Tektronix P7500 Series User manual

P7500 Series
TriMode™ Probes
Technical Reference

www.tektronix.com

071-2161-00

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supersedes that in all previously published material. Specifications and price change privileges reserved.

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Contacting Tektronix

Tektronix, Inc.
14200 SW Karl Braun Drive
P.O. B o x 5 0 0
Beaverton, OR 97077
USA

For product information, sales, service, and technical support:

In North America, call 1-800-833-9200.
Worl dwid e, vis it www.tektronix.com to find contacts in your area.

Warranty 2

Tektronix warrants that this product will be free from defects in materials and workmanship for a period of one (1)
year from the date of shipment. If any such product proves defective during this warranty period, Tektronix, at its
option, either will repair the defective product without charge for parts and labor, or will provide a replacement
in exchange for the defective product. Parts, modules and replacement products used by Tektronix for warranty
work may be ne
the property of Tektronix.

w or reconditioned to like new performance. All replaced parts, modules and products become

In order to o
the warranty period and make suitable arrangements for the performance of service. Customer shall be responsible
for packaging and shipping the defective product to the service center designated by Tektronix, with shipping
charges prepaid. Tektronix shall pay for the return of the product to Customer if the shipment is to a location within
the country in which the Tektronix service center is located. Customer shall be responsible for paying all shipping
charges, duties, taxes, and any other charges for products returned to any other locations.

This warranty shall not apply to any defect, failure or damage caused by improper use or improper or inadequate
maintenance and care. Tektronix shall not be obligated to furnish service under this warranty a) to repair damage
resulti
b) to repair damage resulting from improper use or connection to incompatible equipment; c) to repair any damage
or malfunction caused by the use of non-Tektronix supplies; or d) to service a product that has been modified or
integrated with other products when the effect of such modification or integration increases the time or difficulty
of servicing the product.

THIS WARRANTY IS GIVEN BY TEKTRONIX WITH RESPECT TO THE PRODUCT IN LIEU OF ANY
OTHER WARRANTIES, EXPRESS OR IMPLIED. TEKTRONIX AND ITS VENDORS DISCLAIM ANY
IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
TEKTR
AND EXCLUSIVE REMEDY PROVIDED TO THE CUSTOMER FOR BREACH OF THIS WARRANTY.
TEKTRONIX AND ITS VENDORS WILL NOT BE LIABLE FOR ANY INDIRECT, SPECIAL, INCIDENTAL,
OR CONSEQUENTIAL DAMAGES IRRESPECTIVE OF WHETHER TEKTRONIX OR THE VENDOR HAS
ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES.

btain service under this warranty, Customer must notify Tektronix of the defect before the expiration of

ng from attempts by personnel other than Tektronix representatives to install, repair or service the product;

ONIX’ RESPONSIBILITY TO REPAIR OR REPLACE DEFECTIVE PRODUCTS IS THE SOLE

Table of Contents

General Safety Summary .......................................................................................... v

Introduction ......................................................................................................... 1

Theory of Operation......... ................................ ................................ ....................... 3

Input Voltage

TriMode Operation ................... ................................ ................................ ......... 6

Probing Techniques to Maximize Signal Fidelity ..................... ................................ ..... 8

Input Impedance and Probe Loading ............... .................................. ...................... 15

Reference ....... ................................ .................................. ................................ .. 17

Single-Ended Measurements Using A and B Modes ..................... ................................ 17

Differentia

Serial Bus Standards...................................... ................................ .................... 21

Specifications ...... .................................. ................................ .............................. 22

Warranted Characteristics.................................................................................... 22

Typical Characteristics ....................... ................................ ................................ 23

Nominal Characteristics...................................................................................... 25

Tip Specifica

User Service ........................................................................................................ 35

Error Condition . . . ..... . ..... . ..... . ..... . ..... . ..... . ..... . .... . . .... . . .... . ..... . ..... . ..... . ..... . ..... . ... 35

Replaceable Parts ............................................................................................. 36

Preparation for Shipment .................. ................................ .................................. 48

Limits.................................... .................................. ..................... 3

l Measurements................................................................................... 19

tions............................................................................................. 26

P7500 TriMode Probe Family Technical Reference i

Table of Contents

List of Figure

Figure 1: Operating voltage window ...................... ................................ ....................... 4

Figure 2: Dynamic range versus linearity, 5X range ........................ ................................ ... 5

Figure 3: Dynamic range versus linearity, 12.5X range........................... ............................. 5

Figure 4: TriMode input structure ................................................................................ 7

Figure 5: P75TLRST TriMode Long Reach Solder Tip. .................................. ..................... 8

Figure 6: Typical wire length from probe tip to circuit......................................................... 9

