Agilent 1154A Users Guide

User’s Guide

Publication number 01154-92000 February 2000

For Safety information, Warranties, Regulatory information, and publishing information, see the pages at the back of this book.

All Rights Rese rved.

1154A 500 MHz Differential Probe

Contents

Inspect the Probe 3 1154A Differential Probes Introduction 4 Accessories 5 Attaching External Attenuators to the Probe 7

Specifications and Characteristics 8 To Connect the Probe to the Circuit under Test 12 Recommended Probe Configurations 14 Safety Considerations 17 Service Strategy 17 Performance Verification 18 Adjustment of 10:1 Attenuators 32 Performance Test Record 35

1154A 500 MHz Differential Probe

Inspect the Probe

❏ Inspect the shipping container for damage.

Keep a damaged shipping container or cushioning material until the contents of the shipment have been checked for completeness and the probe has been checked mechanically and electrically.

❏ Check the accessories.

Any accessories that were supplied with the probe are listed in “Accessories” on page 5.

• If the contents are incomplete or damaged, notify your Agilent Sales Office.

❏ Inspect the instrument.

• If there is mechanical damage or defect, or if the probe does not operate properly or pass performance tests, notify your Agilent Sales Office.

• If the shipping container is damaged, or the cushioning materials show signs of stress, notify the carrier as well as your Agilent Sales Office. Keep the shipping materials for the carrier’s inspection. The Agilent office will arrange for repair or replacement at Agilent’s option without waiting for claim settlement.

1154A 500 MHz Differential Probe

1154A Differential Probes Introduction

The 1154A is a wide-band differential active probe. The probe features low noise, low input capacitance, high common mode rejection, and Field Effect Transistor (FET) buffered inputs in the probe head. User-selectable offset gives the probe flexibility to measure a large range of signal types. Plug-on attenuators and AC coupling accessories further extend the application range. Included interconnect accessories 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" (0.635 mm) square pins, which provide a convenient low-cost method of creating device characterization test fixtures.

The 1154A is ideal for acquiring high speed differential signals such as those found in disk drive read channels, differential LAN, video, etc. 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.

Differential Amplifiers and CMRR

The 1154A Differential Probe is a high input impedance amplifier. A characteristic of differential amplifiers is the ability to reject signals that are common to the two inputs. The common mode rejection ratio (CMRR) is the measurement of this ability. It is expressed as the ratio between the amplitudes of the common mode and differential signals that produce equal outputs. These measurements can be referred to the probe input, if the differential gain is known. The CMRR is usually expressed in dB:

V common mode input Gain×



-------------------------------------------------------------------------

CMRR in dB 20

log=



V common mode output

The CMRR is only specified for unity Gain, therefore the gain term can be ignored in the equation shown above.

The ability to reject common mode signals depends on the balance designed into the probe amplifier. As the frequency of the common mode signal increases, it becomes harder to balance the amplifier parasitic parameters. This leads to degradation of the CMRR.

The CMRR of the 1154A Differential probe is specified from the probe tip. This method of specifying the probe CMMR eliminates the effects of source impedance, provided the connections from the probe tip to the signal source are symmetrical.

1154A 500 MHz Differential Probe

Accessories

The following diagram and table show the accessories supplied with the 1154A Differential Probe.

Probe Accessories

Item Description Qty. Part Number

1 AC coupler 1 01154-82101 2 10:1 Attenuator 1 01154-82102 3 Header 1 N/A 4 Offset Pin 4 N/A 5 0.5 Grabber 2 N/A 6 0.8 Grabber 3 N/A 7 Ground Wire 1 N/A 8 SMT Lead 4 N/A 9 Wire Lead 1 N/A

1154A 500 MHz Differential Probe

Accessories

To Order Replaceable Parts

To order a replaceable part, in the United States and Canada call our toll-free hotline at 1-877-447-7278, or call your local Agilent Technologies Sales Office.

Replaceable Parts

Item Description Qty. Agilent Part Number

1 AC coupler 1 01154-82101 2 10:1 Attenuator

3 Header 1 N/A 4 Offset Pin 4 N/A 5 0.5 Grabber 2 N/A 6 0.8 Grabber 3 N/A 7 Ground Wire 1 N/A 8 SMT Lead 4 N/A 9 Wire Lead 1 N/A

(includes an adjustment tool) Connection Kit 1 01154-60004

Trimmer Tool (0.635 mm square head)

1 01154-82102

1 5063-2196

Using the Accessories

The 1154A Differential Probe and accessories provide many ways to connect to circuitry under test. Any method used to connect the probe signal inputs to the circuit under test degrades the performance of the probing solution. Take the following precautions to optimize common mode rejection.

• Maintain tip connection lead length as short as possible and the same length.

• Follow the same path for wires used to connect the inputs of the probe to the circuit under test.

• Probes do not have infinite input impedance and therefore load the circuit under test. If the impedance of the test points is not identical, unequal loading will occur. This degrades the common mode rejection.

• The ground lead length is not usually critical with a differential probe.

• Carefully consider the ground potential relative to the oscilloscope ground potential. The potential difference must be within the common mode range of the probe.

• The DC potential between the AC coupling adapter and the oscilloscope ground must not exceed 42 Vpk.

• Do not cascade the external attenuators.

