The servicing instructions are for use by qualified
personnel only. To avoid personal injury, do not
perform any servicing unless you are qualified to
do so. Refer to all safety summaries prior to
performing service.
Tektronix products are covered by U.S. and foreign patents, issued and
pending. Information in this publication supercedes that in all previously
published material. Specifications and price cha nge privileges reserved.
Tektronix, Inc., P.O. Box 500, Beaverton, OR 97077
TEKTRONIX, TEK, TEKPROBE, and SureFoot are registered trademarks of
Tektronix, Inc. KlipChip is a trademark of Tektronix, Inc.
WARRANTY
Tektronix warrants that the products that it manufactures and sells will be free from defects
in materials and workmanship for a period of one (1) year from the date of shipment. If a
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.
In order to obtain service under this warranty, Customer must notify Tektronix of the
defect before the expiration of 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 resulting from attempts by personnel other
than Tektronix representatives to install, repair or service the product; 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 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. TEKTRONIX’ RESPONSIBILITY
TO REPAIR OR REPLACE DEFECTIVE PRODUCTS IS THE SOLE 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.
Table of Contents
General Safety Summaryv..............................
Service Safety Summaryvii..............................
Review the following safety precautions to avoid injury and prevent
damage to this product or any products connected to it. To avoid
potential hazards, use this product only as specified.
To Avoid Fire or Personal Injury
Connect and Disconnect Properly. Connect the probe output to the
measurement instrument before connecting the probe to the circuit
under test. Disconnect the probe input and the probe ground from the
circuit under test before disconnecting the probe from the measurement instrument.
Observe All Terminal Ratings. To avoid fire or shock hazard, observe all
ratings and markings on the product. Consult the product manual for
further ratings information be fore making connections to the product.
The common terminal is at ground potential. Do not connect the
common terminal to elevated voltages.
Do Not Operate Without Covers. Do not operate this product with
covers or panels removed.
Do Not Operate With Suspected Failures. If you suspect there is damage
to this product, have it inspected by qualified service personnel.
Only qualified personnel should perform service procedures. Re ad
this Service Safety Summary and the General Safety Summary before
performing any service procedures.
Do Not Service Alone. Do not perform internal service or adjustments
of this product unless another person capabl e of rendering fi rst aid
and resuscitation is present.
Department or name (if known)
14200 SW Karl Braun Drive
P.O. Box 500
Beaverton, OR 97077
USA
Web sitewww.tektronix.com
Sales
support
Service support
Technical
support
*This phone number is toll free in North America. After office
hours, please l eave a voice mail message.
Outside North America, contact a Tektronix sales office or
distributor; see the Tektronix web site for a list of offices.
The P6330 is a high-bandwidth (3.5 GHz) active differential probe
with a miniaturized probe head design. The probe has low circuit
loading, high common-mode rejection, and comes with a variety of
accessories for connecting to surface-mount devices and othe r
components.
The P6330 probe uses the TEKPROBE interface, which provides
power, selects the correct display scaling, and automatical ly sets the
50 Ω termination on the oscilloscope input. The TEKPROBE
interface is standard on many Tektronix TDS series oscilloscopes.
The Tektronix 1103 TEKPROBE Power Supply can be used for
instruments without the TEKPROBE interface (refe r to page 7).
Table 1 shows the features and standard accessories of the P6330
differential probe.
Table 1: P6330 features and standard accessories
Feature/AccessoryDescription
TEKPROBE interface. The TEKPROBE interface supplies
power to the probe, selects the correct display scaling, and
automatically sets the 50 Ω termination on the oscilloscope input.
If your oscilloscope does not have the TEKPROBE interface, you
can use the optional 1103 power supply (refer to page 7).
Input connections. The plus and minus connections of the probe
head accept the standard and optional probe accessories (some
+
--
Ground
of which connect through the square pin adapter).
WARNING: Skin penetration hazard. To prevent injury, install the
probe tip cover when the probe is not in use. The probe tips are
extremely sharp to ensure good contact and measurement
integrity.
Probe tip cover. The probe tips are extremely sharp to ensure
good contact and measurement integrity. When not using the
probe, slide the probe tip cover over the probe head to prevent
damage to the probe tips and to protect yourself from personal
injury.
Tektronix part number: 200-4236-00
Three-inch ground lead (2 ea). Use the ground lead for
connecting the probe ground to the circuit, if needed. The
socketed end of the lead may be connected to accessories, or
fitted onto 0.025-inch pins.
Table 1: P6330 features and standard accessories (Cont.)
Feature/AccessoryDescription
Variable spacing adapter (4 ea). The variable spacing adapter
fits over the probe tip. Push the adapter onto the probe tip until it
seats against the probe head.
Use the variable spacing adapter to probe any two adjacent leads
or test points spaced between 0.020 and 0.180-inches apart.