Figure 7: P75TLRST solder tip with 0.010 in. of tip wire.................. .................................. 10

Figure 8: P75TLRST solder tip with 0.050 in

Figure 9: P75TLRST solder tip with 0.100 in. of tip wire.................. .................................. 11

Figure 10: P75TLRST solder tip with 0.200 in. of tip wire .................................................. 11

Figure 11: P75PDPM Precision Differential Probing Module ............................................... 12

Figure 12: P75PDPM with short ground spring, 0.030 in. spacing.......................................... 13

Figure 13: P75PDPM with short ground spring, 0.050 in. spacing.......................................... 13

Figure 14: P75PDPM with short ground spring, 0.090 in. spacing.......................................... 14

Figure 15: P75PDPM with short ground spring, 0.180 in. spacing.......................................... 14

Figure 16: TriMode probe input model ......................................................................... 15

Figure 17: Embedded probe fixture ....................... ................................ ...................... 16

Figure 18: Typical channel isolation for P7500 Series TriMode probes .................................... 18

Figure 19: Simplified model of a differential amplifier ....................................................... 19

Figure 20: Typical CMRR for P7500 Series TriMode probes................................................ 20

Figure 21: Probe body and control box dimensions ........................................................... 24

Figure 22: P75TLRST TriMode Long Reach Solder Tip dimensions....................................... 26

Figure 23: P7513 probe with the P75TLRST solder tip....................................................... 27

Figure 24: P7516 probe with the P75TLRST solder tip....................................................... 27

Figure 25: P75TLRST differential impedance versus lump-element equivalent........................... 28

Figure 26: P75TLRST common-mode impedance ............................................................ 28

Figure 27: P75TLRST bandwidth

Figure 28: P75TLRST bandwidth on a P7516 probe.......................... ................................ 29

Figure 29: P75PDPM Precision Differential Probing Module dimensions ................................. 30

Figure 30: P7513 probe with the P75PDPM probing module................................................ 31

Figure 31: P7516 probe with the P75PDPM probing module................................................ 31

Figure 32: P75PDPM differential impedance versus lump-element equivalent.. .......................... 32

Figure 33: P75PDPM bandwidth on a P7513 probe........................................................... 32

Figure 34: P75PDPM bandwidth on a P7516 probe........................................................... 33

Figure 35: Removing the bullets................................................................................. 37

Figure 36: Installing the bullets.. . . ..... . ..... . ..... . ... . . . .... . ..... . ..... . ..... . ..... ..... . ..... . ..... . ..... . .. 38

Figure 37: Large and small springs installed ..................... ................................ .............. 40

Figure 38: Set the gap....................... ................................ ................................ ...... 41

s

. of tip wire...................................... .............. 10

on a P7513 probe.......................... ................................ 29

ii P7500 TriMode Probe Family Technical Reference

Table of Contents

Figure 39: Inse

Figure 40: Transfer spring from tip to tool ..................................................................... 42

Figure 41: Place spring on tool .................................................................................. 43

Figure 42: Set spring in front seat ............................................................................... 43

Figure 43: Set the spring in the rear seats....................................................................... 44

Figure 44: Properly seated spring................................................................................ 44

Figure 45: Dis

Figure 46: Probing module tips.................................................................................. 45

Figure 47: Removing the tip ..................................................................................... 46

Figure 48: Separating the tip board pair ........................................................................ 46

Figure 49: Seating the tip in the top tabs.................................. .................................. .... 47

Figure 50: Snapping the tip into the bottom tabs .............................................................. 47

rt tool beneath spring............................................................................ 41

connecting the tip cable.............................. ................................ ............ 45

P7500 TriMode Probe Family Technical Reference iii

Table of Contents

List of Tables

Table 1: Offset ranges....................... .................................. ................................ .... 17

Table 2: Seri

Table 3: Warranted electrical characteristics ... .................................. .............................. 22

Table 4: Typical electrical characteristics. ................................ .................................. .... 23

Table 5: Typical mechanical characteristics.................................................................... 24

Table 6: Nominal electrical characteristics ........................... .................................. ........ 25

Table 7: TriMode probes replaceable parts ..................................................................... 36

Table 8: Requ

al bus standards with dynamic range requirements............................................. 21

ired equipment....................... ................................ .............................. 36

iv P7500 TriMode Probe Family Technical Reference

General Safety Summary

General Safet

To Avoid Fire or Personal

Injury

ySummary

Review the fol
this product or any products connected to it.

To avoid pote

Only qualified personnel should perform service procedures.

While using this product, you may need to access other parts of a larger system.
Read the safety sections of the other component manuals for warnings and
cautions re

Connect and Disconnect Properly. Connect the probe output to the measurement
instrument before connecting the probe to the circuit under test. Connect the
probe reference lead to the circuit under test before connecting the probe input.
Disconnect the probe input and the probe reference lead from the circuit under test
before d

Observe All Terminal Ratings. To avo id fire or shock hazard, observe all ratings
and mark
information before making connections to the product.

