive load, lower cost than
active probes, flat pulse response, good timing measurement accuracy.
Tradeoffs Relatively heavy resistive loading.
Applications ECL probing, GaAs probing, and transmission line
probing.
Resistive divider probes are designed for scopes with a 50-ohm input impedance. The probe tips of the Agilent Technologies 1163A or 54006A have either a 450-ohm or 950-ohm series resistor. The probe cable is a 50-ohm transmission line. Because the cable is terminated in 50 ohms at the scope input, it looks like a purely resistive 50-ohm load when viewed from the probe tip. Therefore, the resistive divider probe is flat over a wide range of frequencies, limited primarily by the parasitic capacitance and inductance of the 450-ohm or 950-ohm resistor and the fixture that holds it. The resistive load of the probe to your circuit is either 500 ohm or 1 kohm, depending on the probe.
Example Rise Time Calculation
This type of probe has the smallest capacitive load of any probe. The small capacitance and wide bandwidth make this probe type a good choice for wide bandwidth measurements or time-critical measurements.
Given the following circuit using the Agilent Technologies 1163A probe,
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Chapter 1: Agilent Technologies 16533/34A Digitizing Oscilloscope
the input resistance is:
= R
R
in
R
in
+ R
tip
= 450 ohm + 50 ohm = 500 ohm
scope
The total resistance is:
= (RinR
R
Tot al
= 500 ohm(50ohm)/(500 ohm + 50ohm) = 45 ohm
R
Tot al
source
)/(Rin + R
source
)
Probing
The rise time due to circuit loading is:
= 2.2R
t
RC
Tot alCtip
tRC = 2.2(45 ohm)(1.5 pF) = 165 ps
From the Table of Compatible Probes, the bandwidth of the scope probe system is 1.5 GHz. Therefore, the rise time of the scope probe system is:
= 0.35/SystemBW
t
sys
= 0.35/1.5 GHz = 230 ps
t
sys
The measured rise time is:
= [(t
t
meas
t
= [(2 ns)2 + (165 ps)2 + (230 ps)2]
meas
)2 + (tRC)2 + (t
act
sys
)2]
1/2
1/2
= 2.02 ns
Surface Mount Probing
The Agilent Technologies 10467A 0.5 mm MicroGrabber Accessory Kit is designed for using the Agilent Technologies 116x family of probes when you are probing fine-pitch (0.5 mm to 0.8 mm) SMT (Surface
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Chapter 1: Agilent Technologies 16533/34A Digitizing Oscilloscope
Probing
Mount Technology) devices. The kit contains enough parts for two probes.
The Agilent Technologies 116x probe tip plugs into the single-lead end of the dual-lead adapter. The MicroGrabber connects to the red lead. You can also use a MicroGrabber on the black lead, which you should connect to your circuits ground. You can also connect the dual-lead end to circuit pins that are 0.635 mm (0.025 inch) in diameter.
The kit is intended for use with voltages no greater than ac peak).
±40 V (dc and
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Chapter 1: Agilent Technologies 16533/34A Digitizing Oscilloscope

Acquiring a Waveform

Acquiring a Waveform
The two ways to acquire a waveform with the oscilloscope are Autoscale and Run. When you use Run, you can modify settings to fine-tune your measurement.
You can also save acquired waveforms using waveform memories. (see page 78)
Autoscale
Autoscale automatically adjusts volts per division and offset so that the waveform fits into the display. It also attempts to set the seconds per division so that three periods of the waveform are displayed.
Specifying a Measurement
To set up a measurement, first specify the channel setup then the trigger. Based on your waveform you may need to change the offset and scale to get accurate measurements.
A faster way to set up your measurement is to first autoscale, then adjust only the settings you are interested in.
Running
The default acquisition mode is single-shot. To take another acquisition immediately after the first one, select the Run Repetitive button.
The scope does not support any modes other than real-time mode. You can turn on averaging or accumulate under the Display tab. However, because of the way the oscilloscope samples, this is not the same as the equivalent time mode of a stand-alone oscilloscope.
NOTE: Selecting the Run button in an instrument window only runs that instrument.
To run all active instruments, select Run All in the System or Workspace window, or Group Run in the window of any instrument included in a group run. If the scope is triggered by another instrument, do not change settings while the scope is waiting for its trigger or it may not trigger.
See Also Run/Group Run Function on page 90
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Acquiring a Waveform
Autoscale on page 32
Specifying a Measurement” on page 33
Using Waveform Memories on page 78
Differences from a Standard Digitizing Oscilloscope” on page 77
Combining the Oscilloscope with a Logic Analyzer on page 35
Autoscale
Autoscale automatically optimizes the waveform display for each channel that is turned on. It sets volts per division and offset so that the waveform fits into the middle of the display, and adjusts the timebase (horizontal axis) to show three periods. When signals have different periods, the signal on the lowest-numbered channel is used to set the horizontal scale. If none of the signals show activity, the timebase is set to 200 ns per division.
Autoscale also changes the trigger settings. The trigger channel is channel 1 unless the signal on channel 1 has no detectable voltage change. Triggering is limited to channels 1 and 2; no higher-numbered channels can be set, but they will be autoscaled. The trigger mode is set to the first rising edge and autotriggered. The trigger level is set to the 60% threshold of the signal. If both channel 1 and channel 2 have flat signals, the trigger source is set to channel 2 and the trigger level is set to channel 2s offset.
The settings changed by autoscale are:
Setting Default Algorithm
V/div 200 mV/div Waveform fits within the middle (Scale) 6 divisions of the display
Channel Offset 0 Waveform is centered vertically
Sec/div 200 ns/div Fit three periods on screen (Scale)
Time offset 0 Always centers waveform around trigger (Delay)
Trigger mode rising edge Always sets trigger to rising edge
Trigger sweep autotrigger Always sets trigger to autotrigger
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Acquiring a Waveform
Trigger level not applicable Always sets level to near 60% threshold if a non-constant signal is detected
Trigger occurrence 1 Always sets occurrence to 1
Trigger source channel 1 Checks channel 1 for an active signal; if signal is flat, sets to channel 2
Specifying a Measurement
1. Connect probes. (see page 14)
2. Set up the channel. (see page 33)
3. Set the display mode. (see page 59)
4. Specify trigger. (see page 38)
5. Select the Run Repetitive button to start the acquisition.
6. Save particular waveforms to waveform memory. (see page 78)
The data is automatically displayed in the oscilloscope window. You can also connect it to a display tool in order to correlate the oscilloscope with a logic analyzer.
See Also Combining the Oscilloscope with a Logic Analyzer on page 35
Probing on page 14
Channel Setup Window on page 33
Display Setup Window on page 59
Triggering on page 38
Using Waveform Memories on page 78
Channel Setup Window
To access the Channel Setup window, select the Setup... button under the Channels tab. Use this window to specify your probe type and probe impedance. After the initial setup, you may want to use this window to adjust channel skew.
On/Off Use this button to turn the channel on or off. You can also do
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Acquiring a Waveform
this from the main oscilloscope window.
Name Channel names can be a maximum of 10 characters long.
Customized names appear anywhere the channel is labeled.
Probe The probe attenuation factor. The arrow keys scroll through the
standard probe attenuation values, or you can enter non-standard values by typing in the field. Probe attenuation affects the display and marker measurements.
Input Z / Coupling Probe input impedance. Incorrect impedance will
cause bad measurements. See the “Table of Compatible Probes on page 14 for suggested values.
Skew Adjust for channel-to-channel skew caused by differing
electrical path lengths of the probes. To deskew the channels for multi­board oscilloscopes, run Channel Skew in the calibration utility.
Preset Select from TTL, ECL, and User. TTL sets the scale to 1 V/div
and the offset to 2.50 V. ECL sets the scale to 250 mV/div and the offset to -1.3 V. User defaults to TTL values, but if you change the Scale or Offset settings, the Preset field changes to User.
Scale Scale affects the vertical axis of the waveform display. You can
change it through either the arrow buttons or by typing in the field. It is the same scale field as in the main oscilloscope window.
Offset Offset moves the waveform vertically in the display window.
Parts of the waveform that go offscreen are clipped, which may affect any automatic measurements you run. The offset field also appears in the main oscilloscope window.
You can also display the Channel Setup window by selecting a channel in the grid and choosing Channels... from the menu.
See Also Calibrating the Oscilloscope on page 10
Probing on page 14
Vertical and Horizontal Scaling on page 52
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Combining the Oscilloscope with a Logic Analyzer