• Cascade the external AC coupling adapter in the following order: probe, attenuator, and AC coupling adapter.

1154A 500 MHz Differential Probe

Attaching External Attenuators to the Probe

Other Probe Accessories

The Agilent Wedge was designed to interface directly with the differential probe. These devices simplify connections to surface mount integrated circuits and have output pins compatible with the probe tip and attenuator sockets.

Attaching External Attenuators to the Probe

The external attenuators plug directly on to the probe tip. They are calibrated at the factory to provide the optimum common mode rejection and should not be swapped between probes.

1154A Attenuator Div-By-10 1 GHz

1154A AC Coupler Always Install Last

The 1154A probe’s best performance is achieved when the probe attenuation is set to /10 in the Infiniium’s Probes Setup dialog box.

1154A 500 MHz Differential Probe

Specifications and Characteristics

Performance Specifications

Input Configuration: Ground Connector True Differential (+ and inputs), with shield Effective Gain* X10, X1, LF Gain Accuracy X10 2% into Infinium 50 load measured at 1 kHz LF Gain Accuracy X1 2% into Infinium 50 load measured at 1 kHz LF Gain Accuracy 10 2% into Infinium 50 load measured at 1 kHz

Input Coupling DC/AC: Coupling obtained by installing AC Coupling

Maximum Input Voltage Either input from ground

CMRR (Unity Probe Gain) at 70 Hz: 80dB

AC coupling is obtained by installing the AC coupling adapter.

÷Ω

Adapter

± 42 V either input from ground

at 100 kHz: 80dB at 1 MHz: 60dB at 10 MHz: 40dB at 250 MHz: 14dB

X10, X100 (external attenuator)

÷÷

≥

–

Ω Ω

Range

Mode ÷ 1 internal

probe attenuation

Differential with 10X Gain ± 40 mV ± 400 mV ± 4V Differential with 1X Gain ± 400 mV ± 4 V ± 40 V Common ± 4.2 V ± 42 V ± 42 V

÷ 10 internal probe attenuation

÷ 100 internal probe attenuation

Range when using external ÷ 10 attenuator

Mode ÷ 10 internal

probe attenuation

Differential with 10X Gain ± 4 V Differential with 1X Gain ± 40 V Common ± 40 V

1154A 500 MHz Differential Probe

Specifications and Characteristics

Performance Characteristics

10 Attenuation)

Probe Bandwidth (Probe Only) (-3 dB)

Rise Time (Probe Only)

Input Resistance (Each Side to Ground)

Input Capacitance (Between Inputs) (No External Attenuators)

Input Capacitance (Each Side to Ground) (No External Attenuators)

Noise (Referred to Input, 5 - 1000 MHz)

DC to 500 MHz (

700 pS ( 10 Attenuation)

≤÷ ≤÷

875 pS ( 1 Attenuation)

1 M

Ω

1.6 pF (

≤÷

3.1 pF ( 1 Attenuation)

≤÷

3 pF ( 10 Attenuation)

≤÷

6 pF ( 1 Attenuation)

≤÷

6 nV Hz⁄ 10 nV Hz⁄

0 nV Hz⁄ ÷ 15 nV Hz⁄ ÷

Output Impedance 50 Nominal (Intended to Drive 50

Typical CMRR

ΩΩ

10 Attenuation)

( 1 Attenuation, 10X Gain)

( 1 Attenuation, 1X Gain)

( 10 Attenuation, 10X Gain)

( 10 Attenuation, 1X Gain)

1154A 500 MHz Differential Probe

Specifications and Characteristics

Typical Noise

Environmental Specifications

Operating Non-operating

Temperature 0 to 50 C -40 to 75 C Humidity Up to 80% RH at 40 C Up to 80% RH at 75 C Altitude Up to 4,600 meters

Vibration Random vibration 5 to 500 Hz,

Weight Approximately 226 g Dimensions Refer to the Dimensions drawing on page 11.

°°

(15,000 feet)

10 minutes per axis, 0.3 g

Up to 15,000 meters (50,000 feet)

Random vibration 5 to 500 Hz, 10 minutes per axis,

rms

2.41 g

. Resonant search 5 to

rms

500 Hz swept sine, 1 octave/min. sweep rate, (0.75 g), 5 minutes

resonant dwell at 4 resonance’s per axis.

Dimensions

1154A 500 MHz Differential Probe

Specifications and Characteristics

1154A 500 MHz Differential Probe

To Connect the Probe to the Circuit under Test

The method you use to connect the probe to the circuit under test is critical for accurate measurements. The following examples examine the effect of using different lengths of wire at 100MHz to connect the signal source to the probe tip.

Data taken at 100 MHz

Both inputs derived from a

Probe Input

Displayed Probe Output

common signal at the probe tip. CMRR = 43.5 dB

Both signals derived from a common signal via 5cm coupling lead.

CMRR = 29.8 dB

Both inputs derived from a common signal via leads of different length.

Positive input 5.3 cm. Negative input 7.5 cm.

CMRR = 28.1 dB

1154A 500 MHz Differential Probe

To Connect the Probe to the Circuit under Test

The Impedance of the Source

This is another instance where the symmetry of the differential circuit is important. The impedance of the source forms a network with the input impedance of the connection and the probe. This network determines the frequency response for the measurement. If each side of the differential source has a different impedance, the frequency response of each side will be different. This lack of balance is reflected in reduced CMRR. The higher the impedance of the source, the more critical these parasitic effects.