Do not a
exceeds the maximum rating of that terminal.

lowing safety precautions to avoid injury and prevent damage to

ntial hazards, use this product only as specified.

lated to operating the system.

isconnecting the probe from the measurement instrument.

ings on the product. Consult the product manual for further ratings

pply a potential to any terminal, including the common terminal, that

Do Not O

removed.

Do Not

product, have it inspected by qualified service personnel.

Avoid

when power is present.

Do No

Do Not Operate in an Explosive Atmosphere.

Keep Product Surfaces Clean and Dry.

perate Without Covers. Do not operate this product with covers or panels

Operate With Suspected Failures. If you suspec t that there is damage to this

Exposed Circuitry. Do not touch exposed connections and components

t Operate in Wet/Damp Conditions.

P7500 TriMode Probe Family Technical Reference v

General Safety Summary

TermsinthisManual

Symbols and Terms on the

Product

These terms may

WARNING. Warning statements identify conditions or practices that could result

in injury or loss of life.

CAUTION. Caution statements identify conditions or practices that could result in

damage to this product or other property.

These terms may a ppear on the product:

DANGER ind
the marking.

WARNING i
read the marking.

CAUTION i

The following symbol(s) may appear on the product:

appear in this manual:

icates an injury hazard immediately accessible as you read

ndicates an injury hazard not immediately accessible as you

ndicates a hazard to property including the product.

vi P7500 TriMode Probe Family Technical Reference

Introduction

This manual discusses topics that are not covered in depth in the P7500 Series
TriMode Probes Quick Start User Manual.

The main sections are:

Theory of Operation — Contains probe details not covered in the user manual.

Reference — Co
to increase measurement accuracy.

Specificatio
the probe and probe tip accessories.

User Servic

ntains information about differential measurements and how

ns — Contains warranted, typical, and nominal characteristics for

e — Describes troubleshooting and probe maintenance.

P7500 TriMode Probe Family Technical Reference 1

Introduction

2 P7500 TriMode Probe Family Technical Reference

Theory of Operation

This section discusses operating considerations and probing techniques. For more
detailed information a bout differential measurements and TriMode operation,
refer to Refe

The P7500 Series TriMode probes are optimized for high bandwidth; they
are not gener
characteristics and access to dense circuitry, and must be handled carefully.

CAUTION. To prevent damage to the probe, use care when handling the probe.

Rough or careless use can damage the probe.

Input Voltage Limits

The P7500 Series TriMode probes are designed to probe low-voltage circuits.
Before pr
the operating voltage window, and the differential-mode signal range. (See
Table 4 on page 23.)

rence. (Seepage17.)

al-purpose probes. The probe tips are miniaturized for electrical

obing a circuit, take into account the limits for maximum input voltage,

Maximum Input Voltage

The max
withstand without damaging the probe input circuitry.

CAUTION. To avoid damaging the inputs of the probes, do not apply more than

±15 V (DC + peak AC) between each input or between either probe input and
ground.

CAUTION. To avoid ESD damage to the probe, always use an antistatic wrist

strap (provided with your probe), and work at a static-approved workstation when
you handle the probe.

imum input voltage is the maximum voltage to ground that the inputs can

P7500 TriMode Probe Family Technical Reference 3

Theory of Operation

Operating Voltage Window

The operating v
to each input, with respect to earth ground, without saturating the probe input
circuitry. (See Figure 1.) A common-mode voltage that exceeds the operating
voltage window may produce an erroneous output waveform even when the
differential-mode specification is met.

Figure 1: Operating voltage window

oltage window defines the maximum voltage that you can apply

Differential-Mode Signal

Range

Offset Voltage Range

The differential-mode signal range is the maximum voltage difference between
the A and B inputs that the probe can accept without distorting the signal. The
distortion from a voltage that exceeds this maximum can result in a clipped or
otherwise inaccurate measurement. The P7500 Series probes have two attenuation

ngs, 5X and 12.5X, that allow dynamic range to be traded off against signal

setti
noise. The 12.5X attenuator setting has the largest dynamic range; the 5X
attenuator setting has the lowest noise. The following two graphs illustrate the
linearity error over the dynamic voltage range of the probes in both attenuation
settings.

The Offset Voltage Control, accessible from the attached oscilloscope user
interface, allows the probe dynamic range to be effectively moved up and down
within the limits of the offset voltage range and the operating voltage window.
When the offset voltage is set to zero volts and the input signal is zero volts

nputs shorted to ground, not open), the displayed signal should be zero volts.