Combining the Oscilloscope with a Logic Analyzer
If you want to make a measurement with a logic analyzer and an oscilloscope, there are three cases:
•“Oscilloscope Triggers Logic Analyzer” on page 35
•“Logic Analyzer Triggers Oscilloscope” on page 36
•“Logic Analyzer and Oscilloscope Correlate Data” on page 36
See Also The Intermodule Window (see the Agilent Technologies 16700A/B-Series
Logic Analysis System help volume) for a generic approach.
Oscilloscope Triggers Logic Analyzer
1. Select the toolbar's Workspace button.
2. In the Workspace window, drag both instruments on to the workspace.
3. Connect both to the same display tool.
4. In the Correlation Error dialog that appears, select Group Run for the scope and Oscilloscope for the logic analyzer.
5. Select the Group Run or Run All button to start the acquisition.
6. To view the waveforms together, open the display tool.
For a Waveform display, select one of the labels and choose Insert
before... or Insert after.... In the Label Dialog, select the label you want
to insert, then select the Apply button.
For the other tools, the oscilloscope labels are already available.
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Combining the Oscilloscope with a Logic Analyzer
Logic Analyzer Triggers Oscilloscope
NOTE: When the logic analyzer triggers the oscilloscope, if you are changing
oscilloscope settings when the trigger occurs it may be missed. The message bar and Run Status window show "Waiting for IMB Arm" when this occurs. When this happens, select the Stop button and restart the acquisition.
1. Select the toolbars Workspace button.
2. In the Workspace window, drag both instruments on to the workspace.
3. Connect both to the same display tool.
4. In the Correlation Error dialog that appears, select Group Run for the logic analyzer and the logic analyzer description for the oscilloscope.
5. A Trigger Advisory dialog box may appear. Select Trigger Immediate.
6. Select the Group Run or Run All button to start the acquisition.
7. To view the waveforms together, open the display tool.
For a Waveform display, select one of the labels and choose Insert
before... or Insert after.... In the Label Dialog, select the label you want
to insert, then select the Apply button.
For the other tools, the oscilloscope labels are already available.
Logic Analyzer and Oscilloscope Correlate Data
1. Select the toolbar's Workspace button.
2. In the Workspace window, drag both instruments on to the workspace.
3. Connect both into same display tool.
4. In the Correlation Error dialog that appears, select Group Run for both instruments.
5. Select the Group Run or Run All button to start the acquisition.
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Combining the Oscilloscope with a Logic Analyzer
6. To view the waveforms together, open the display tool.
For a Waveform display, select one of the labels and choose Insert
before... or Insert after.... In the Label Dialog, select the label you want
to insert, then select the Apply button.
For the other tools, the oscilloscope labels are already available.
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Chapter 1: Agilent Technologies 16533/34A Digitizing Oscilloscope

Tr ig ge ri ng

Triggering
The default trigger type is auto, which means the oscilloscope will trigger after 100 milliseconds. The trigger appears in the center of the acquisition. You can change where the trigger is in the data set by using the Delay field.
To specify more complicated triggers, select the Trig g e r... button at the bottom of the main oscilloscope window. This brings up the Trigger Setup Window.
You can also display the Trigger Setup window by selecting the trigger marker and choosing Tri g g e r... from the menu.
The area to the right of the Trigger button indicates the current trigger. It does not show details such as occurence count.
•“Trigger Concepts” on page 38
•“Edge Triggering” on page 40
•“Pattern Triggering” on page 41
•“Delayed Triggering” on page 42
•“Getting a Stable Trigger” on page 43
•“The Trigger Setup Window” on page 44
Trigger Concepts
Trigger B a s ics
The scope trigger circuitry helps you locate the waveform you want to view. There are several types of triggering, but the one that is used most often is edge triggering. Edge triggering identifies a trigger condition by looking for the slope (rising or falling) and voltage level
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Trig ge ri ng
(trigger level) on the source you select. The trigger source is restricted to channel 1, channel 2, and the external trigger. If you have more channels on your oscilloscope, they cannot be used as trigger sources.
This figure shows the trigger circuit diagram.
Your waveform enters the positive input to the trigger comparator where it is compared to the trigger level voltage on the other input. The trigger comparator has a rising edge and a falling edge output. When a rising edge of your waveform crosses the trigger level, the rising edge comparator output goes high and the falling edge output goes low. When a falling edge of your waveform crosses the trigger level, the rising edge output goes low and the falling edge output goes high. The scope uses the output you have selected as the trigger output.
Aliasing and Triggering
While aliasing does not cause unstable triggering, it does make it difficult to tell when the scope is triggered. An aliased waveform can appear as a lower frequency waveform that drifts across the display. To ensure that your waveform is not aliased, you should decrease the horizontal scale to its minimum value (maximum sampling rate), then increase it to view your waveform.
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Tr ig ge ri ng
Edge Triggering
Edge trigger is the default trigger setting. Edge mode sets the oscilloscope to trigger on an edge. You can set the source, trigger level, and slope in the oscilloscope main window. Selcting the Trigger... button brings up the Trigger Setup window, which lets you set the number of edges.
You can also display the Trigger Setup window by selecting the trigger marker and choosing Tri g g e r... from the menu.
The oscilloscope identifies an edge trigger by looking for the specified slope (rising edge or falling edge) of your waveform. Once the slope is found, the oscilloscope will trigger when your waveform crosses the trigger level.
If you set the source to External, the trigger level is fixed at -1.30 V.
NOTE: The oscilloscope always fills a certain amount of acquisition memory before
looking for a trigger. When counting edge occurrences, you may see more edges before the trigger than the number you specified. This happens because some edges were already in memory but are not included in the occurrence count.
When you set the trigger level on your waveform, it is usually best to set it to a voltage near the middle of your waveform. The middle range is best because there may be ringing or noise at the high and low ends which can cause false triggers.
When you adjust the arm level control, a horizontal dashed line with a T on the right-hand side appears, showing you where the arm level is with respect to your waveform. After a period of time the dashed line will disappear. You can get the line back by adjusting the arm level control again.
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Trig ge ri ng
Pattern Triggering
Pattern triggering is similar to the way that a logic analyzer captures data. This mode is useful when you are looking for a particular set of ones and zeros on a computer bus or control lines. You can use channel 1 and 2 and the external trigger to form the trigger pattern. Because you can set the voltage level that determines a logic 1 or a logic 0, any logic family that you are probing can be captured. Channels 3 through 8, available in multi-board oscilloscopes, cannot be used in the pattern.
You can display the Trigger Setup window by selecting the trigger marker and choosing Tri g g e r... from the menu.
When Pattern
There are five ways you can use to further qualify the pattern that you want to view. They are:
Entered When the scope finds the pattern, it triggers on the edge of
the pulse that makes the pattern valid.
Exited The scope arms the trigger circuitry when it has found the
pattern and triggers on the edge of the pulse that ends the pattern.
Present > The scope triggers when the pattern is found and is present
for greater than the time value that you specify.
Present < The scope triggers when the pattern is found and is present
for less than the time value that you specify.
Range > The scope triggers when the pattern is present within the
time range that you specify.
NOTE: For Present >, Present <, and Range >, the oscilloscope does not trigger until
the pattern is exited.
1. Set up a pattern by selecting the X button after each channel name.
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Tr ig ge ri ng
X means the channel is not part of the pattern. Low and High let you set the threshold voltages for channel 1 and channel
2.
2. Select the When Pattern that you want.
3. If you have selected Present >, Present <, or Range >, set the time values. The minimum is 20 ns, and the maximum is 160 milliseconds.
4. Close the Trigger Setup dialog box.
The area to the right of Trigger... shows the pattern you set up.
Delayed Triggering
You can delay the trigger by setting the Delay field. The Delay field changes the acquisiton delay. Acquisition delay is the amount of time between the trigger event and the center of the acquisition. It is the only way to change the pre-trigger and post-trigger amounts in the Agilent Technologies 16533A or 16534A Digitizing Oscilloscope.
To Store Mostly Post­Trigger Data
The value shown in the Delay field is the sum of the acquisition delay and the display delay. The display delay is controlled by the scrollbar, and indicates which portion of the acquisition is currently being displayed.
1. Calculate 16,350 (about half the acquisition memory) divided by the sample rate. You should get a value in seconds.
2. Enter that value in the delay field. Use n for nanoseconds, u for microseconds, and m for milliseconds.
3. If the value is correct, the scrollbar will move to one end of its range and the current signal will not cross the entire display.
4. Select the Run button. The scrollbar returns to the middle. If you adjust the scrollbar before seleing the Run button, the oscilloscope treats the value as a display delay only.
To store mostly pre-trigger data, calculate the same value and enter it as a negative number.
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Trig ge ri ng
To Re-center the Trigger in the Acquisition
See Also Vertical and Horizontal Scaling on page 52
1. Drag the scrollbar to the center of the scroll area. There is a slight delay in movement when the bar is at the center.
2. Set Delay at the bottom of the window to 0 seconds, and press enter. The scrollbar may jump away from the center. Do not reset it.
3. Select the Run button to get a new acquisition.
Getting a Stable Trigger
For most waveforms, the easiest way for you to get a stable trigger is to use Autoscale. Autoscale analyzes your waveform and sets the trigger mode to edge and the vertical scale, horizontal scale, and trigger level to best display your waveform.
Manual Triggering
While Autoscale is the easiest way to obtain a stable trigger, there are times when you may need to set the trigger manually to capture more complex waveforms. To stabilize these waveforms:
Set the Trigger Level to the proper point on the waveform. The proper point is usually somewhere around 50% to avoid possible ringing and noise at the top and base voltages.
Increase the sampling rate to avoid aliasing. The sampling rate is controlled by the horizontal scale at the bottom of the screen. The maximum sampling rates are 1 gigasample per second for the 16533A and 2 gigasamples per second for the 16534A.
Set the Trigger Sweep to Triggered for low-frequency waveforms. The Trigger Sweep field is in the Trigger Setup dialog.
Remove noise from your waveform.
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Tr ig ge ri ng
You can display the Trigger Setup window by selecing the trigger marker and choosing Tri g g e r... from the menu.
See Also The Trigger Setup Window on page 44
Autoscale on page 32
Changing the Sample Rate” on page 54
The Trigger Setup Window
The Trigger Setup window is for setting up complex triggers. You access it by selecting the Trig g e r... button at the bottom of the main oscilloscope window.
The two selections that are always availabe in the window are Mode and Sweep. Mode specifies the type of condition you want to trigger on. Sweep indicates whether the oscilloscope should wait for the condition (Tri ggered) or trigger immediately if the condition doesn’t show up in 100 milliseconds (Auto).
Edge
Pattern
Edge mode sets the oscilloscope to trigger on an edge. You can specify the source, trigger level, slope, and occurrence.
The oscilloscope identifies an edge trigger by looking for the specified slope (rising edge or falling edge) of your waveform. Once the slope is found, the oscilloscope will trigger when your waveform crosses the trigger level.
If you set the source to External, the trigger level is fixed at -1.30 V.
Use pattern mode for triggering on glitches or unusually long pulses, or for a trigger involving 2 channels.
To Trigger on a Glitch
1. Select the Tr i g ger.. . button.
2. Set the mode to Pattern and the sweep to Triggered.
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Trig ge ri ng
3. Specify the glitch source by setting it to high or low. An X means the channel is not part of the pattern.
4. Select the option button under When Pattern and choose Present <.
5. Set the duration field to less than your clocks pulse width.
Immediate
Use immediate mode when the oscilloscope is triggered by another instrument in the measurement, or to acquire data as soon as you select the Run button. No other levels or settings may be specified for this mode.
You can also display the Trigger Setup window by selecting the trigger marker and choosing Tri g g e r... from the menu.
See Also Edge Triggering” on page 40
Pattern Triggering” on page 41
Trigger Concepts on page 38
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Changing Waveform Display and Grid