The Ground Connection

A poorly located ground connection allows ground loops to add to the common mode signal. The differential probe measures the potential difference between two locations on a PC board. Usually it is not necessary to ground the probe. Whether you ground the probe depends on the magnitude and frequency of the voltage difference between the oscilloscope ground and the board ground. It is good practice to maintain a board ground. Without this ground reference, you can easily exceed the common mode range of the probe.

Selecting the Best Mode of Operation

The 1154A probe has some unique features, allowing the probe to be optimized for many commonly encountered measurements. To apply these features, an

understanding of the probe’s block diagram is helpful.

1154A 500 MHz Differential Probe

ччччч

Recommended Probe Configurations

Probe Attenuation or Gain Within the probe tip of the 1154A is a selectable 10:1 passive attenuator. The control unit has a selectable gain of 1 or

10. This gives the following combinations of attenuation and gain.

Internal Probe Gain Internal Probe Attenuator Resultant Gain or

Attenuation

10 1 10 10 10 1 11 1 110 1/10

Note When the probe is switched from 1 to 10 there is a small change in probe

input impedance. The external 10 attenuator has been adjusted to give optimum performance when the internal probe attenuator is set to 10. When the Tip Adapters are used, there is some loss of CMRR. To obtain the maximum dynamic range, use the 10 adapter with the internal 10 attenuator. This is a significant advantage as the 10 Gain can be used in this mode, giving a

combined gain of only 10.

Recommended Probe Configurations

For best performance, use the following configurations. They are presented in the recommended order from the most desirable to the least.

Note The use of the ground connection is optional for all configurations.

Direct Connection

1154A Probe Tip

Test Point Layout

See the “Test Point Layout” section for more informa tion

1154A 500 MHz Differential Probe

Recommended Probe Configurations

AC Adapter/Attenuator

Use the attenuator shipped with the probe and marked with the same serial number for accurate measurements. Do not use the attenuators with other probes.

1154A Attenuator Div-By-10 1 GHz

1154A AC Coupler Always Install Last

Offset Pins

You may use offset pins with any of the tip adapters.

Offset Pins Rotate to Adjust Sp acing

SMT Lead

You may use SMT leads with any of the tip adapters.

Test Point Layout

See the “Test Point Layout” section for more information

SMT Leads Maintain Equal

Length

Solder Leads to Test Points

Ground

Ground Lead Opt

1154A 500 MHz Differential Probe

Recommended Probe Configurations

Wire Leads

You may use wire leads with any of the tip adapters.

Connec t Leads to Test Points

Ground

Opt

Grabbers

Using grabbers and wire leads results in significant lead length. Expect measurement quality degradation with fast signals.

0.5 mm or 0.8 mm Grabbers

Ground

Opt

Test Point Layout

1154A 500 MHz Differential Probe

Safety Considerations

Read the Safety summary in the warranty pages at the back of this guide before servicing the instrument. Before performing any procedure, review the safety information for cautions and warnings.

WARNING Trained service personnel aware of the hazard involved (for example, fire and

electric shock) should perform maintenance on the instrument. When

maintenance can be performed without power applied, the power cord must be removed from the instrument.

Service Strategy

To return the 1154A Differential Probe to optimum per formance requires factory repair. All probes must be returned to the service group for repair and calibration. If the probe is under warranty, normal warranty services apply. If the probe is not under warranty, you may exchange a failed probe for a reconditioned one at a nominal cost.

To Return the Probe to Agilent for Service

Call (877) 447-7278 for further details and the location of your nearest Agilent Service Office.

Write the following information on a tag and attach it to the probe.

• Name and address of owner.

• Probe model number.

• Probe serial number.

• Description of the service required or failure indications.

2 Return the following accessories with the probe:

• Attenuators

• AC coupling adapter

Retain all other accessories.

Return the probe in its case or pack the probe in foam or other shock absorbing material and place it in a strong shipping container.

You can use the original shipping materials or order materials from an Agilent Sales Office. If neither are available, place 3 to 4 inches of shock-absorbing material around the instrument and place it in a box that does not allow movement during shipping.

Seal the shipping container securely.

5 Mark the shipping container as FRAGILE.

In all correspondence, refer to the instrument by model number and full serial number.

1154A 500 MHz Differential Probe

Performance Verification

Use this procedure to verify the warranted characteristics of the 1154A Differential Probe. The recommended performance calibration interval for the 1154A is one year. Perform the complete performance verification procedure as the first step of annual certification. You can complete the performance verification without removing the probe covers. There are no user adjustments

available for calibration. Use the equipment shown in the “Test Equipment Required” section to complete the performance verification procedures.

Perform the steps listed in the “Preliminary Procedure” section on page 19.

2 Perform the steps listed in the “Test Gain Accuracy at 1kHz” section on

page 24.

3 Perform the steps listed in the “Test Offset” section on page 25. 4 Perform the steps listed in the “Test Differential Mode Range” section

on page 26.

