Teledyne Lecroy AP033 User manual

Operator’s
Manual
AP033 Active
Differential Probe
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AP033 Active Differential Probe
Operator’s Manual
February 2017
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© 2017 Teledyne LeCroy, Inc. All rights reserved.
Unauthorized duplication of Teledyne LeCroy documentation materials other than for
internal sales and distribution purposes is strictly prohibited. Clients are permitted to
duplicate and distribute Teledyne LeCroy documentation for their own internal training
purposes.
Teledyne LeCroy is a registered trademark of Teledyne LeCroy, Inc. Windows is a
registered trademark of Microsoft Corporation. Other product or brand names are
trademarks or requested trademarks of their respective holders. Information in this
publication supersedes all earlier versions. Specifications are subject to change without
notice.
928154-00 Rev A
February 2017
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Operator’s Manual
i
Contents
Safety Instructions.........................................................................................................1
Overview .......................................................................................................................3
Description...................................................................................................................3
Applications .................................................................................................................3
Standard Accessories...................................................................................................3
Optional Accessories....................................................................................................4
Oscilloscope Software Compatibility ...........................................................................4
Specifications ................................................................................................................5
Operation......................................................................................................................8
Connecting the Probe to the Test Instrument.............................................................8
Connecting the Probe to the Test Circuit ....................................................................8
Probe Input Loading...................................................................................................10
Grounding the Probe .................................................................................................10
Selecting the Proper Range........................................................................................11
Operating with Teledyne LeCroy Oscilloscopes.........................................................13
Designing Test Fixtures for the AP033 Probe ............................................................16
Maintenance ...............................................................................................................17
Cleaning .....................................................................................................................17
Calibration Interval ....................................................................................................17
Service Strategy .........................................................................................................17
Troubleshooting ..........................................................................................................18
Returning a Probe .......................................................................................................20
Matching Procedure for ÷10 Plugs...............................................................................21
Equipment Required..................................................................................................21
Procedure ..................................................................................................................22
Performance Verification ............................................................................................24
Test Equipment Required ..........................................................................................24
Preliminary Procedure ...............................................................................................25
Test Procedure...........................................................................................................26
AP033 Performance Verification Test Record ...........................................................32
Adjustment Procedure ................................................................................................34
Introduction...............................................................................................................34
Test Equipment Required ..........................................................................................35
Preliminary Procedure ...............................................................................................37
Procedure ..................................................................................................................38
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AP033 Active Differential Probe
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Reference Information ................................................................................................46
Differential Mode and Common Mode......................................................................46
Differential Mode Range and Common Mode Range................................................46
Common Mode Rejection Ratio.................................................................................47
Certifications..............................................................................................................48
Warranty....................................................................................................................50
Technical Support ......................................................................................................51
Notes ..........................................................................................................................52
Figures
Figure 1, Typical CMRR Graphs ...........................................................................................7
Figure 2, channel setup dialog with AP033 probe dialog behind it. ...................................8
Figure 3, AP033 Equivalent Input Model ..........................................................................10
Figure 4, AP033 Block Diagram .........................................................................................11
Figure 5, AP033 probe dialog with probe controls and attributes....................................13
Figure 6, Effect of Differential Offset ................................................................................15
Figure 7, Layout dimensions for test fixtures....................................................................16
Figure 8, ÷10 Attenuator Adjustment Locations...............................................................23
Figure 9, AP033 Logic Board..............................................................................................38
Figure 10, Probe Tip Adjustment Locations ......................................................................39
Figure 11, Amplifier Board Adjustment Locations ............................................................39
Figure 12, ÷10 Effective Gain Indicator.............................................................................40
Figure 13, Common Mode and Differential Mode Range .................................................47
Tables
Table 1, Dynamic ranges and input capacitance at different attenuator settings............12
Table 2, Recommended settings to obtain desired equivalent Volts/Division .................14
Table 3, Performance Verification Test Equipment ..........................................................24
Table 4, Adjustment Test Equipment................................................................................35
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Operator’s Manual
1
Safety Instructions
This section contains instructions that must be observed to keep this oscilloscope
accessory operating in a correct and safe condition. You are required to follow generally
accepted safety procedures in addition to the precautions specified in this section. The
overall safety of any system incorporating this accessory is the responsibility of the
assembler of the system.