Changing Waveform Display and Grid
•“Zooming In” on page 46
•“Changing the Persistence of the Waveform” on page 46
•“Viewing Noisy Waveforms with Averaging” on page 48
•“Changing Display Colors” on page 50
•“Changing the Grid” on page 50
Zooming In
To zoom in on a particular area of your waveform, drag a selection rectangle over the area and release.
To undo zoom, select in the display area and choose Undo Zoom. You can also choose Undo Zoom from the Setup menu.
Zoom may change your vertical scale (V/div), offset value, horizontal scale (timebase or s/div), and scrollbar position to match the current section of the waveform as though you had acquired it in that state. When the new settings exceed limits, the display change does not occur. This is most likely to happen with extreme negative delays and detailed vertical scaling (V/div). You may be able to zoom in if you enclose a larger area in the zoom.
If you Run then Undo Zoom, the original settings will be restored, but your waveform may look wrong. The gaps are due to clipping; the Agilent Technologies 16533A or 16534A oscilloscopes treat clipped data by leaving it at the top and bottom edges of the display.
Changing the Persistence of the Waveform
Normally, a waveform is displayed only for one acquisition. When the next run occurs, the previous waveform is erased and the newly
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Changing Waveform Display and Grid
acquired waveform is drawn on the display.
By using accumulate, you can see a visual history of a waveform’s acquisitions over time. For example, you can see the accumulated peak-to-peak noise of a waveform over time which may appear significantly different than in only one acquisition. You can see timing jitter, the variance of the waveform from the trigger event, by accumulating acquisitions on the display. By using accumulate, viewing a waveforms extremes over time is much easier.
Waveform mode sets the amount of time a waveform sample appears on the display. Automated measurements cannot be performed on accumulated waveforms but will be performed on the most recent waveform in acquisition memory. Waveform accumulation does not occur beyond the display area boundary.
The Agilent Technologies 16533A or 16534A Digitizing Oscilloscope have three waveform modes: Normal, Accumulate, and Average.
Normal
In the normal waveform mode, a waveform data point is displayed for at least 10 ms or one trigger cycle then erased. If no further triggers occur, the last acquisition is left on the display. This is the default setting. Use this mode for the fastest display update rate.
Accumulate
Accumulate is most like infinite persistence. In the accumulate waveform mode, a waveform sample point is displayed until settings are changed. All sample points are shown at full intensity. Use accumulate to measure jitter or eye diagrams, see a waveform’s envelope, look for timing violations, and find infrequent events.
Average
When Averaging is enabled, the # Avgs control tells the oscilloscope the number of waveforms you want to use in calculating the average value for each sample point. The Agilent Technologies 16533A or 16534A oscilloscopes can average from 2 to 512 waveform acquisitions but the larger the number of acquisitions, the more time it will take to accumulate all the waveforms you have requested.
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Changing Waveform Display and Grid
NOTE: If you are using Accumulate or Average and you change the vertical or
horizontal scaling, position, offset, trigger source or level, zoom, or drag the waveform then the display is redrawn and any accumulated waveforms are cleared. Only the last acquisition is displayed.
Set up markers and any measurements before using accumulate or averaging. Adding markers or clearing measurements later can erase acquired waveforms.
See Also Viewing Noisy Waveforms with Averaging on page 48
Display Setup Window on page 59
Viewing Noisy Waveforms with Averaging
The Waveform Average mode under Display tells the oscilloscope to acquire waveforms from several acquisitions and average them all together, point by point. The greater the number of averages, the less impact each new waveform has on the composite averaged waveform. The perceived display update rate is slowed down as the number of averages is increased because the averaged waveform doesnt change as much.
Sometimes, a waveform consists of a signal along with some random or asynchronous noise. By using Waveform Average, these noise sources can average to zero over time while the underlying waveform is preserved. This will improve the accuracy of waveform measurements because measurements are made on a more stable waveform and measurement variances are reduced. The effective resolution of the displayed waveform also improves as more acquisitions are averaged together, providing the input waveform is repetitive and has a stable trigger point.
Incidentally, if Waveform Average is enabled but the scope is not properly triggering (perhaps the scope is set to Auto trigger and the wrong trigger channel is selected), you may not see the waveform you expect on the display. In this case, the input waveform is asynchronous to the scope and will average to zero over time even though a non-zero
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input waveform is being measured.
When Waveform Average is enabled, the # Avgs control sets the number of waveforms you want to use in calculating the average value for each sample point. The Agilent Technologies 16533A or 16534A can average from 2 to 512 waveform acquisitions but the larger the number of acquisitions, the more time it will take to accumulate all the waveforms you have requested.
The following formula is used to calculate the average for each data point:
For n between 1 and M. After terminal count is reached (n greater than or equal to M),
where:
= the average sample value
Ave
n
n = the current average number M = setting of # Avgs control (terminal count)
= the ith sample.
S
i
See Also Changing the Persistence of the Waveform on page 46
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Chapter 1: Agilent Technologies 16533/34A Digitizing Oscilloscope
Changing Waveform Display and Grid
Trigger Concepts” on page 38
Getting a Stable Trigger on page 43
Changing Display Colors
The display colors which indicate channels, memories, and markers are editable. These colors are also used by the display tools in the rest of the logic analysis system.
To Change Colors
1. In the menu bar, select Setup.
2. Select Display... The Display Setup dialog appears.
3. Under Colors, select the channel to modify.
4. Select the color you want it to be.
5. Select the Edit Colors... button to change a color's value.
NOTE: If you Close the Color Edit box, the new color values will be used in this
session only. If you Apply the color values, they will be used in this session
and following sessions. To restore the factory colors, select the Reset Defaults button.
Changing the Grid
The Agilent Technologies 16533A or 16534A Digitizing Oscilloscope has a 10 by 8 display graticule grid which you can turn on or off. When on, a grid line is place on each vertical and horizontal division. When the grid is off, a frame with tic marks surrounds the graticule edges.
You can dim the grids intensity or turn the grid off to better view waveforms which the graticule lines might obscure. Otherwise, you can use the grid to estimate waveform measurements such as amplitude and period. The grid intensity control doesnt affect printing. You must
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explicitly turn the grid off to remove the grid from a hardcopy.
1. In the menu bar, select Setup.
2. Select Display... The Display Setup dialog appears.
3. Select the Grid Type option button to change the grid to axes-only scales, frame-only scale, or a background grid. The intensity field controls the brightness. You cannot change the grid color.
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Vertical and Horizontal Scaling

Vertical and Horizontal Scaling
The vertical scale is volts per division (V/div). Changing the vertical scale affects the height of the waveform. Extreme changes to the vertical scale can affect your offset values. If the waveform extends beyond the top or bottom of the display, data will be clipped. You cannot measure clipped data, and when you adjust the offset or vertical scale, clipped data stays at the top or bottom edge with a break in the waveform.
The horizontal scale is seconds per division (s/div). Changing the horizontal scale compresses and expands a waveform, and changes the sampling rate. The automatic measurements only measure what is currently shown in the display window, however.
Compressing the waveform may cause your sample rate to slow down. Similarly, expanding your waveform may cause your sample rate to increase, up to 1 gigasample per second for the 16533A or 2 gigasamples per second for the 16534A. See the table in Changing the Sample Rate on page 54 for timebase and sampling rates.
The vertical (V/div) scale control is located under the Channels tab. The horizontal (s/div) scale control is located at the bottom left corner of the oscilloscope window.
Scrolling
The scrollbar below the display indicates what portion of the current data set you are viewing. Its size shows the percentage of the data you are looking at, and its location indicates the location of the data within the data set.
You can scroll through your data set by dragging the scrollbar. You can also use the Delay field, but this may change your acquisition delay as described in Delayed Triggering on page 42.
To scroll short distances, drag the waveforms or trigger reference marker. Individual waveforms can also be dragged vertically. Dragging waveforms does change the delay and offset fields and will affect your next acquisition.
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When you select the Run button after having moved the scrollbar, the display shows the same section of the data set that you were viewing before. For example, if you had the scrollbar at the right end, you were viewing the last part of the data set. When you select the Run button, the oscilloscope acquires more data and again displays the last portion.
Sometimes you may not be able to move the scrollbar through the entire scrolling area. This is because you have increased the sample rate. The scrolling area indicates the size of the next acquisition, but you can only move the scrollbar through the area filled with the current data set. You can use the Delay arrows to move the scrollbar past its dragging limits.
See Also Delayed Triggering on page 42
Changing the Sample Rate” on page 54
Channel Setup Window on page 33
Vertical and Horizontal Scaling
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Changing the Sample Rate