Adjust the articulated pins by gently rotating them using a pair of
tweezers.
NOTE: The articulated pins can be bent, but they are fragile. Use
extreme care when bending the pins.
The elastomeric contacts inside the adapter are rated for 50 -- 75
insertion cycles with the probe tip. Replace the adapter after
Seated
against
probe head
exceeding these limits to avoid unreliable operation.
Tektronix part number: 016-1885-00 (package of 4)
Seated
against
probe head
Square pin adapter (4 ea). Push the square pin adapter onto the
probe tip until it seats against the probe head. Use the square pin
adapter to connect the probe to other accessories, such as the
Y-lead adapter or TwinFoot adapter. The inputs on the adapter
are spaced 0.100-inches apart.
CAUTION: To avoid damaging the square pin connectors, do not
insert anything larger than a 0.025-inch square pin into the inputs.
The elastomeric contacts inside the adapter are rated for 50 -- 75
insertion cycles with the probe tip. Replace the adapter after
exceeding these limits to avoid unreliable operation.
Table 1: P6330 features and standard accessories (Cont.)
Feature/AccessoryDescription
TwinFoot adapter (4 ea). Use the TwinFoot adapter to probe two
adjacent leads on a surface-mount integrated circuit. The
TwinFoot adapter connects to the probe through the square pin
adapter. Flexible fingers adapt to a range of lead spacings. See
Figure 4 on page 12.
Tektronix part number: 016-1785-00 (package of 4)
Y-lead adapter (2 ea). The Y-lead adapter connects to the probe
through the square pin adapter. The socketed ends of the leads
may be connected to the probe tips and accessories, or fitted onto
0.025-inch pins.
Color marker bands
Tektronix part number: 196-3468-00 (package of 2)
X-lead adapter (2 ea). The X-lead adapter connects between
accessories fitted with 0.025-inch pins, such as the SMT KlipChip
and Micro KlipChip adapters.
You can use the X-lead adapter with the adapters below to make
connections between the probe tip and your circuit under test.
Be aware of the electrical effects of the added lead length of the
adapters, especially as circuit frequencies increase.
Tektronix part number: 196-3473-00 (package of 2)
SMT KlipChip adapter (2 ea). Use this accessory to probe the
leads on dual-in-line packages (DIP). The 0.025-inch pins
recessed in the adapter body may be connected to the X- and
Y-lead adapters, and the 3-inch ground leads.
Tektronix part number: 206-0364-XX
Color marker bands (10 ea). Attach matching pairs of the color
marker bands onto the cable at the head and compensation box
of each probe. The marker bands enable quick verification of
which probe is connected to which instrument channel.
Tektronix part number: 016-1315-00 (package of 10)
Table 1: P6330 features and standard accessories (Cont.)
Feature/AccessoryDescription
Plastic accessory box. Use the plastic box to store the probe
accessories when not in use.
Tektronix part number: 006-7164-00
Instrument case. The instrument case protects the probe from
harsh environments and provides room for storing optional
accessories.
Tektronix part number (P6330): 016-1879-00
Calibration certificate. A certificate of traceable calibration is
provided with every instrument shipped.
Instruction Manual. Provides instructions for operating the
P6330 differential probe and procedures for verifying the
performance, adjusting, and maintaining the probe.
Tektronix part number: 071-0757-XX
Accessory reorder sheet.
The accessory reorder sheet provides photos and part numbers
for identifying standard and optional accessories that are
compatible with your probe.
Tektronix part number 001-1327-XX
Antistatic wrist strap. When using the probe, always work at an
antistatic work station and wear the antistatic wrist strap.
Table 2 shows the optional accessories that you can order for the
P6330 differential probe.
Table 2: Optional accessories
AccessoryDescription
Release tool. Use for opening the compensation box to access
adjustments.
Order Tektronix part number 003-1383-00
Adjustment tool. Use for making internal adjustments to the
probe.
Product Features and Accessories
Order Tektronix part number 003-0675-01
Probe calibration fixture. Use the probe calibration fixture to
perform some of the calibration procedures. The calibration fixture
connects to signal sources used to test the probe characteristics.
Refer to page 39 for details on using the fixture.
Order Tektronix part number 067-0419-XX
1103 Power supply. Order the 1103 power supply for
performance verification procedures, and for instruments that do
not have the TEKPROBE Interface. Power cord options are
available for the following countries or regions.
50 Ω termination. Terminates the output of the 1103 power
supply to the required 50 Ω if the oscilloscope does not have a
50 Ω input setting. Order Tektronix part number 011-0049-01.
50 Ω BNC cable. Connects to the 1103 output.
Order Tektronix part number: 012-0076-00
IEEE1394 Adapter. The IEEE1394 Adapter allows you to probe
signals on the bus, external to system enclosures, without
disturbing system operation. The adapter maintains a balanced
55 Ω signal path and can be used in both single-ended and
differential modes.