Symbols
These symbols may appear on the probe body or in this manual to alert you to important
safety considerations.
HIGH VOLTAGE, risk of electric shock.
CAUTION of Potential damage to probe or instrument it is connected to, or
WARNING of potential bodily injury. Attend to the accompanying information to
protect against personal injury or damage. Do not proceed unt
il conditions are fully
understood and met.
ELECTROSTATIC DISCHARGE (ESD) HAZARD. The probe is susceptible to damage if
anti-static measures are not taken.
DOUBLE INSULATION
PROTECTIVE (EARTH) TERMINAL
Precautions
To avoid personal injury, or damage to the probe or test instrument, comply with the
following safety precautions.
Use product only as specified.
Connect and disconnect properly. Connect probe to the measurement instrument before
connecting the test leads to a circuit/signal being tested.
Use only accessories compatible with the probe. Use only accessories that are rated for
the application. Ensure connections between probe input leads and probe accessories are
secure before connecting them to a voltage source.
Do not overload. To avoid electric shock, do not apply any potential that exceeds the
maximum rating of the probe and/or the probe accessory, whichever is less. Observe all
terminal ratings of the instrument before connecting the probe.
Be careful not to damage the insulation surface when making measurements.
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AP033 Active Differential Probe
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Use only within operational environment listed. Do not use in wet or explosive
atmospheres. Keep product surfaces clean and dry. Use indoors only.
Handle with care. Probe accessory tips are sharp. They can puncture skin or cause other
bodily injury if not handled properly.
Keep fingers behind the finger guard of the probe accessories.
Do not operate with suspected failures. Before each use, inspect the probe and
accessories for any damage such as tears or other defects in the probe body, cable jacket,
accessories, etc. If any part is damaged, cease operation immediately and sequester the
probe from inadvertent use.
Operating Environment
Only use the product within this operating environment:
Temperature: 0° to 50° C
Humidity: Maximum relative humidity 90 % for temperatures up to 31° C decreasing
linearly to 50% relative humidity at 50° C
Altitude: Up to 10,000 ft (3,048 m)
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Operator’s Manual
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Overview
Description
The AP033 is a wide band differential active probe. The probe features low noise, low input
capacitance, high common mode rejection, and FET-buffered inputs in the probe head. User
selectable attenuation and offset give the probe flexibility to measure a large range of signal
amplitudes. Plug-on attenuator and AC coupling accessories further extend the application
range. Interconnect accessories included allow connection to surface mount and through-
hole components with minimal signal degradation. The input receptacles in the probe head
are compatible with standard 0.025 in. (0.635 mm) square pins, providing a convenient low-
cost method of creating device characterization test fixtures.
The probe is powered directly from a Teledyne LeCroy oscilloscope through the ProBus®
interface. The ProBus interface also allows local control of the probe through the
oscilloscope user interface and remote control through the interface buses, (GPIB, RS-
232). The optional ADPPS power supply allows the AP033 to be used with other
instruments such as spectrum analyzers, network analyzers, and oscilloscopes without
ProBus interface.
Applications
The AP033 is ideal for acquiring high speed differential signals such as those found in disk
drive read channels, differential LAN, video, etc. It can also be used with spectrum
analyzers to acquire signals in some RF systems (for example, balanced IF mixers in hand
held cellular telephones). The high impedance characteristics of both inputs allow the
probe to be used as a FET probe to make single-ended measurements in digital systems
without introducing a ground loop, as a conventional FET probe would.