Changing the Sample Rate
The s/div scale controls the sample rate. The relationship is shown in a table at the end of this topic.
The sample rate is displayed in the bottom left corner of the display area. The maximum sample rate is 1 gigasamples per second for the 16533A and 2 gigasamples per second for the 16534A. The minimum sample rate is 500 samples per second.
Aliasing
Aliasing occurs when the sample rate is not at least four times as fast as the high frequencies of your waveform. If you cannot see why the oscilloscope triggered, or if the waveform moves around on screen, or if the waveform looks slower than it should, suspect aliasing. To increase your sample rate, set the s/div scale to a higher number, then run again.
See Also “Trigger Concepts” on page 38
s/div Sample Rate
< 200 ns 2 GSa/s
500 ns 1 GSa/s
1 us 500 MSa/s
2 us 250 MSa/s
5 us 100 MSa/s
10 us 50 MSa/s
20 us 25 MSa/s
50 us 10 MSa/s
100 us 5 MSa/s
200 us 2.5 MSa/s
500 us 1 MSa/s
1 ms 500 KSa/s
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2 ms 250 KSa/s
5 ms - 20 ms 100 KSa/s
50 ms 50 KSa/s
100 ms 25 KSa/s
200 ms 10 KSa/s
500 ms 5 KSa/s
1 s 2.5 KSa/s
2 s 1 KSa/s
5 s 500 Sa/s
Changing the Sample Rate
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Comparing Channels

Comparing Channels
The Agilent Technologies 16533A or 16534A Digitizing Oscilloscope do not support waveform math (A+B or A-B). However, you can easily
overlay waveforms by putting the 0 V indicators ( ) on top of each other, and making sure the waveforms have the same scale. The automatic measurements are done on only one waveform, however.
Using waveform memories, you can also compare a waveform from a previous acquisition to the current display. The waveform must be loaded into memory when it is captured. The captured waveform can be displayed either with the current scale settings or with the ones used when it was captured.
See Also Using Markers on page 75
Using Waveform Memories on page 78
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What Do the Display Symbols Mean?

What Do the Display Symbols Mean?
All the indicators around the edge of the grid are draggable.
Local voltage marker. The color indicates which channel it is measuring.
Local time marker. Time markers are channel independent.
Trigger event indicator.
Global marker. The global markers measure time and retain their position within the total acquisition of all instruments in a Group Run.
Trigger level indicator. The color indicates which channel it is set on.
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What Do the Display Symbols Mean?
0 V (ground) indicator. The color indicates which channel it is set on. The 0 V indicator is controlled by the offset setting. When offset is negative, the 0 V indicator is above the center line. When offset is positive, the 0 V indicator is below the center line. Also referred to as offset indicator.
Offscreen indicator. The color indicates which channel it is set on. The offscreen indicator appears when the 0 V indicator moves offscreen.
See Also Using Markers on page 75
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Display Setup Window

Display Setup Window
The settings under Display control how waveforms are displayed. Only "Acquisition Memory to Display" affects acquisitions.
Waveform Mode
Normal
Accumulate draws subsequent waveforms in the same area, without
is the default setting. It shows the current acquisition only.
erasing previous waveforms. The accumulated waveforms are erased if any settings are changed, however.
Average averages the current acquisition with the specified number of
prior acquisitions. All acquisitions are equally weighted. The averaged waveforms are replaced with the current acquisition if any settings are changed.
Acquisition Memory to Display
For lower time resolutions, these settings allow you to optimize the oscilloscope for greater detail or longer duration. All gives greater detail by sampling more frequently. Partial stretches the acquisition memory over a longer duration by slowing down the sample rate. These settings do not make a difference when the horizontal scale is finer than 1.00 microsecond/division for a 16533A, or 500 nanoseconds/ division for a 16534A.
Setup...
The Setup... button opens the Display Setup window. This window contains the same controls under the Display tab, and also lets you change the graticule and waveform colors.
Clear Display
The Clear Display button removes all channels from the graticule. It does not affect waveform memories or markers.
See Also Changing the Persistence of the Waveform on page 46
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Display Setup Window
Changing Display Colors on page 50
Changing the Grid on page 50
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Automatic Measurements and Algorithms