5 Perform the steps listed in the “CMRR Test” section on page 27.

Test Equipment Required

Description Minimum Requirements Test Equipment

Infinium Oscilloscope 1.5 GHz 54845A Digital AC/DC Voltmeter DC: 0.1% accuracy

AC: 0.2% accuracy 200 mV @ 1 kHz 5 1/2 digit resolution

Function Generator Sine Wave and Square Wave output

Sine Wave Generator 50 MHz to 500 MHz BNC T Probe Tip BNC Adapter 5063-2143 Calibration Fixture 01154-63801 Intelligent Interface 01154-63401 10:1 resistor divider probe

(provided with the 54845A) Trimmer Tools

(included when attenuators are purchased separately)

waveforms

into 1 M

20 V

70 Hz to 10 MHz

10 M 1161A

Ω

Flat blade 0.04” (1 mm) wide Square Head 0.025” (0.635 mm) 5063-2196

Ω

34401A

33120A E4400B Option UNB

1154A 500 MHz Differential Probe

Performance Verification

Preliminary Procedure

Turn on the oscilloscope, the 1154A, and the other test equipment

described in the “Test Equipment Required” section on page 18.

Allow 30 minutes for all test equipment to warm up.

Press Default Setup.

3 Perform Probe Tip Cal on the 1161A connected to CH4 of the

oscilloscope (54845A).

4 Save the setup files listed below to the C drive of the 54845A.

These setups can also be saved to drive A and filed for future use.

Performance Verification Setup Files

Save the setup information shown below for the various performance verification tests to the specified file names on the C drive of the 54845A or to a floppy disk in drive A.

Setup for Differential Mode Range

File Name: 1154ACAL0

Probe Connected to CH1 1154A Probe Connected to CH4 1161A CH1 and CH4 Sensitivity 200 mV/div CH2 and CH3 Off Offset and Position CH1, CH2, CH3 and CH4 0 V Measurements: CH1 and CH4 V amplitude under Measure Voltage Timebase 500 Sec/div Timebase Delay 0 Sec Setup Acquisition Equivalent time: 8 averages Trigger CH4: level 0 V Probe First Test: Att 1; Gain 1

Second Test: Att 1/10; Gain 10

1154A 500 MHz Differential Probe

Performance Verification

Setup for CMRR at 70 Hz

File Name: 1154ACAL1

Probe Connected to CH1 1154A Probe Connected to CH4 1161A CH1 Sensitivity 2 mV/div CH4 Sensitivity 5 V/div CH2 and CH3 Off Offset and Position CH1, CH2, CH3 and CH4 0 V Timebase 10 mSec/div Timebase Delay 0 Sec Setup Acquisition Equivalent time: 64 averages Trigger CH4; level 0 V Probe Att 1; Gain 1

××

Setup for CMRR at 100 kHz

File Name: 1154ACAL2

Probe Connected to CH1 1154A Probe Connected to CH4 1161A CH1 Sensitivity 2 mV/div CH4 Sensitivity 5 V/div CH2 and CH3 Off Offset and Position CH1, CH2, CH3 and CH4 0 V Timebase 5 Sec/div Timebase Delay 0 Sec Setup Acquisition Equivalent time: 64 averages Trigger CH4: level 0 V + ve edge Probe Att 1; Gain 1

××

1154A 500 MHz Differential Probe

Performance Verification

Setup for CMRR at 1 MHz

File Name: 1154ACAL3

Probe Connected to CH1 1154A Probe Connected to CH4 1161A CH1 Sensitivity 10 mV/div CH4 Sensitivity 5 V/div CH2, CH3, and CH4 Off Offset and Position CH1, CH2, CH3 and CH4 0 V Timebase 500 nSec/div Timebase Delay 0 Sec Setup Acquisition Equivalent time: 64 averages Trigger CH4; level 0 V Probe Att 1; Gain 1

××

Setup for CMRR at 10 MHz

File Name: 1154ACAL4a

Probe Connected to CH1 None Probe Connected to CH4 1161A CH1 Sensitivity (50 ) 200 mV/div CH4 Sensitivity 200 mV/div CH2, CH3, and CH4 Off Offset and Position CH1, CH2, CH3 and CH4 0 V Timebase 100 nSec/div Timebase Delay 0 Sec Setup Acquisition Equivalent time: 64 averages Trigger CH4; level 0 V Probe Att 1; Gain 1

Ω

××

1154A 500 MHz Differential Probe

Performance Verification

Setup for CMRR at 10 MHz

File Name: 1154ACAL4b

Probe Connected to CH1 1154A Probe Connected to CH4 1161A CH1 Sensitivity 2 mV/div CH4 Sensitivity 200 mV/div CH2, CH3, and CH4 Off Offset and Position CH1, CH2, CH3 and CH4 0 V Timebase 100 nSec/div Timebase Delay 0 Sec Setup Acquisition Equivalent time: 64 averages Trigger CH4; 0 V + ve trig Probe Att 1; Gain 1

××

Setup for CMRR at 250 MHz

File Name: 1154ACAL5a

Probe Connected to CH1 None Probe Connected to CH4 1161A CH1 Sensitivity 200 mV/div CH2, CH3, and CH4 Off Offset and Position CH1, CH2, CH3 and CH4 0 V Timebase 2 nSec/div Timebase Delay 0 Sec Setup Acquisition Equivalent time: 64 averages Trigger CH4; 0 V + ve trig Probe Att 1; Gain 1

××

1154A 500 MHz Differential Probe

Performance Verification

Setup for CMRR at 250 MHz

File Name: 1154ACAL5b

Probe Connected to CH1 1154A Probe Connected to CH4 1161A CH1 Sensitivity 50 mV/div CH2, CH3, and CH4 Off Offset and Position CH1, CH2, CH3 and CH4 0 V Timebase 2 nSec/div Timebase Delay 0 Sec Setup Acquisition Equivalent time: 16 averages Trigger CH4: 0 V + ve edge Probe Att 1; Gain 1

××

1154A 500 MHz Differential Probe

Performance Verification

Test Gain Accuracy at 1kHz

Set up the test equipment as shown in the following diagram.