Standard Accessories
Hard Case
÷10 Plug-on Attenuator
Plug-on AC Coupler
Probe Connection Accessory Kit:
Flex Lead Set (1)
Mini Clip, 0.8 mm (3)
Mini Clip, 0.5 mm (2)
Ground Lead (1)
Offset Pins, Round (4)
Square Pin Header Strip (1)
Manual, AP033 Active Differential Probe Operator’s Manual
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AP033 Active Differential Probe
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Optional Accessories
Teledyne LeCroy
Part Number
Description
PK033
Accessory Kit, AP033 without AC Coupler and Attenuator
AP03X-FLEX-LEAD
Flex Lead
405400003
Offset Pin, package of 10
AP033-ATTN
Plug-On Attenuator, /10, AP033
AP03X-AC-COUPLER
Plug-On AC Coupler
ADPPS
Power Supply Adapter for Non-ProBus Oscilloscopes
Oscilloscope Software Compatibility
Teledyne LeCroy LC series oscilloscopes must have legacy software version 8.1.0 or higher
loaded. All X-Stream oscilloscopes are compatible.
To verify the software version installed on the oscilloscope, either:
• Press the SHOW STATUS button on the front panel (where available), then select
System.
• Choose Help > About or Support > About from the oscilloscope menu bar.
NOTE: When the probe is used with earlier versions of legacy software, Offset can only be
controlled through the buttons on the probe body. Also, the scale factor will be displayed
incorrectly in some modes.
To upgrade the software in your oscilloscope, go to:
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Operator’s Manual
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Specifications
Nominal Characteristics
Nominal characteristics describe parameters and attributes that have are guaranteed by
design, but do not have associated tolerances.
Input Configuration: True Differential (+ / – inputs); with shield Ground connector
Effective Gain:1X1, X10, ÷10, ÷100 2
Input coupling:DC (AC Coupling obtained by installing AC Coupling Adapter)
Differential Mode Range:
(10X Gain): ±40 mV (÷1 Attenuation)
±400 mV(÷10 Attenuation)
±4 V (÷100 Attenuation)
(1X Gain): ±400 mV(÷1 Attenuation)
±4 V (÷10 Attenuation)
±40 V (÷100 Attenuation)
Common Mode Range:±4.2 V (÷1 Attenuation)
±42 V (÷10 Attenuation)
±42 V (÷100 Attenuation)
Maximum Input Voltage:±42 V either input from ground
Warranted Electrical Characteristics
Warranted characteristics are parameters with guaranteed performance. Unless
otherwise noted, tests are provided in the Performance Verification Procedure for all
warranted specifications.
LF Gain Accuracy:2% into 50 Ω load 3, measured at 1 kHz with 0 V offset
Common Mode Rejection Ratio:4
(Probe head grounded, DC Coupled, ÷1 attenuation without external attenuator):
70 Hz ≥3160:1(70 dB)
1 MHz ≥1000:1(60 dB)
250 MHz ≥5:1(14 dB)
1. From combination of gain, internal and external attenuation.
2. Use external plug-on ÷10 attenuator for ÷100.
3. Output impedance 50 Ω, intended to drive 50 Ω. Add uncertainty of termination impedance to accuracy.
4. Teledyne LeCroy measures CMRR with a fixture that connects the probe tip ground to the signal source
ground. This method is necessary to obtain a reproducible CMRR measurement. Not grounding the probe
tip can actually improve CMRR by allowing some of the common mode signal to be impressed across the
entire length of the probe cable instead of from probe tip to probe ground, however, this CMRR
improvement depends on proximity to probe cable ground, and is therefore non-reproducible.
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AP033 Active Differential Probe
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Typical Electrical Characteristics
Typical characteristics are parameters with no guaranteed performance. Tests for typical
characteristics are not provided in the Performance Verification Procedure.