Automatic Measurements and Algorithms
Automatic measurements are simpler and usually more accurate to make than the corresponding measurement done manually. (Manual measurements and simple statistics are done using markers; see “Using Markers on page 75.) Blank values in the automatic measurement field means that requirements for that measurement were not met. For specific measurements, see the list below.
•“How the Scope Makes Measurements” on page 62
•“Average Voltage (Vavg)” on page 63
•“Base Voltage (Vbase)” on page 66
•“Fall Time” on page 64
•“Frequency” on page 65
•“Maximum Voltage (Vmax)” on page 69
•“Minimum Voltage (Vmin)” on page 69
•“Negative and Positive Pulse Width (±Width)” on page 64
•“Overshoot” on page 68
•“Peak-to-Peak Voltage (Vpp)” on page 68
•“Period” on page 63
•“Preshoot” on page 67
•“Rise Time” on page 63
•“Time of Maximum Voltage (Tmax)” on page 70
•“Time of Minimum Voltage (Tmin)” on page 70
•“Top Voltage (Vtop)” on page 66
•“Voltage Amplitude (Vamp)” on page 70
•“Vdcrms (Root Mean Square Voltage, DC)” on page 71
See Also About the Measurements on page 71
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Increasing the Accuracy of Your Measurements” on page 73
Autoscale on page 32
How the Scope Makes Measurements
Automatic parametric measurements are calculated from a histogram. Measurements are done as soon as valid data is available. The absolute minimum and maximum are derived from the histogram.
Next, the statistical top and base values are calculated. The top 40% of the histogram is scanned for the top value and the bottom 40% is scanned for the base value. The center 20% of the histogram is not scanned to prevent selecting the middle of a tri-state waveform.
The measurement algorithm decides whether the absolute maximum and minimum values should be used, as in the case of triangle waveforms, or the statistical top and base should be used, as in the case of square waveforms.
After the top and base are calculated, the IEEE 10%, 50%, and 90% thresholds are calculated. These thresholds determine edges and are used by all timing measurements. For example, rise time is measured from the lower threshold to the 90% threshold of a rising edge. Period, frequency, and pulse width measurements use the 50% threshold.
Once the thresholds have been calculated, the edges can be determined. A rising edge is defined as a transition that passes through the 10%, 50%, and 90% threshold levels. A falling edge is defined as a transition that passes through the 90%, 50%, and 10% threshold levels. For an edge to be detected, it must complete the transition through all
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three threshold levels.
Once the oscilloscope locates rising and falling edges, it calculates rise time, fall time, and frequency. If too few sample points fall along an edge, the measurement is not made. The oscilloscope ignores incomplete transitions.
Average Voltage (Vavg)
Vavg is the average voltage of waveform data over the display. It does not include data that is offscreen. The value is calculated by summing all the data points on the screen and dividing by the number of them.
Period
Period is defined as the time between the 50% threshold crossings of two consecutive, like-polarity edges.
The Agilent Technologies 16533A or 16534A Digitizing Oscilloscope starts the measurement at the leftmost edge of the display.
Rise Time
Rise time is defined as the time at the 90% threshold minus the time at the 10% threshold on the edge you are measuring.
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The Agilent Technologies 16533A or 16534A Digitizing Oscilloscope starts the measurement at the leftmost edge of the display.
Fall Time
Fall time is defined as the time at the 10% threshold minus the time at the 90% threshold on the edge you are measuring.
The Agilent Technologies 16533A or 16534A Digitizing Oscilloscope starts the measurement at the leftmost edge of the display.
Negative and Positive Pulse Width (±Width)
Negative pulse width is defined as the time from the 50% threshold of the first falling edge to the 50% threshold of the next rising edge.
Positive pulse width is defined as the time from the 50% threshold of the first rising edge to the 50% threshold of the next falling edge.
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Negative Pulse Width
Automatic Measurements and Algorithms
Positive Pulse Width
The Agilent Technologies 16533A or 16534A Digitizing Oscilloscope starts the measurement at the leftmost edge of the display.
Frequency
Frequency is defined as 1/Period. Period is the time between the 50% threshold crossings of two consecutive, like-polarity edges.
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The Agilent Technologies 16533A or 16534A Digitizing Oscilloscope starts the measurement on the first edge of the leftmost portion of the display.
Base Voltage (Vbase)
Vbase is the voltage of the statistical minimum level of the waveform display, which is defined as the most frequently occurring voltage in the histogram of the bottom 40% of the waveform.
Vbase may be equal to Vmin for many waveforms, such as triangle waveforms. Similarly, Vtop may be equal to Vmax.
This measurement is position-independent and the entire display is used for the measurement.
Top Voltage (Vtop)
Vtop is the voltage of the statistical maximum level of the waveform
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display, which is defined as the most frequently occurring voltage in the histogram of the top 40% of the waveform.
Vtop may be equal to Vmax for many waveforms, such as triangle waveforms. Similarly, Vbase may be equal to Vmin.
This measurement is position-independent and the entire display is used for the measurement.
Preshoot
Preshoot is a waveform distortion that precedes an edge transition.
If the edge is rising, preshoot will be 100*(base - local minimum)/ (top
- base). The local minimum is found half way from the 10% threshold
level to the 10% threshold level at the previous falling edge.
If the edge is falling, preshoot will be 100*(local maximum - top)/(top ­base). The local maximum is found half way from the 90% threshold level to the previous 90% threshold level at the previous rising edge.
The Agilent Technologies 16533A or 16534A Digitizing Oscilloscope starts the measurement at the first edge of the leftmost portion of the
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display.
Overshoot
Overshoot is a waveform distortion that follows a major edge transition.
If the edge is rising, the overshoot will be 100*(local maximum - top)/ (top - base). The local maximum is found half way from the 90% threshold level to the next 90% threshold level at the falling edge.
If the edge is falling, the overshoot will be 100*(base - local minimum)/ (top - base). The local minimum is found half way from the 10% threshold level to the next 10% threshold level at the next rising edge.
The Agilent Technologies 16533A or 16534A Digitizing Oscilloscope starts the measurement at the first edge on the leftmost portion of the display.
Peak-to-Peak Voltage (Vpp)
Peak-to-peak voltage is defined as Vmax - Vmin. Vmax is the absolute maximum voltage of the display. Vmin is the absolute minimum voltage of the display.
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This measurement is position-independent and the entire display is used for the measurement.
Minimum Voltage (Vmin)
Vmin is the absolute minimum voltage of the waveform display.
This measurement is position-independent and the entire display is used for the measurement.
Maximum Voltage (Vmax)
Vmax is the absolute maximum voltage of the waveform display.
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This measurement is position-independent and the entire display is used for the measurement.
Time of Minimum Voltage (Tmin)
Tmin is the first time that the minimum voltage occurs on the display.
This measurement is position-independent and the entire display is used for the measurement.
Time of Maximum Voltage (Tmax)
Tmax is the first time that the maximum voltage occurs on the display.
This measurement is position-independent and the entire display is used for the measurement.
Voltage Amplitude (Vamp)
Vamp is the amplitude of the waveform display. Vamp = Vtop - Vbase.
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This measurement is position-independent and the entire display is used for the measurement.
Vdcrms (Root Mean Square Voltage, DC)
Vdcrms is the root-mean-square voltage of the waveform. The equation used is:
This measurement is position-independent and the entire display is used for the measurement. Data points offscreen are not included.
About the Measurements
The Agilent Technologies 16533A or 16534A Digitizing Oscilloscope makes measurements after every trigger event, always maintaining continuity between the measurement results and the oscilloscope display. This makes sure that no aberration in the waveform under observation is missed.
If the waveform is clipped, the oscilloscope cannot make some automatic measurements. These measurements will show clipped where a value would normally appear. Other indicators you may see are:
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? Value is questionable. This can occur because the signal is
clipped, there are not enough points, or the amplitude is too small.
< The result is less than or equal to the value shown. This can
occur when the waveform is clipped low or not enough points are available.
> The result is greater than or equal to the value shown. This
can occur when the waveform is clipped high or not enough points are available.
(blank) No value could be calculated. The most common reason is
missing edges, such as when the display shows less than a full period of a waveform.
The Agilent Technologies 16533A or 16534A will interpolate sample points if necessary to determine pulse parameters for automatic measurements. Excessive interpolation can lead to jitter on measurements; if this occurs you may have to increase the sample rate.
By default, the oscilloscope uses the IEEE thresholds of 10, 50, and 90 percent for pulse measurements. A rising or falling edge is only recognized after passing through all three thresholds. These thresholds appear on the example pulse waveform as shown below:
Period and Frequency Measurements
At least one full cycle of the waveform with at least two like edges must be displayed for period and frequency measurements. Automatic waveform measurements use a single pulse and may have significant errors introduced by interpolation and trigger inaccuracies. The leftmost cycle is used for making measurements.
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Pulse Width Measurements
For either the -Width or +Width measurements, a complete pulse must be displayed to make a valid measurement. Remember that an edge must pass through all three thresholds to be recognized as an edge. Therefore, it is important that the pulse be positioned so that both pulse edges transition through all three thresholds and are displayed on the screen. Pulse width is measured from the leftmost valid edge to the next valid edge.
Rise Time, Fall Time, Preshoot, and Overshoot Measurements
The leading, rising edge of the waveform must be displayed for rise time and rising edge preshoot and overshoot measurements. The trailing, falling edge of the waveform must be displayed for fall time and falling edge preshoot and overshoot measurements. The leftmost edge is used for measurements.
Remember that an edge must pass through all three thresholds to be recognized as an edge. Therefore, it is important that the pulse be positioned so that all three thresholds are displayed on the screen. Rise time, fall time, preshoot, and overshoot measurements will be more accurate if you expand the edge of the waveform by choosing a faster sweep speed. Expanding the waveform will provide more data points on an edge, reduce interpolation, and thus provide a more accurate measurement.
Increasing the Accuracy of Your Measurements
Things you can do to make your measurements more accurate:
Deskew the oscilloscope channels. To deskew the oscilloscope channels, perform the Channel Skew procedure as part of calibrating the oscilloscope (see page 10).
Use automatic measurements where possible.
For positive and negative pulse width, make sure enough top and bottom
voltages are showing to accurately calculate the top and base voltages.
When using markers, increase the sampling rate.
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Minimize the effect of DC errors on time measurements by
measuring between identical edges (same slew rate, amplitude and
offset).
using the same DC level to reference each endpoint of the interval.
performing the measurement on the fastest-slewing portion of each
edge.
making the waveform as large as possible.
Calibrate (see page 10) your oscilloscope after it has warmed up.
See Also Getting a Stable Trigger on page 43
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Using Markers

Using Markers
The Agilent Technologies 16533A or 16534A Digitizing Oscilloscope has both local and global markers. The local markers can only be used within the oscilloscope window. The global markers retain their position across the data sets of all instruments that are part of the same group run as the oscilloscope.
The global markers are G1 and G2 and only measure time. The local markers consist of four voltage markers, V1 - V4, and two time markers, T1 and T2.
To access the markers, select the Markers tab then select the Setup... button. The Marker Setup dialog appears, from which you can turn on any of the markers by selecting the appropriate button. From this dialog, you can also change the channel of the voltage markers.
The information after this does not apply to automatic time markers. Those are covered in a separate topic listed below.
When the markers are turned on, you can set their values by dragging them. If a marker moves offscreen because of scrolling or from typing in a value in the Marker Setup window, you can return it to the edge of the display by selecting the arrow buttons in the Marker Setup window.
You can also place markers by selecting the area you want the marker on and choosing Place Marker and the marker you want from the menu. If your cursor is on a marker already, select Markers... to display the Marker Setup dialog.
See Also What Do the Display Symbols Mean?” on page 57
About Automatic Time Markers on page 76
Working with Global Markers in Correlated Displays (see the Markers help volume)
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Using Markers
About Automatic Time Markers
Automatic time markers indicate the time at which a specified voltage crossing occurs. For instance, if you scroll the display, an automatic time marker defined for the third edge will automatically reposition itself on the edge third from the left. A regular time marker would remain placed on the waveform and scroll with it off the display.
When you turn on an automatic time marker, Min T2-T1, Max T2-T1, and Mean T2-T1 appear at the bottom of the Markers area. You can gather statistics as long as both time markers are on, and one is an automatic marker. Changing any part of the display will clear statistics.
To turn on automatic time markers
1. Under the Markers tab, select the Setup... button.
2. Select the time marker button.
3. Choose Marker [OFF] to turn on the marker.
4. Choose Automatic [OFF] to put it in automatic mode.
5. Select the Define Automatic Marker... button. If you did not put the marker in automatic mode, the area to the right of T1 or T2 is a time from trigger setting.
6. Specify the automatic setting. Percentage level is based on the automatically calculated top and base voltage.
Automatic time markers cannot be dragged when they are on their specified edge. If the specified edge does not exist, they can be dragged like regular time markers.
See Also Top Voltage (Vtop)” on page 66
Base Voltage (Vbase)” on page 66
How the Scope Makes Measurements on page 62
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Differences from a Standard Digitizing Oscilloscope

Differences from a Standard Digitizing Oscilloscope
There are some differences between an Agilent Technologies 16533A or 16534A Digitizing Oscilloscope and a standard stand-alone digitizing oscilloscope.
Clipped data (data that is offscreen at acquisition) stays at the top or bottom edge of the display area when the clipped waveform is resized or has the offset moved. The waveform appears to have a gap in it where the clipped data was.
Repetitive run is repetitive real-time acquisitions, not what is also referred to as equivalent-time mode.
When there are not enough data points to map at least one sample to each column of pixels in the display, the sin(x)/x interpolation filter is on. You cannot turn it off.
There is only one graticule area. All oscilloscope channels are sampled and displayed at the same rate.
The Agilent Technologies 16533A or 16534A oscilloscope is easier to use in conjunction with a logic analyzer because arming is handled by the Agilent Technologies 16700A/B-series frame. You do not need to connect any wires between the two modules.
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Using Waveform Memories