Select Auto Zero on the probe menu.

The probe tip must not be connected to a signal source when Auto Zero is performed.

Set the test equipment as shown in the following table.

Test Equipment Settings

Test Equipment Setting

Function generator frequency: 1 kHz

output amplitude: 200 mV offset: 0 V

Probe attenuator: 1 (See probe set up menu)

gain: 1:1 (See probe set up menu)

Sine Wave

RMS

3 Connect the probe tip to the probe input A of the calibration fixture. 4 Set the output of the function generator DVM (RMS mode) at the

calibration fixture to approximately 200 mV

RMS

(V1).

Record V1: ___________________ .

1154A 500 MHz Differential Probe

Performance Verification

5 Measure probe output with the same DVM at Intelligent Interface.

Record V2: ___________________ .

Calculate the % gain error.

(% Gain Error = 100(V2 - V1)/V1). Record % Gain Error: ___________________ .

Record the % Gain Error in the Performance Test Record on page 35.

8 Repeat steps 4 - 7. Use the following probe settings.

Probe Settings

Attenuator 1/10 (See probe set up menu) Gain 10 (See probe set up menu)

Test Offset

This is an important step in the performance verification process. You should perform it, even though no data is recorded in the Performance Test Record.

Disconnect the probe tip from the calibration fixture.

2 Set the probe gain to 1 using the Channel Set Up menu. 3 Select Auto Zero under the probe menu. 4 Measure the probe output (at BNC T of the Intelligent Interface) with

DVM DC mode.

Note The DVM reading should be approximately 2mV or less. This is not a warranted

specification.

1154A 500 MHz Differential Probe

Performance Verification

Test Differential Mode Range

Use setup file 1154ACAL0 for this test. Setup the test equipment as shown in the following diagram.

Press Default Setup.

2 Disconnect the intelligent interface. 3 Connect the 1154A to CH1 of the oscilloscope. 4 Load 1154ACAL0. 5 Connect the 1161A from BNC T (connected to the function generators

output) to CH4 of the oscilloscope.

6 Setup the test equipment as shown in the following table.

Test Equipment Setting

Function generator frequency: 1 kHz

output amplitude: 800 mV

7 Select Auto Zero under the probe menu.

Do not connect the probe tip or the function generator to the fixture when Auto Zero is performed.

Measure the amplitude on CH4.

1154A 500 MHz Differential Probe

Performance Verification

Connect a coaxial cable from BNC T (connected to the function generator) to Calibration fixture A.

10 Connect the 1154A probe tip to the calibration fixture. 11 Record “Pass” in the “Differential Mode Range” section of the

Performance Test Record on page 35 if no clipping occurs. Record “Fail” if visible clipping occurs.

12 Repeat steps 6 - 10. Use the following probe settings.

Probe Settings

Attenuator 1/10 (See probe set up menu) Gain 10 (See probe set up menu)

CMRR Test

Use setup files1154ACAL1 through 1154ACAL5b to perform the CMRR tests. Use the information in the following sections to test CMRR at 70 Hz, 100 kHz, 1 MHz, 10 MHz, and 250 MHz.

Set the test equipment as shown in the following diagram.

Test CMRR at 70 Hz Use setup file 1154ACAL1 in this test. Press Clear Display before starting each test. Wait for averaging to complete before taking

readings. If only a short time has elapsed from the last AUTO-ZERO calibration this step may be omitted.

1154A 500 MHz Differential Probe

Performance Verification

1 Set the function generator as shown in the following table.

Setting Value

Output Level 20 V Frequency 70 Hz Sine Wave

2 Load setup file 1154ACAL1. 3 Connect the 1161A to the function generator output and CH4 of the

oscilloscope.

4 Connect the 1154A probe to the CH C probe input of the calibration

fixture.

5 Set the 1154A probe gain and attenuation to 1. 6 Select Auto Zero under the probe menu.

Do not connect a signal to the probe tip of the fixture during Auto Zeroing.

Connect the function generator to Channel C BNC of the calibration fixture.

8 Measure the amplitude of the function generator output (CH4).

Record V1:_____________

Measure the amplitude of CH1.

The signal may be too small for an accurate reading. In this case, the reading obtained is less than that required to meet the CMRR specification.

Record V2:_____________

Calculate CMRR.

V2 amplitude



--------------------------------

CMRR 20

log=



V1 amplitude

11 Record CMRR in the “CMRR at 70 Hz” section of the Performance Test

Record on page 35.

Note CMRR must be 80dB or greater.

Test CMRR at 100 kHz Use setup file 1154ACAL2 in this test.

Set the function generator as shown in the following table.