Bandwidth, probe only: (-3 dB): DC to 500 MHz
Risetime, probe only:≤700 ps (÷10 Attenuation)
≤875 ps (÷1 Attenuation)
Residual Offset:
(Ref. to input) ≤ 100 μV (÷1 Attenuation)
≤ 1.5 mV (÷10 Attenuation)
Differential Offset Range:±400 mV (÷1 Attenuation)
± 4 V (÷10 Attenuation)
± 40 V (÷100 Attenuation)
CMRR:See Figure 1 below
Input Resistance: 1 M Ω
(each side to ground)
Input Capacitance:≤1.6 pF (÷10 Attenuation)
(between inputs) ≤3.1 pF (÷1 Attenuation)
Input Capacitance: ≤ 3 pF (÷10 Attenuation)
(each side to ground) ≤ 6 pF (÷1 Attenuation)
Noise:6 nV/√Hz (÷1 Attenuation, 10X Gain)
(referred to input, 10 nV/√Hz (÷1 Attenuation, 1X Gain)
5 to 1000 MHz) 60 nV/√Hz (÷10 Attenuation, 10X Gain)
115 nV/√Hz (÷10 Attenuation, 1X Gain)
Output Impedance:50 Ωnominal, intended to drive 50 Ω
Harmonic Distortion:
(3rdorderdistortion): -52 dB below fundamental (200 mVp-p output at 100 MHz)
(3rd order intercept): +15 dBm (at 100 MHz measured at output)
AC Coupling LF Cutoff: 1.6 Hz (-3dB)
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Operator’s Manual
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Figure 1, Typical CMRR Graphs
General Characteristics
Temperature:0° to 50° C Operating
-40° to 75° C Storage
Input Connectors:Compatible with 0.025” (0.635 mm) square pins
0.036” (0.91 mm) maximum diameter (for round pins)
Power Requirements:Powered from oscilloscope through ProBus interface or with
ADPPS power supply.
Dimensions
Control Housing:Length:3.625 in (9.2 cm)
Width: 1.50 in (3.8 cm)
Height: 1.00 in (2.5 cm)
Head:Length: 4.0 in (10.2 cm) w/o Attenuator or AC Coupler
Width: 0.89 in (2.25 cm)
Height: 0.625 in (1.6 cm)
Cable:Length: 42 in (106.7 cm)
Diameter: 0.275 in (7.0 mm)
Weight:Probe only: 6.4 oz (0.18 kg)
Shipping: 2 lbs, 8.4 oz (1.15 kg)
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AP033 Active Differential Probe
8
Operation
CAUTION: The input circuits in the AP033 incorporate components that protect
the probe from damage resulting from electrostatic discharge (ESD). Keep in
mind that this is an active probe, and it should be handled carefully to avoid
damage. When using the AP033, you are advised to take precautions against
potential instrument damage due to ESD.
Connecting the Probe to the Test Instrument
Attach the probe output connector to the oscilloscope input connector. When used with
a Teledyne LeCroy oscilloscope equipped with ProBus inputs, the oscilloscope will
recognize the probe, set the input termination to 50 Ω, and activate the probe control
functions on the oscilloscope user interface. These appear on the AP033 dialog behind
the input channel setup dialog.
Figure 2, channel setup dialog with AP033 probe dialog behind it.
To use the AP033 Active Differential Probe with instrumentation not equipped with a
ProBus interface, it is necessary to use the ADPPS Power Supply. Attach the ADPPS
connector to the probe output connector. The output connector of the ADPPS is a
standard male BNC that can be directly connected to another instrument. If necessary,
the output of the ADPPS can be interconnected with a 50 Ωcoaxial cable. To minimize the
effect of skin loss, this cable should be 1 m or less in length. The AP033 is designed to
drive a 50 Ωload. The gain will be uncalibrated if the output is not correctly terminated. If
you are using the probe with an instrument with a high input impedance, place a 50
instrument input before attaching the ADPPS..
Connecting the Probe to the Test Circuit
At the probe tip, two inputs and a ground connection are available for connecting the
probe to a circuit under test. For accurate measurements, both the + and – inputs must
always be connected to the test circuit. The ground connection is optional. Positive
voltages applied to the + input relative to the – input will deflect the oscilloscope trace
toward the top of the screen.
Positive voltages applied to the + input relative to the – input will deflect the oscilloscope
trace toward the top of the screen.
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To maintain the high performance capability of the probe, user care in connecting the
probe to the test circuit. Increasing the parasitic capacitance or inductance in the input
paths may introduce a “ring,” or slow the rise time of fast signals. To minimize these
effects, use the shortest length possible when connecting the probe to the circuit under
test. Input leads that form a large loop area (even shielded coaxial cables) will pick up any
radiated magnetic field that passes through the loop, and may induce noise in the probe
inputs. Because this signal will appear as a differential mode signal, the probe’s common
mode rejection will not remove it. You can greatly reduce this effect by using short
interconnection leads, and twisting them together to minimize the loop area.