Using Waveform Memories
The four waveform memories store copies of waveforms for display within the oscilloscope tool. The memories cannot be exported to other display tools.
To Use Waveform Memory
This procedure assumes you already have acquired a waveform that you want to store.
1. Under the Memories tab, select the Setup... button.
2. In the Load Waveform area, select the waveform source. The button text depends on your setup, but the default is channel 1.
3. Select the Load button. Sources can be any channel or another waveform memory. If the source does not contain any data (for example, the channel was off during the last acquisition), "Waveform data is not valid!" appears briefly at the top of the Waveform Memory Setup window. If the display is set to accumulate or average, only the last acquired waveform is loaded.
4. To view the memory, select the Off radio button.
5. To make the memory display independent of the main display controls, select the box to the left of Horizontal. This enables the independent horizontal scale controls.
Waveform memories are erased between sessions. They are not cleared when the display is cleared. In all other ways, waveform memories are treated like channels by the display functions.
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Loading and Saving Oscilloscope Configurations

Loading and Saving Oscilloscope Configurations
Oscilloscope settings and data can be saved to a configuration file. You can also save any tools connected to the oscilloscope. Later, you can restore your data and settings by loading the configuration file into the oscilloscope.
Loading Configuration Files (see the Agilent Technologies 16700A/B- Series Logic Analysis System help volume)
Saving Configuration Files (see the Agilent Technologies 16700A/B- Series Logic Analysis System help volume)
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When Something Goes Wrong

When Something Goes Wrong
•“Error Messages” on page 80
•“Calibration Problems” on page 80
•“Triggering Problems” on page 80
•“Other Problems” on page 81
Error Messages
No valid signals have been found. (see page 82)
Incorrect Calibration Factors for this software revision. (see page 83)
Waiting for IMB Arm. (see page 83)
Calibration Problems
Calibration is not possible because NV RAM is protected
Unprotect the NV RAM and try again.
Calibration Procedure did not complete successfully
The Calibration window shows which tests passed and failed. If any test failed and all cables were correctly hooked up, you should contact your Agilent Technologies Service Center.
Triggering Problems
Scope loses trigger when changes made to offset
The trigger level may be too high or too low to reliably trigger before autotrigger. Sometimes this over-sensitivity to offset is caused by too
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When Something Goes Wrong
high an attenuation factor in the channel setup.
Low frequency waveform appears to have unstable trigger
See Getting a Stable Trigger on page 43.
Nothing happening
If the scope is being triggered by another instrument, and you were changing some settings, the scope may have missed its trigger signal.
The other common causes when the trigger is set to Triggered are
trigger level occurs outside normal signal
the oscilloscope is waiting for a rare event
You can either stop the oscilloscope or set the trigger to Auto to look for these conditions.
Other Problems
Autoscale failed to find a waveform
Check that either channel 1 or channel 2 is on. Autoscale autoscales all channels, but can only trigger on channel 1 or 2.
Also check for correct channel setup. The wrong setup can attenuate a proper signal into an apparent DC signal.
Waveform has gaps when offset is changed or V/div increased
If a waveform is clipped, when you move the offset the clipped portion of the waveform will stay at the top or bottom of the display, with a break in the rest of the waveform. This also happens if you increase V/ div so that more of the waveform fits in the display. Those portions that were off the display during acquisition contain uncertain data and so are not displayable.
To get good data, make the changes to your settings and run again.
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When Something Goes Wrong
Trigger won’t return to center
The trigger delay is affected by both the scrollbar position and the value in the delay field. To re-center the trigger in the acquisition,
1. Drag the scrollbar to the center of the scroll area. There is a slight delay in movement when the bar is at the center.
2. Set Delay at the bottom of the window to 0 seconds, and press enter. The scrollbar may jump away from the center. Do not reset it.
3. Select the Run button to get a new acquisition.
The trigger is now in the center of the acquisition as well as the display window.
Scope keeps stopping
The Agilent Technologies 16533A or 16534A Digitizing Oscilloscope default to single-shot acquisition. To have the oscilloscope keep running, select the Run Repetitive button.
NOTE: The Agilent Technologies 16533A or 16534A Digitizing Oscilloscope does not
do equivalent-time sampling. All runs in the repetitive run mode are single acquisitions.
Scope locked up
The logic analysis system may be busy. Wait a few minutes and try again. If the problem persists, exit the session and cycle power on the frame.
If you can find a sequence of steps that always or frequently causes this to happen, please contact the Agilent Technologies Sales Office to report this bug.
Error Message: No Valid Signals
This message only comes up when autoscale is run and the oscilloscope is unable to detect any line activity. Possible causes are:
No channels are turned on. Autoscale does not check channels that are turned off.
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When Something Goes Wrong
The oscilloscope board is damaged. Run calibration to check for signal detection.
Autoscale does detect flat, dc signals so that is not a cause.
Error Message: Incorrect Calibration Factors
This message appears when you have upgraded your oscilloscope software, but not re-calibrated the Agilent Technologies 16533A or 16534A oscilloscope.
See the Logic Analysis System Installation Guide or Calibrating the Oscilloscope on page 10 for instructions on calibrating the oscilloscope.
Status Message: Waiting for IMB Arm
This message appears when the oscilloscope is being triggered by another instrument in the logic analysis system. The instrument that will trigger the oscilloscope has not yet found its own trigger, and therefore hasn't sent the IMB Arm signal to the oscilloscope.
If the other instrument has already triggered, perform the Self Test (see page 83) on the oscilloscope. If any of the tests fail, contact your Agilent Technologies Sales Office for service.
Performing the Self Tests. To verify that the oscilloscope hardware is operational, run the Self Test utility. The Self Tst function of the logic analysis system performs functional tests on both the system and any installed modules.
NOTE: The operational accuracy calibration requires that the oscilloscope hardware
meets specifications. The self test only requires that the hardware function. An oscilloscope can pass self-test and still fail calibration.
To Run the Self-Test Utility
1. If you have any work in progress, save it to a configuration file. (see the Agilent Technologies 16700A/B-Series Logic Analysis System help volume)
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2. From the system window, select the System Administration toolbar button.
3. Select the Admin tab, then select the Self Test... button. The system closes all windows before starting up Self Test.
4. Select Master Frame. If the module is in an expansion frame, select Expansion Frame.
5. Select the oscilloscope.
6. In the Self Test dialog box, select Te s t A l l . You can also run individual tests by selecting them. Tests that require you to do something must be run this way.
If any test fails, contact your local Agilent Technologies Sales Office or Service Center for assistance.
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Specifications and Characteristics