Setting Value

Output Level 20 V Frequency 100 kHz Sine Wave Offset 0 V

2 Disconnect the function generator from the BNC calibration fixture. 3 Load setup file 1154ACAL2.

4 Perform Auto Zero under the probe menu.

Do not connect a signal to the probe tip of the calibration fixture during Auto Zeroing.

Connect the function generator to CHANNEL C BNC on the calibration fixture.

6 Measure the amplitude of the function generator output (CH4).

Record V1:_____________

Measure the amplitude of CH1.

Record V2:_____________

Calculate CMRR.

CMRR 20

9 Record CMRR in the “CMRR at 100 kHz” section of the Performance

Test Record on page 35.

Note CMRR must 80dB or greater.

Test CMRR at 1 MHz Use setup file 1154ACAL3 in this test.

Set the function generator as shown in the following table.

1154A 500 MHz Differential Probe

V2 amplitude



--------------------------------

log=



V1 amplitude

Performance Verification

Setting Value

Output Level 20 V Frequency 1 MHz

2 Disconnect the function generator from the BNC calibration fixture. 3 Load setup file 1154ACAL3. 4 Select Auto Zero under the probe menu.

Do not connect a signal to the probe tip of the calibration fixture during Auto Zeroing.

Connect the function generator to BNC C on the calibration fixture.

6 Measure the amplitude of the function generator output (CH 4).

Record V1:_____________

Measure the amplitude of CH1.

Record V2:_____________

Calculate CMRR.

CMRR 20

V2 amplitude



--------------------------------

log=



V1 amplitude

1154A 500 MHz Differential Probe

Performance Verification

9 Record CMRR in the “CMRR at 1 MHz” section of the Performance Test

Record on page 35.

Note CMRR must 60 dB or greater.

Test CMRR at 10 MHz Use setup files 1154ACAL4a and 1154ACAL4b in this test.

Set the signal generator as shown in the following table.

Setting Value

Output Level 5 dBm Frequency 10 MHz

2 Disconnect the 1154A probe from the CH1 and connect it to CH2 to

maintain a constant temperature.

3 Load setup file 1154ACAL4a. 4 Connect the signal generator to CH1 on the oscilloscope. 5 Measure the amplitude of the signal generator output.

Record V1:_____________

Remove the signal generator from CH1.

7 Remove the 1154A probe from CH2 and connect it to CH1. 8 Select Auto Zero under the probe menu.

Do not connect the probe tip to the calibration fixture during Auto Zeroing.

Connect the signal generator to BNC D of the calibration fixture.

10 Load setup file 1154ACAL4b. 11 Connect the 1154A probe to BNC D on the calibration fixture. 12 Measure the maximum value of CH1.

Record V2:_____________

Calculate CMRR.

CMRR 20

14 Record CMRR in the “CMRR at 10 MHz” section of the Performance

Test Record on page 35.

V2 amplitude



--------------------------------

log=



V1 amplitude

Note CMRR must 40 dB or greater.

1154A 500 MHz Differential Probe

Performance Verification

Test CMRR at 250 MHz Use setup files 1154ACAL5a and 1154ACAL5b in this test.

Set the signal generator as shown in the following table.

Setting Value

Output Level 5 dBm Frequency 250 MHz

2 Disconnect the 1154A probe from the CH1 and connect it to CH2 to

maintain a constant temperature.

3 Load setup file 1154ACAL5a. 4 Connect the signal generator to CH1 on the oscilloscope. 5 Measure the amplitude of the signal generator output.

Record V1:_____________

Remove the signal generator from CH1.

7 Remove the 1154A probe from CH2 and connect it to CH1. 8 Select Auto Zero under the probe menu.

Do not connect the probe tip to the calibration fixture during Auto Zeroing.

Connect the signal generator to BNC D of the calibration fixture.

10 Load setup file 1154ACAL5b. 11 Connect the 1154A probe to D on the calibration fixture. 12 Measure the maximum value of CH1.

Record V2:_____________

Calculate CMRR.

V2 amplitude



--------------------------------

CMRR 20

14 Record CMRR in the “CMRR at 250 MHz” section of the Performance

log=



V1 amplitude

Test Record on page 35.

Note CMRR must 14 dB or greater.

1154A 500 MHz Differential Probe

Adjustment of 10:1 Attenuators

A 10:1 attenuator is supplied with the 1154A probe. This attenuator is matched to the probe and should require no further adjustment. The attenuator is labeled with the last four digits of the probe serial number. Identify matching probes and attenuators using these numbers. If you purchase new attenuators for the probe, you must adjust them to match the probe.

Optimizing CMRR for an Attenuator

For optimum CMRR when the attenuator is connected to the probe, the DC and HF attenuation should be the same for both active inputs of the probe. Three trimmers are provided in the attenuator to match the two active inputs. The adjustments are located under the serial number label. Apply a new label after

calibration and mark this label with the last four digits of the probe’s serial number. You should only adjust an attenuator if it is not the original attenuator shipped with the probe.

You may remove the attenuator’s plastic covers. Take care not to damage the probe attenuator pins.

1154A 500 MHz Differential Probe

Adjustment of 10:1 Attenuators

10:1 Attenuator Adjustment Procedure

Use the following steps to adjust the 10:1 attenuator.

Connect the function generator, probe and oscilloscope as shown.

Connect the + active probe input to the function generator output for these tests. Connect the active input to ground with the probe ground socket.