High common mode rejection requires precise matching of the relative gain or
attenuation in the + and – input signal paths. Mismatches in additional parasitic
capacitance, inductance, delay, and a source impedance difference between the + and –
signal paths will lower the common mode rejection ratio. Therefore, it is desirable to use
the same length and type of wire and connectors for both input connections. When
possible, try to connect the inputs to points in the circuit with approximately the same
source impedance.
If AC coupling is desired, install the AC coupling accessory on the probe tip before
connecting it to the test circuit. The low-frequency cutoff (–3 dB point) of the AC coupler
is approximately 1.6 Hz.
If the voltage in the test circuit requires more than ÷10 attentuation, add the external ÷10
attenuator to the probe tip. If using both the external attenuator and AC coupler, install
the attenuator on the probe tip first, then install the AC coupler on the attenuator input.
In addition to being compatible with the included lead set, the probe input connectors
will mate with standard 0.025 in. (0.635 mm) square pins in any rotational orientation. To
avoid damaging the input connectors, do not attempt to insert connectors or wire larger
than 0.036 in. (0.91 mm) in diameter. Avoid rotating square pins after they are inserted
into the input connectors.
The included accessories simplify the task of connecting the probe to the test circuit:
• Use the small (0.5 mm) mini clips with the flexible lead set when connecting to
fine-pitch surface mount IC leads.
• Use the larger (0.8 mm) mini clips to connect to through-hole leaded
components.
• Use the offset round pins for hand-held probing applications. Reposition the pins
by rotating them to obtain the required spacing.
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AP033 Active Differential Probe
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Probe Input Loading
Attaching any probe to a test circuit will add some loading. In most applications, the high
impedance of the AP033 Active Differential Probe inputs imparts an insignificant load to
the test circuit. However at very high frequencies, the capacitive reactance of the probe’s
input capacitance may load the circuit enough to affect measurement accuracy. The
equivalent model of the probe input circuits is shown below:
Figure 3, AP033 Equivalent Input Model
Grounding the Probe
The single lead along with one of the larger (0.8 mm) mini clips can be used to ground the
probe to the test circuit. Insert the pin end of the lead into the receptacle marked:
CAUTION: Do not use the attenuator encoding receptacle (unmarked socket
near the
– input) to ground the probe. Connection to the encoding receptacle
will not
provide adequate grounding and may result in an incorrect effective gain
indication.
In many cases it is not necessary to ground the probe to the circuit under test. However,
if the test circuit is isolated from earth ground, it is usually necessary to connect the
probe ground to a point in the circuit. Grounding test circuits that are referenced to earth
ground may improve the fidelity of high frequency components in the waveforms. The
potential for improvement with grounding will vary depending on the common mode
source impedance. However, connecting the probe ground to a circuit that is referenced
to earth ground can create a ground loop that may add noise to low amplitude signals.
The rejection of high frequency common mode signals is improved when the probe head
is ungrounded.
The best recommendation for connecting or not connecting the probe ground is to try
both configurations and select the one that performs the best.
M
M
M
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Operator’s Manual
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NOTE: The AP033 Active Differential Probe transmits the measured signal differentially
through the probe cable. This essentially eliminates signal degradation from ground loop
effects within the probe. However, creating a ground loop may introduce signal
distortions in the test circuit itself, or in any coaxial cable between the ADPPS power
supply and the test instrument.
Selecting the Proper Range
The AP033 has two independent controls that set the common mode range and
equivalent volts/division. The probe gain can be set to x1 or x10. The gain control (GAIN)
only affects the differential mode range of the probe. A separate input attenuation
control (ATTEN) sets the probe input attenuator to either ÷1or ÷10. See Figure 4.
Figure 4, AP033 Block Diagram
The attenuator is located at the probe input and, therefore, affects both the differential
mode and common mode ranges. (Refer to the Reference Section for definitions of
Common Mode and Differential Mode.) By using the plug-on attenuator, you can extend
the attenuation range to ÷100. The maximum ranges are given in Table 1.