Specifications and Characteristics
NOTE: Specifications are valid after a 30 minute warm-up period, and within 10 °C
from the firmware calibration temperature.
NOTE: Definition of Terms
To understand the difference between specifications (see page 88) and characteristics (see page 88), and what gets a calibration procedure (see page 88) and what gets a function test (see page 89), refer to appropriate links within this note.
Specifications (see page 85)
Operating Environment (see page 85)
Characteristics (see page 86)
Specifications
Note: Specifications refer to the input to the BNC connector.
Bandwidth 16533A dc to 250 MHz 16534A dc to 500 MHz
dc offset accuracy +/- (1% of offset + 2% of full scale)
dc voltage measurement accuracy +/- (1.25% of full scale + offset accuracy + 0.016 div)
Time interval measurement accuracy +/- [(0.005% of delta T) + (2e-6 x delay setting) at maximum sampling rate, on a + 100 ps] single card, on a single acquisition
Trigger sensitivity from 10 mV/div to 10 V/div dc to 50 MHz 0.25 div 50 MHz to 500 MHz 0.5 div
Trigger sensitivity at 4 mV/div dc to 50 MHz 0.63 div 50 MHz to 500 MHz 1.25 div
Input resistance 1 Mohm +/- 1% 50 ohm +/- 1%
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Operating Environment
Characteristics
Power Requirements All power supplies required for operating the oscilloscope are supplied through the backplane connector in the logic analysis system.
Operating Environment Characteristics The oscilloscope module’s reliability is enhanced when operating the module within the following ranges:
- Indoor use only.
- Temperature: +20 degrees C to +35 degrees C
(+68 degrees F to +95 degrees F)
- Humidity: 20% to 80% noncondensing
General
Maximum sampling rate 16533A 1 GSa/S 16534A 2 GSa/S
Number of channels 2 to 8 channels using the same timebase and trigger.
Waveform record length 32768 points
Vertical (Voltage)
(characteristics refer to the input at the BNC connector)
Vertical sensitivity range 4 mV/div to 10 V/div in 1:2:4 steps
Vertical resolution 8 bits over 4 vertical divisions
Rise time (calculated from bandwidth) 16533A 1.4 ns 16534A 700 ps
dc gain accuracy +/- (1.25% of full scale + 0.08% per degree C difference from calibration temperature)
dc offset range (1:1 probe) Vertical sensitivity Offset range 4 mV/div - 100 mV/div +/- 2 V 100 mV/div - 400 mV/div +/- 10 V 400 mV/div - 2.5 V/div +/- 50 V
2.5 V/div - 10 V/div +/- 250 V
Probe attenuation Any ratio from 1:1 to 1000:1 factor
Channel-to-channel isolation (with channel sensitivities equal) dc to 50 MHz 40 dB 50 MHz to 250 MHz (16533A) 30 dB 50 MHz to 500 MHz (16534A) 30 dB
Maximum safe input voltage 1 Mohm +/- 250 Vdc + peak ac (&<10KHz), CAT I 50 ohm 5 Vrms, CAT I
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Input coupling 1 Mohm ac, dc 50 ohm dc only
Input C approximately 7 pF
Number of channels: 2,4,6, or 8 simultaneous channels using the same trigger OR up to 10 channels with independent triggers for each pair of channels. Maximum of 20 channels with Agilent Technologies 16701A expansion frame.
Horizontal (Time)
Timebase ranges 0.5 ns/div to 5 s/div
Timebase resolution 10 ps
Delay range, pre-trigger 81.8 s, 5 divisions
Delay range, post-trigger 2.5e3 seconds
Time interval measurement accuracy +/- [(0.005% of delta T) + (2e-6 x delay setting) for sampling rates other than + (0.15/sample rate)] maximum, for bandwidth-limited signals (signal rise time > 1.4/sample rate) on a single card, on a single acquisition
Time interval measurement accuracy +/- [(0.005% of delta T) + (2e-6 x delay setting) for 2, 3, or 4 cards operation on + 550 ps] a single timebase, for measurements made between channels on different cards, at maximum sampling rate
Tr ig ge r
Trigger level range Within display window (vertical offset +/- 2 divisions)
Immediate trigger mode Triggers immediately after arming condition is met
Edge trigger mode Triggers on rising or falling edge on channel 1 or channel 2
Pattern trigger mode Triggers on entering or exiting a specified pattern across both channels
Auto condition trigger mode Self-triggers if trigger is not satisfied within approximately 100 ms after arming
Events delay trigger mode The trigger can be set to occur on the nth occurrence of an edge or pattern, n <= 32000
Intermodule trigger mode Arms another measurement module or acti­ vates a trigger output on the rear panel BNC connector when the trigger condition is met
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Specifications and Characteristics
What is a Specification
A Specification is a numeric value, or range of values, that bounds the performance of a product parameter. The product warranty covers the performance of parameters described by specifications. Products shipped from the factory meet all specifications. Additionally, the products sent to Agilent Technologies Customer Service Centers for calibration and returned to the customer meet all specifications.
Specifications are verified by Calibration Procedures.
What is a Characteristic
Characteristics describe product performance that is useful in the application of the product, but that is not covered by the product warranty. Characteristics describe performance that is typical of the majority of a given product, but not subject to the same rigor associated with specifications.
Characteristics are verified by Function Tests.
What is a Calibration Procedure
Calibration procedures verify that products or systems operate within the specifications. Parameters covered by specifications have a corresponding calibration procedure. Calibration procedures include both performance tests and system verification procedure. Calibration procedures are traceable and must specify adequate calibration standards.
Calibration procedures verify products meet the specifications by comparing measured parameters against a pass-fail limit. The pass-fail limit is the specification less any required guardband.
The term "calibration" refers to the process of measuring parameters and referencing the measurement to a calibration standard rather than
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Specifications and Characteristics
the process of adjusting products for optimal performance, which is referred to as an "operational accuracy calibration".
What is a Function Test
Function tests are quick tests designed to verify basic operation of a product. Function tests include operators checks and operation verification procedures. An operators check is normally a fast test used to verify basic operation of a product. An operation verification procedure verifies some, but not all, specifications, and often at a lower confidence level than a calibration procedure.
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Run/Group Run Function

Run/Group Run Function
Using Run - Run All - Group Run
The Run/Stop functions are initiated by selecting icons in the icon bar at the top of the tool windows. All instrument, display, and analysis tool windows will have one of the Run icons shown below to initiate the run function.
When two or more instrument tools are configured, they can be run either independently or as a group. If run in a group, it is called an Intermodule measurement. Use the Intermodule Window (see the Agilent Technologies 16700A/B-Series Logic Analysis System help volume) to coordinate the arming in a "Group Run". A common "Group Run" configuration is to configure one instrument to trigger and then arm another instrument to start evaluation of its own trigger condition.
The Run Single icon appears if you have a single instrument configured in your measurement and you want to run a single acquisition.
The Run All icon always appears in the System, Workspace and Run Status windows. Also appears in instrument and display windows when you are using multiple instruments in your measurement and these instruments ARE NOT configured in an intermodule measurement (Group Run). This choice runs a single acquisition on all instruments in the configuration.
The Group Run icon appears in all windows when you are using multiple instruments, and these instruments are configured into a Group Run. This choice runs a single acquisition on all instruments in the Group Run configuration.
The Run Repetitive icon appears in all windows. It is used to run a Run Single, Run All, and a Group Run acquisition repetitively. The current run mode will continue to run until Cancel is selected.
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Run/Group Run Function
Using Stop
The Stop icon terminates all of the run functions shown above.
Stops a single instrument running a measurement (perhaps waiting for a trigger condition).
Stops all instruments running separate measurements (easily viewed from the Workspace window).
Stops all instruments running in a Group Run configuration.
See Also
Demand Driven Data” on page 92
Checking Run Status on page 91
Checking Run Status
The Run Status dialog provides status information about the currently configured instruments, and the status of the run with respect to the trigger specification.
To access the Run Status dialog, select the Run Status icon in the System Window, or, select Window -> System -> Run Status
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Demand Driven Data
When an analyzer measurement occurs, acquisition memory is filled with data that is then transferred to the display memory of the analysis or display tools you are using, as needed by those tools. In normal use, this demand driven data approach saves time by not transferring unnecessary data.
Since acquisition memory is cleared at the beginning of a measurement, stopping a run may create a discrepancy between acquisition memory and the memory buffer of connected tools. Without a complete trace of acquisition memory, the display memory will appear to have ’holes’ in it which appear as filtered data.
This situation will occur in these cases:
If you stop a repetitive measurement after analyzer data has been cleared and before the measurement is complete.
If a trigger is not found by the analyzer and the run must be stopped to regain control.
To make sure all of the data in a repetitive run is available for viewing:
In the workspace, attach a Filter tool to the output of the analyzer.
In the Filter, select "Pass Matching Data"
In the filter terms, assure the default pattern of all "Don't Cares" (Xs).
This configuration will always transfer all data from acquisition memory. While this configuration will increase the time of each run, it will guarantee that repetitive run data is available regardless of when it is stopped.
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Glossary