–

Connect the 1154A Probe to CH1 of the oscilloscope.

3 Turn on the test equipment.

Allow 30 minutes for the probe to warm up.

Place the 10:1 attenuator on the 1154A probe.

Do not connect a signal to the probe at this time.

Set the function generator as shown in the following table.

Use a function with a flat top for this test.

Setting Value

Square Wave Output Amplitude 1 V Frequency 5 kHz Offset 0 V

Select Auto Zero on the probe menu.

Do not connect the probe tip to the calibration fixture during Auto Zeroing.

1154A 500 MHz Differential Probe

–

Adjustment of 10:1 Attenuators

Connect the 1154A probe as shown.

Use the clips to make these connections. The frequency being considered has a fundamental of 5kHz. Connect the + probe input to the signal source. Connect the probe input to ground.

–

Set the oscilloscope time base to 500 nS/div.

9 Press Auto Scale to set the 54845A to trigger off Ch4.

10 Use the square head trimmer tool to adjust the +LF comp to achieve the

best square corner and flat top of the displayed waveform.

Adjust so that the signal characteristics are correct when you remove the adjustment tool.

Connect the + and probe inputs to the function generator output while

–

the probe ground is connected to the function generator ground.

You can use the calibration fixture BNC to make these connections.

Set the function generator to 50 Hz and the output to 10 V amplitude.

The 1161A CH 4 will show this amplitude.

Set the oscilloscope time base to 5 mS/div.

14 Set Ch1 sensitivity to maximum. 15 Adjust DC attenuator balance for the minimum square wave amplitude.

The phase of the signal will change by 180 as you adjust the balance control through zero.

Set the function generator to 5 kHz and amplitude to 1 Vpp.

17 Connect the Probe input to the function generator’s output and the +

–

input to ground (calibration fixture BNC A).

Maintain the probe ground.

Press Auto Scale.

19 Use the square head trimmer tool to set the LF compensation for a

minimum of overshoot or undershoot at the leading edge of the waveform.

The correct adjustment is achieved when the wave-form has a flat top. Adjust so that the signal characteristics are correct when you remove the adjustment tool.

Set the oscilloscope time base to 500 nS/div.

21 Connect the probe + input and inputs to the function generator

–

output.

You may use BNC C on the calibration fixture. Connect the probe ground to the function generator ground.

Set the function generator as shown in the following table.

Setting Value

Amplitude 10 V Frequency 5 kHz

1154A 500 MHz Differential Probe

Performance Test Record

Set the oscilloscope sensitivity to maximum.

24 Use the square head trimmer tool to adjust the LF compensation for

–

minimum signal amplitude.

It is not possible to make the trace completely flat.

Performance Test Record

Agilent Technologies

Recommended Test Interval: 1 Year Recommended Date of Next Certification:_________ Certification Temperature:_____________________

1154A 500 MHz Differential Probe Serial No.:_______________________ Certification Date:_________________ Tested By:_______________________

_______________________________ _______________________________

Test Limit Minimum Results Limit Maximum

Accuracy at 1 kHz into 50 input of 54845A

Differential Mode Range Att 1; Gain 1

Att 10; Gain 10

CMRR at 70 Hz 80 dB N/A CMRR at 100 MHz 80 dB N/A CMRR at 1 MHz 60 dB N/A CMRR at 10 MHz 40 dB N/A CMRR at 250 MHz 14 dB N/A

Min Gain 98% Max Gain 102%

Ω

No Clipping

Pass

_____

Fail

N/A

1154A 500 MHz Differential Probe

Performance Test Record

DECLARATION OF CONFORMITY

according to ISO/IEC Guide 22 and EN 45014

Manufacturer’s Name: Agilent Technologies Manufacturer’s Address: Colorado Springs Division

declares, that the product

Product Name: Active Differential Voltage Probe Model Number(s): 1154A Product Option(s): All

conforms to the following Product Specifications:

Safety: IEC 1010-1:1990+A1 / EN 61010-1:1993

UL 3111 CSA-C22.2 No. 1010.1:1993

EMC: CISPR 11:1990 / EN 55011:1991 Group 1, Class A

IEC 555-2:1982 + A1:1985 / EN60555-2:1987 IEC 555-3:1982 + A1:1990 / EN 60555-2:1987 + A1:1991 IEC 801-2:1991 / EN 50082-1:1992 4 kV CD, 8 kV AD IEC 801-3:1984 / EN 50082-1:1992 3 V/m, {1kHz 80% AM, 27-1000 MHz} IEC 801-4:1988 / EN 50082-1:1992 0.5 kV Sig. Lines, 1 kV Power Lines

Supplementary Information:

The product herewith complies with the requirements of the Low Voltage Directive 73/23/EEC and the EMC Directive 89/336/EEC, and carries the CE-marking accordingly.

This product was tested in a typical configuration with Agilent test systems.

1900 Garden of the Gods Road Colorado Springs, CO 80907, U.S.A.

Colorado Springs, 1/12/2000

Ken Wyatt, Quality Manager

European Contact: Your local Agilent Technologies Sales and Service Office

Reproduction, ad aptation, or translation without prior written permission is prohib ited, except as allowed under the copyright laws.

Restric ted Rights Legend.