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AP033 Active Differential Probe
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Table 1, Dynamic ranges and input capacitance at different attenuator settings
÷1 Attenuation ÷10 Attenuation ÷100 Attenuation
Common Mode Range ± 4.2 V ± 42 V ± 42 V
Differential Mode Range with x1 Gain* ± 400 mV ± 4 V ± 40 V
Differential Mode Range with x10 Gain* ± 40 mV ± 400 mV ± 4 V
Input Capacitance, each side to Ground 6.0 pF 3.0 pF 1.9 pF
Input Capacitance each side to Ground
with AC Coupler 7.3 pF 4.3 pF 3.2 pF
*Offset moves the center point of this range.
When you are using a differential probe or amplifier, be careful not to exceed the
common mode range. Because the common mode signal is rejected by the probe, and
not displayed, changes in the amplitude of the common mode component are not
apparent. Exceeding the common mode range may introduce distortion into the AP033
output. To reduce the possibility of errors caused by exceeding the common mode range,
the probe monitors the input voltage. If the common mode range is exceeded when the
÷1input attenuator is selected, the probe will automatically switch to the
÷10 attenuator. If the voltage on either input exceeds 55 volts, both the ÷1and
÷10 attenuator lights will alternately flash to alert the user to the over-range condition.
There are two combinations which result in x1 effective gain. A ÷10 attenuation with x10
gain results in higher common mode range and lower input capacitance, but it increases
the noise referred to the input. Conversely, ÷1attenuation with x1 gain reduces the
noise at the expense of less common mode range and greater input capacitance.
Circuitry in the probe decodes the effective gain of the probe based on the settings of the
gain, internal attenuation and the presence of the external attenuator. The resulting
effective gain is displayed on the probe front panel.
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Operator’s Manual
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Operating with Teledyne LeCroy Oscilloscopes
When the AP033 probe is connected to an oscilloscope equipped with the ProBus
interface, the displayed scale factor and measurement values will be adjusted to account
for the effective gain of the probe. The probe gain, internal attenuation, and offset can be
conveniently controlled through the oscilloscope’s user interface.
In X-Stream software versions, the AP033 dialog appears behind the Channel dialog. The
probe coupling, gain control type (Auto or Manual), attenuation, and gain are all set here:
Figure 5, AP033 probe dialog with probe controls and attributes.
NOTE: In legacy software versions 7.4 and later, probe controls can be found on the
oscilloscope COUPLING menu. On legacy versions before 7.4, all these settings are
controlled through the physical buttons on the probe body.
There are two modes of gain control: Auto and Manual.
Auto Gain Control
The oscilloscope defaults to Auto mode when the probe is first attached. In Auto mode,
the oscilloscope VOLTS/DIV knob controls the oscilloscope’s scale factor, while the
OFFSET knob controls probe offset. AP033 gain and attenuation are set automatically to
give the full available dynamic range: 200 μV/div to 1 V/div (without external attenuator),
or 2 mV/div to 10 V/div (with external ÷10 attenuator installed). Some of the transitions
in scale factor will result in a change of the attenuation in the AP033 probe. The common
mode range, input capacitance, and noise level of the probe will change with the probe
attenuator setting. For Volts/Div settings which can be produced with more than one
combination of probe gain and attenuation settings, Auto mode selects the combination
which results in greater common mode range and lower input capacitance.
NOTE: In this mode, you cannot control the probe using any of the buttons on the probe
body, only the oscilloscope touch screen and front panel.
Manual Gain Control
In some situations, you may wish to select probe settings optimized for the lowest noise
performance with lower common mode range. Likewise, you may require that the probe
not change input capacitance, noise, or common mode range as you change the
VOLTS/DIV setting. These requirements can be met by setting the probe to Manual gain
control mode. When set to Manual mode, the dynamic range of the VOLTS/DIV knob is
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AP033 Active Differential Probe
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limited to the scale factors that can be obtained without changing the AP033 gain or
attenuation. Thus in Manual gain control mode, only the scale factor of the oscilloscope
will be changed. In this mode, dedicated touch screen controls are displayed for Probe
Attenuation and Probe gain (see Figure 5). The available values that appear in Probe
Attenuation will change depending on the presence of the external attenuator. When the
external ÷10 attenuator is not installed, ÷10 and ÷1 will be displayed. With the external
÷10 attenuator, only ÷100 will be displayed.