absolute Denotes the time period or count of states between a captured state and the trigger state. An absolute count of -10 indicates the state was captured ten states before the trigger state was captured.
acquisition Denotes one complete cycle of data gathering by a measurement module. For example, if you are using an analyzer with 128K memory depth, one complete acquisition will capture and store 128K states in acquisition memory.
analysis probe A probe connected to a microprocessor or standard bus in the device under test. An analysis probe provides an interface between the signals of the microprocessor or standard bus and the inputs of the logic analyzer. Also called a preprocessor.
analyzer 1 In a logic analyzer with two machines, refers to the machine that is on by default. The default name is Analyzer<N>, where N is the slot letter.
analyzer 2 In a logic analyzer with two machines, refers to the machine that is off by default. The default name is Analyzer<N2>, where N is the slot letter.
armed before it can search for its trigger condition. Typically, instruments are armed immediately when Run or Group Run is selected. You can set up one instrument to arm another using the Intermodule Window. In these setups, the second instrument cannot search for its trigger condition until it receives the arming signal from the first instrument. In some analyzer instruments, you can set up one analyzer machine to arm the other analyzer machine in the Trigger Window.
asterisk (*) See edge terms, glitch, and labels.
bits Bits represent the physical logic analyzer channels. A bit is a channel that has or can be assigned to a label. A bit is also a position in a label.
card This refers to a single instrument intended for use in the Agilent Technologies 16600A-series or 16700A/B-series mainframes. One card fills one slot in the mainframe. A module may comprise a single card or multiple cards cabled together.
channel The entire signal path from the probe tip, through the cable and module, up to the label grouping.
arming An instrument tool must be
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click When using a mouse as the
Glossary
pointing device, to click an item, position the cursor over the item. Then quickly press and release the left mouse button.
clock channel A logic analyzer channel that can be used to carry the clock signal. When it is not needed for clock signals, it can be used as a data channel, except in the Agilent Technologies 16517A.
context record A context record is a small segment of analyzer memory that stores an event of interest along with the states that immediately preceded it and the states that immediately followed it.
context store If your analyzer can perform context store measurements, you will see a button labeled Context Store under the Trigger tab. Typical context store measurements are used to capture writes to a variable or calls to a subroutine, along with the activity preceding and following the events. A context store measurement divides analyzer memory into a series of context records. If you have a 64K analyzer memory and select a 16­state context, the analyzer memory is divided into 4K 16-state context records. If you have a 64K analyzer memory and select a 64-state context, the analyzer memory will be
divided into 1K 64-state records.
count The count function records periods of time or numbers of state transactions between states stored in memory. You can set up the analyzer count function to count occurrences of a selected event during the trace, such as counting how many times a variable is read between each of the writes to the variable. The analyzer can also be set up to count elapsed time, such as counting the time spent executing within a particular function during a run of your target program.
cross triggering Using intermodule capabilities to have measurement modules trigger each other. For example, you can have an external instrument arm a logic analyzer, which subsequently triggers an oscilloscope when it finds the trigger state.
data channel A channel that carries data. Data channels cannot be used to clock logic analyzers.
data field A data field in the pattern generator is the data value associated with a single label within a particular data vector.
data set A data set is made up of all labels and data stored in memory of any single analyzer machine or
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Glossary
instrument tool. Multiple data sets can be displayed together when sourced into a single display tool. The Filter tool is used to pass on partial data sets to analysis or display tools.
debug mode See monitor.
delay The delay function sets the
horizontal position of the waveform on the screen for the oscilloscope and timing analyzer. Delay time is measured from the trigger point in seconds or states.
demo mode An emulation control session which is not connected to a real target system. All windows can be viewed, but the data displayed is simulated. To start demo mode, select Start User Session from the Emulation Control Interface and enter the demo name in the Processor Probe LAN Name field. Select the Help button in the Start User Session window for details.
device under test The system under test, which contains the circuitry you are probing. Also known as a target system.
don’t care For terms, a "dont care" means that the state of the signal (high or low) is not relevant to the measurement. The analyzer ignores the state of this signal when determining whether a match occurs on an input label. "Dont care" signals are still sampled and their values can be displayed with the rest of the data. Dont cares are represented by the X character in numeric values and the dot (.) in timing edge specifications.
dot (.) See edge terms, glitch, labels, and don’t care.
double-click When using a mouse as the pointing device, to double-click an item, position the cursor over the item, and then quickly press and release the left mouse button twice.
deskewing To cancel or nullify the effects of differences between two different internal delay paths for a signal. Deskewing is normally done by routing a single test signal to the inputs of two different modules, then adjusting the Intermodule Skew so that both modules recognize the signal at the same time.
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drag and drop Using a Mouse: Position the cursor over the item, and then press and hold the left mouse button. While holding the left mouse button down, move the mouse to drag the item to a new location. When the item is positioned where you want it, release the mouse button.
Glossary
Using the Touchscreen: Position your finger over the item, then press and hold finger to the screen. While holding the finger down, slide the finger along the screen dragging the item to a new location. When the item is positioned where you want it, release your finger.
edge mode In an oscilloscope, this is the trigger mode that causes a trigger based on a single channel edge, either rising or falling.
edge terms Logic analyzer trigger resources that allow detection of transitions on a signal. An edge term can be set to detect a rising edge, falling edge, or either edge. Some logic analyzers can also detect no edge or a glitch on an input signal. Edges are specified by selecting arrows. The dot (.) ignores the bit. The asterisk (*) specifies a glitch on the bit.
emulation module A module within the logic analysis system mainframe that provides an emulation connection to the debug port of a microprocessor. An E5901A emulation module is used with a target interface module (TIM) or an analysis probe. An E5901B emulation module is used with an E5900A emulation probe.
emulation probe The stand-alone equivalent of an emulation module. Most of the tasks which can be performed using an emulation module can also be performed using an emulation probe connected to your logic analysis system via a LAN.
emulator An emulation module or an emulation probe.
Ethernet address See link-level address.
events Events are the things you are looking for in your target system. In the logic analyzer interface, they take a single line. Examples of events are Label1 = XX and Timer 1 > 400 ns.
filter expression The filter expression is the logical OR combination of all of the filter terms. States in your data that match the filter expression can be filtered out or passed through the Pattern Filter.
filter term A variable that you define in order to specify which states to filter out or pass through. Filter terms are logically ORed together to create the filter expression.
Format The selections under the logic analyzer Format tab tell the
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Glossary
logic analyzer what data you want to collect, such as which channels represent buses (labels) and what logic threshold your signals use.
frame The Agilent Technologies 16600A-series or 16700A/B-series logic analysis system mainframe. See also logic analysis system.
gateway address An IP address entered in integer dot notation. The default gateway address is 0.0.0.0, which allows all connections on the local network or subnet. If connections are to be made across networks or subnets, this address must be set to the address of the gateway machine.
glitch A glitch occurs when two or more transitions cross the logic threshold between consecutive timing analyzer samples. You can specify glitch detection by choosing the asterisk (*) for edge terms under the timing analyzer Trigger tab.
grouped event A grouped event is a list of events that you have grouped, and optionally named. It can be reused in other trigger sequence levels. Only available in Agilent Technologies 16715A, 16716A, and 16717A logic analyzers.
held value A value that is held until
the next sample. A held value can exist in multiple data sets.
immediate mode In an oscilloscope, the trigger mode that does not require a specific trigger condition such as an edge or a pattern. Use immediate mode when the oscilloscope is armed by another instrument.
interconnect cable Short name for module/probe interconnect cable.
intermodule bus The intermodule bus (IMB) is a bus in the frame that allows the measurement modules to communicate with each other. Using the IMB, you can set up one instrument to arm another. Data acquired by instruments using the IMB is time-correlated.
intermodule Intermodule is a term used when multiple instrument tools are connected together for the purpose of one instrument arming another. In such a configuration, an arming tree is developed and the group run function is designated to start all instrument tools. Multiple instrument configurations are done in the Intermodule window.
internet address Also called Internet Protocol address or IP address. A 32-bit network address. It
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Glossary
is usually represented as decimal numbers separated by periods; for example, 192.35.12.6. Ask your LAN administrator if you need an internet address.
labels Labels are used to group and identify logic analyzer channels. A label consists of a name and an associated bit or group of bits. Labels are created in the Format tab.
line numbers A line number (Line #s) is a special use of symbols. Line numbers represent lines in your source file, typically lines that have no unique symbols defined to represent them.
link-level address Also referred to as the Ethernet address, this is the unique address of the LAN interface. This value is set at the factory and cannot be changed. The link-level address of a particular piece of equipment is often printed on a label above the LAN connector. An example of a link-level address in hexadecimal: 0800090012AB.
16700A/B-series mainframes, and all tools designed to work with it. Usually used to mean the specific system and tools you are working with right now.
machine Some logic analyzers allow you to set up two measurements at the same time. Each measurement is handled by a different machine. This is represented in the Workspace window by two icons, differentiated by a 1 and a 2 in the upper right-hand corner of the icon. Logic analyzer resources such as pods and trigger terms cannot be shared by the machines.
markers Markers are the green and yellow lines in the display that are labeled x, o, G1, and G2. Use them to measure time intervals or sample intervals. Markers are assigned to patterns in order to find patterns or track sequences of states in the data. The x and o markers are local to the immediate display, while G1 and G2 are global between time correlated displays.
local session A local session is when you run the logic analysis system using the local display connected to the product hardware.
logic analysis system The Agilent Technologies 16600A-series or
98
master card In a module, the master card controls the data acquisition or output. The logic analysis system references the module by the slot in which the master card is plugged. For example, a 5-card Agilent Technologies 16555D
Glossary
would be referred to as Slot C: machine because the master card is
in slot C of the mainframe. The other cards of the module are called expansion cards.
menu bar The menu bar is located at the top of all windows. Use it to select File operations, tool or system
Options, and tool or system level Help.
message bar The message bar displays mouse button functions for the window area or field directly beneath the mouse cursor. Use the mouse and message bar together to prompt yourself to functions and shortcuts.
module/probe interconnect cable
The module/probe interconnect cable connects an E5901B emulation module to an E5900B emulation probe. It provides power and a serial connection. A LAN connection is also required to use the emulation probe.
module An instrument that uses a single timebase in its operation. Modules can have from one to five cards functioning as a single instrument. When a module has more than one card, system window will show the instrument icon in the slot of the master card.
monitor When using the Emulation Control Interface, running the monitor means the processor is in debug mode (that is, executing the debug exception) instead of executing the user program.
panning The action of moving the waveform along the timebase by varying the delay value in the Delay field. This action allows you to control the portion of acquisition memory that will be displayed on the screen.
pattern mode In an oscilloscope, the trigger mode that allows you to set the oscilloscope to trigger on a specified combination of input signal levels.
pattern terms Logic analyzer resources that represent single states to be found on labeled sets of bits; for example, an address on the address bus or a status on the status lines.
period (.) See edge terms, glitch, labels, and don’t care.
pod pair A group of two pods containing 16 channels each, used to physically connect data and clock signals from the unit under test to the analyzer. Pods are assigned by pairs in the analyzer interface. The number of pod pairs avalaible is determined
99
Glossary
by the channel width of the instrument.
pod See pod pair
point To point to an item, move the
mouse cursor over the item, or position your finger over the item.
preprocessor See analysis probe.
primary branch The primary
branch is indicated in the Trigger sequence step dialog box as either
the Then find or Trigger on selection. The destination of the primary branch is always the next state in the sequence, except for the Agilent Technologies 16517A. The primary branch has an optional occurrence count field that can be used to count a number of occurrences of the branch condition. See also secondary branch.
probe A device to connect the various instruments of the logic analysis system to the target system. There are many types of probes and the one you should use depends on the instrument and your data requirements. As a verb, "to probe" means to attach a probe to the target system.
processor probe See emulation probe.
range terms Logic analyzer resources that represent ranges of values to be found on labeled sets of bits. For example, range terms could identify a range of addresses to be found on the address bus or a range of data values to be found on the data bus. In the trigger sequence, range terms are considered to be true when any value within the range occurs.
relative Denotes time period or count of states between the current state and the previous state.
remote display A remote display is a display other than the one connected to the product hardware. Remote displays must be identified to the network through an address location.
remote session A remote session is when you run the logic analyzer using a display that is located away from the product hardware.
right-click When using a mouse for a pointing device, to right-click an item, position the cursor over the item, and then quickly press and release the right mouse button.
sample A data sample is a portion of a data set, sometimes just one point. When an instrument samples the target system, it is taking a single
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