Use, duplication or disclo sure by the U.S . Government is subject to restrictions as set forth in subparagraph (c) (1) (ii) of the Rights in Technical Data and Computer Software clause at DFARS 252.2277013 for DOD agencies, and subparagraphs (c) (1) and (c) (2) of the Commercial Computer Software Restricted Rights clause at FAR 52.227-19 for other agencies.

Agilen t Technologies

3000 Hanover Street

Palo Alto, California 94304 U.S.A.

Document Warranty

The information contained in this document is subject to change without notice.

Agilent makes no warranty of any kind with regard to this material, including, but not limited to, the implied warranties of merchantability or fitness for a particular purpose.

Agilen t sha ll not be liabl e for errors contained herein or for damages in connection with the furnishing, perfo rmance, or use of this mate rial.

Product Warranty

This Agilent product has a warranty against defects in material and workmanship for a period of one year from date o f shipment. During the warranty period, Agilent Technologies will, at its option, either repair or replace products that prove to be defective.

For warranty service or repair, this product must be returned to a service facility designated by Agilen t.

For products retur ned to Agilent for warranty service, the Buyer shall prepay shipping charges to Agilent and Agilent shall pay shipping charges to return the product to the Buyer. However, the Buyer shall pay all shipping charges, duties, and taxes for products returned to Agilent from another country.

Agilent warrants that its software and firmware designated by Agilen t for use with an instrument will execute its programming instructions when properly installed on that instrument. Agilent does not warrant that the operation of the instrument software, or firmware will be uninterru pted or erro r free.

Limitation of Warranty

The for egoin g warranty shall not apply to defects resulting from improper or inadequate maintenance by the Buye r, Buyer-supplied software or interfacing, unauthorized modification or misuse, operation outside of the environ mental specifications for the product, or improper site preparation or maintenance.

No other warranty i s expressed or implied. Agilent specifically disclaims the implied warranties of merchantability or fitness for a particular purpose.

Exclusive Remedies

The remedies provided herein are the buyer's sole and exclusive remedies.

Agilent shall not be liable for any direct, indirect, special, incidental, or consequential damages, whether based on contract, tort, or any other legal theory.

Assistance

Product maintenance agreements and other customer assistance agreements are available for Agilent products .

For any assistance, contact your nearest Agilent Sales Office.

Certification

Agilent Technologies certifies that this product met its published specifications at the time of shipment from the factory. Agilent fur ther certifies that its cal ibrat ion measurements are traceable to the United States National Institute of Standards and Technology, to the extent allowed by the Institute's calib ration facility, and to the calibration facilities of other International S tandards Organization m embers.

Agilen t Technologies P.O. Box 2197 1900 Garden of the Gods Road Colorado Springs, CO 80901

Safety

This apparatus has been designed and tested in accordance with IEC Publication 1010, Safe ty Requirements for Measuring Apparat us, and has been supplied in a safe condition. To ensure safe operation and to keep the product safe, the information, cautions, and warnings in this operating manual must be heeded. In addition, note the external markin gs on the instrument that are described under "Safet y Symbols."

Safety Symbols

Instruction manual symbol: the product is marked with this symbol when it is necessary for you to refer to the instruction manual in order to protect against damage to the product.

Hazardous voltage symbol.

Earth terminal symbol: Used to indicate a circuit common connected to grounded chassis.

WARNING

The Warning sign denotes a hazard . It calls at tention to a procedure, practice, or the like, which, if not correctly performed or adhered to, could result in personal injury. Do not proceed beyon d a Warning sign until the indicated conditions are fully understood and met.

CAUTION

The Caution sign denotes a hazard . It calls at tention to an operating procedure, practice, or the like, which, if not correctly performe d or adhered to, could result in damage to or destruction of part or all of the product. Do not proceed beyond a Caution symbol until the indicated conditions are fully understood or met.

About this edition

This is the 1154A Differential Voltage Probe

User’s Guide.

Publication number 01154-92000, Feb. 2000

Printed in USA.

Print history is as follows:

01154-92000, Feb. 2000

New editions are complete revisions of the manual. Many product updates do not require manual changes; and, conversely, manual corrections may be done without accompanying product changes. Therefore, do n ot expect a one-to-one correspondence between product updates and manual updates.

Agilent Technologies Printed in the USA

Manual Part Number 01154-92000



Agilent 1154A Users Guide

Specifications and Main Features

Frequently Asked Questions

User Manual

Inspect the Probe

1154A Differential Probes Introduction

Differential Amplifiers and CMRR

Accessories

To Order Replaceable Parts

Using the Accessories

Attaching External Attenuators to the Probe

Other Probe Accessories

Specifications and Characteristics

To Connect the Probe to the Circuit under Test

The Impedance of the Source

The Ground Connection

Selecting the Best Mode of Operation

Recommended Probe Configurations

Direct Connection

AC Adapter/Attenuator

Offset Pins

SMT Lead

Wire Leads

Grabbers

Test Point Layout

Safety Considerations

Service Strategy

To Return the Probe to Agilent for Service

Performance Verification

Test Equipment Required

Preliminary Procedure

Performance Verification Setup Files

Test Gain Accuracy at 1kHz

Test Offset

Test Differential Mode Range

CMRR Test

Adjustment of 10:1 Attenuators

Optimizing CMRR for an Attenuator

10:1 Attenuator Adjustment Procedure

Performance Test Record

Agilent Technologies