When using the AP033 with the ADPPS power supply on oscilloscopes without a ProBus
interface, use Table 2 to select the desired effective volts per division scaling.
Table 2, Recommended settings to obtain desired equivalent Volts/Division
Equivalent
Scale Factor
Oscilloscope
Scale Factor
AP033
Attenuation
AP033
Gain
Common
Mode
Range
Differential
Mode Range
Maximum
Offset
Input
Noise
(nV/√Hz)
100 μV/Div
1 mV/Div
÷1
×
10
±4.2 V
±40 mV
±400 mV
6
200 μV/Div 2 mV/Div ÷1 ×
10
±4.2 V ±40 mV ±400 mV 6
500 μV/Div
5 mV/Div
÷1
×
10
±4.2 V
±40 mV
±400 mV
6
1 mV/Div
10 mV/Div
÷1
×
10
±4.2 V
±40 mV
±400 mV
6
2 mV/Div 20 mV/Div ÷1 ×
10
±4.2 V ±40 mV ±400 mV 6
5 mV/Div
50 mV/Div
÷1
×10
±4.2 V
±40 mV
±400 mV
6
10 mV/Div
100 mV/Div
÷1
×
10
±4.2 V
±40 mV
±400 mV
6
20 mV/Div 20 mV/Div ÷10 ×
10
±42 V ±400 mV ±4 V 60
50 mV/Div
50 mV/Div
÷10
×10
±42 V
±400 mV
±4 V
60
100 mV/Div
100 mV/Div
÷10
×10
±42 V
±400 mV
±4 V
60
200 mV/Div
20 mV/Div
÷10
×
1
±42 V
±4 V
±4 V
115
500 mV/Div 50 mV/Div ÷10 ×
1
±42 V ±4 V ±4 V 115
1 V/Div
100 mV/Div
÷10
×1
±42 V
±4 V
±4 V
115
2 V/Div
20 mV/Div
÷1001
×
1
±42 V
±40 V
±40 V
1150
5 V/Div 50 mV/Div ÷100
1
×
1
±42 V ±40 V ±40 V 1150
10 V/Div
100 mV/Div
÷1001
×1
±42 V
±40 V
±40 V
1150
1. ÷100 attenuation is obtained using the external ÷10 attenuator. The probe is automatically set to ÷10
internally when the external attenuator is installed. The internal ÷1 attenuator cannot be selected when
the external ÷10 attenuator is installed.
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Operator’s Manual
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Adding Offset
The AP033 has true differential offset capability. This allows you to remove a DC bias
voltage from the differential input signal while maintaining DC coupling. By using probe
offset rather than offset at the oscilloscope inut, the full dynamic range of the probe
remains centered around the offset level. Add or remove offset using the oscilloscope
OFFSET controls.
Figure 6, Effect of Differential Offset
NOTE: In any software version later than legacy 8.1.0, the oscilloscope OFFSET
controls change the probe offset, rather than the offset at the oscilloscope input. The
OFFSET buttons on the probe body are disabled, although in Manual mode all other
buttons are functional.
In legacy software versions 8.0.0 and earlier, or when used with the ADPPS Power
Supply on instruments that lack ProBus support, probe offset must be controlled using
the OFFSET buttons on the probe body. The offset can be returned to zero by briefly
pressing the
↑
and
↓
OFFSET buttons at the same time.
AutoZero
The AP033 incorporates an AutoZero function to remove the DC offset from the output.
When power is first applied, the probe will return to the internal values resulting from the
last AutoZero cycle. After several minutes of warm up, or when the probe is exposed to a
large shift in ambient temperature, some DC offset drift may occur from thermal effects
in the amplifier circuitry. To adjust for this, manually invoke AutoZero.
CAUTION: Always remove the probe from the test circuit before initiating
AutoZero.
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