(i
If a noticeable zero volt offset is present under the a bove conditions, a Probe
Cal operation should be performed. (See the P7500 Series Probes Quick Start
User Manual).

4 P7500 TriMode Probe Family Technical Reference

Figure 2: Dynamic range versus linearity, 5X range

Theory of Operation

Figure 3: Dynamic range versus linearity, 12.5X range

P7500 TriMode Probe Family Technical Reference 5

Theory of Operation

TriMode Opera

tion

The TriMode feature of the new P7500 Series probe family is designed for
improved convenience and enhanced capability in measuring differential
signal quali
single-ended signals, full characterization of differential signal quality requires
more than a simple differential measurement. A TriMode probe features three
Input Modes that allow a differential signal to be fully characterized with four
measurements: differential, positive polarity and negative polarity single-ended,
and common mode.

A TriMode probe provides improved efficiency and convenience by enabling full
differential signal characterization from a single soldered connection. Using the
P75TLRST
signals (the A signal and the B signal) and a ground reference. From this single
DUT (device under test) connection, the internal electronic switching control
of the TriMode probe allows any one of the three probe Input Modes (four
measurements) to be selected at a time. The TriMode probe inputs are routed on
the probe ASIC (application-specific integated circuit) to a set of four independent
input a

A – B (for differential signal measurement)

A – GND (for positive polarity single-ended measurement)

ty. Since a differential signal is composed of two complementary

probe tip, probe connections are soldered to the two c omplementary

mplifiers that perform the following signal calculations:

B – GND (for negative polarity single-ended measurement)

[A+B]/2 - GND (for common mode measurement)

The four input amplifiers are multiplexed together and only the selected Input
Mode function is output to the connected scope. (See Figure 4 on page 7.) The
figure shows a conceptual view of the TriMode probe input structure, where the
C input provides the probe ground reference and is connected to the probe tip
ground interconnect using the probe tip cable coaxial shields.

6 P7500 TriMode Probe Family Technical Reference

Theory of Operation

Figure 4: TriMode input structure

The TriMode features are controlled by the probe Control Box switches, which
allow os
probe Input Mode.

On futur
probe GUI can perform a Probe Cal operation on all Input Modes and Attenuation
Settings at once using the TriMode Probe Cal fixture that is supplied with P7500
Series probes. Full TriMode support will also allow storage and automatic recall
of relevant settings like Offset. For more information about oscilloscopes that
feature full TriMode support, contact Tektronix.

cilloscope features like Probe Cal to be exercised only for the selected

e oscilloscopes that provide full TriMode support, the scope-controlled

P7500 TriMode Probe Family Technical Reference 7

Theory of Operation

Probing Techn

iques to Maximize Signal Fidelity

P7500 TriMode Long Reach

Solder Tip (P75TLRST)

Signal fidelity is an indication of how accurately a probe represents the signal
being measured. The signal fidelity of the probe is best when the probe is
applied prop
connecting the P7500 probe tips are given in the following section.

The P75TLRST probe tip is designed for solder-down probing applications. It
is composed of a small form factor interconnect circuit board with SMD0402
damping resistors and a set of vias for wire attachment to the DUT. The circuit
board vias are designed for both 4 mil and 8 mil wire and a special high tensile
strength wire is supplied as part of the wire accessory kit. The expanded view of
the probe tip shows the location of the A and B signal inputs as well as the two
ground reference connections. (See Figure 5.)

erly to the circuit with the P7500 probe tips. Recommendations for

Figure 5: P75TLRST TriMode Long Reach Solder Ti

Attached to the circuit board are a pair of very low skew (<1ps) coaxial cables and
a polarized G3PO dual connector block. The G3PO connector block of the probe
tip is inserted into the input nose piece on the end of the probe body of the P7500
family probes. The probe body contains a mating, polarized G3PO connector
block with attached G3PO connector b ullets.

The connector bullets are a part of the G3PO connector design, providing a
self-aligning interconnect mechanism between G3PO connectors. The G3PO
connector in the probe body is designed to have higher detent force than the probe
tip connectors, which is intended to ensure that the G3PO bullets remain in the
probe body connector when disconnected. The probe body nose piece, with its
integral spring mechanism, helps to provide a self-aligning mechanism for hand
insertion of the probe tip. The probe body nose springs also give a secure capture
of the probe tip connector after insertion. Release of the probe tip is assisted by
using the wire-connected cable release holder on the probe tip connector. This
probe tip release holder should always be used rather than pulling on the probe tip
cables, which may cause tip cable damage.

The recommended wire attachment method is to first solder the wires to the DUT,
being careful to minimize the wire length of the signal and ground connections.
This is followed by threading the wires through the probe tip board vias, being

p

8 P7500 TriMode Probe Family Technical Reference