Order Tektronix part number: 679-5027-00
Micro KlipChip adapters (2 ea). Use the adapters to probe the
leads on integrated circuits that are surface-mounted. The
0.025-inch pin at the back of the adapter may be connected to the
X- and Y-lead adapters, and the 3-inch ground leads.
This section discusses operating considerations and probing
techniques. For more detailed information about differential
measurements and common-mode rejection ratio (CMRR), see the
Reference sectiononpage19.
The P6330 probe design is optimized for high bandwidth, low
capacitance applications; it is not a general purpose probe. The probe
head and tips are miniaturized for electrical characteristics and
access to dense circuitry, and must be handled carefully. Rough or
careless use will likely damage the probe.
To avoid damaging the probe tips, minimize your lateral pressure on
the tips. Always probe as directly straight onto the circuit (perpe ndicular) as possible. The probe tips are extremel y sharp to ensure good
contact and measurement integrity.
WARNING. Skin penetration hazard. Use care when handling the
probe. To prevent injury and/or probe damage, install the protec tive
cover over the probe tips when the probe is not in use.
Installation
Before you connect the output of the P6330 differential probe,
determine whether or not your oscilloscope has a TEKPROBE
interface. See Figure 2 on page 10.
Instruments with the TEKPROBE Interface (Tektronix TDS 400, 500, 600,
and 700 Series Oscilloscopes)
On instruments that have the TEKPROBE interface, simply connect
the probe to the input. The TEKPROBE interface provides power,
selects the correct display scaling, and automatically sets the 50 Ω
termination on the oscilloscope input.
NOTE. TDS 400 and TDS 400A series oscilloscopes do not interpret
the scale factor coding of the P6330 differential probe. To correct for
this problem, divide the measurement (or scale factor) by 5.
Instruments without the TEKPROBE Interface
On instruments that do not have the TEKPROBE interface, you must
order the optional 1103 power supply (refer to page 7). Each 1103
can supply power for two probes. The input of the osc illoscope must
also terminate into 50 Ω. Refer t o page 22 for informat ion on the
effects of extending the output of the probe.
Input Voltage Limits
The P6330 differential probe is designed to probe low-voltage
circuits. Before probing a voltage, take into account the limits for
maximum input voltage, the common-mode signal range, and the
differential-mode signal range. For specific limits, see Specifications
on page 25.
The maximum input voltage is the maximum voltage to ground that
the inputs can withstand without damaging the input circuitry of the
probe.
CAUTION. To avoid damaging the inputs of the P6330 differential
probe, do not apply more than ± 15 V (DC + peak AC) between each
input and ground.
Common-Mode Signal Range
The common-mode signal range is the maximum voltage that you
can apply to each input, with respect to earth ground, without
saturating the input circuitry of the probe. A common-mode voltage
that exceeds the common-mode signal range may produce an
erroneous output waveform even when the differential-m ode
specification is met. For Specifications, refer to page 25.
Differential-Mode Signal Range
The differential-mode signal range is the maximum voltage
difference between the plus and minus inputs that the probe can
accept without distorting the signal. The distortion from a volta ge
that is too large can result in a clipped or otherwise distorted and
inaccurate measurement. For Specifications, refer to page 25.
Common-Mode Rejection
The common-mode rejection ratio (CMRR) is the ability of a probe
to reject signals that are common to both inputs. More prec isely,
CMRR is the ratio of the differential gain to the common-mode gain.
The higher the ratio, the greater the ability to reject common-mode
signals.
Common-mode rejection decreases as the i nput frequency increases.
Figure 11 on page 28 is a plot of typical CMRR of the probe versus
input frequency. For additional information about CMRR, see
page 20.
The common-mode rejection of the probe is highest when the probe
is applied directly to the circuit, without using adapters. However,
some probing tasks are made easier using accessories incl uded with
the probe. The accessories shown in Figures 3 and 4 achieve a high
CMRR by minimizing the distance between the probe head and the
signal source.
The probe tip accessories included with your probe help connect to
different types of components. While these accessories make
connections easier, be aware tha t the adapter you choose may a ffect
the signal you are measuring, depending on a variety of factors,
including signal frequency, source impedance, and lead length.
Use the probe only (without adapters) to optimize step and frequency
response. Using the probe tip adapters adds inductance and
capacitance, which increases step response and aberrations, and leads
to increased ripples in frequency response. These effects increase as
the source impedance and the measured waveform risetimes
decrease.
The recommended method for hands-free probing is to use the probe
only (without adapters), with a probe positioner such as a Tektronix
PPM203B. If you need a tip space between 0.020 and 0.180 inches
apart, use the variable spacing adapter and the probe positioner. Use
the square pin adapter for test points or component leads spaced
farther than 0.180 inches apart.
Operating Basics
Figure 5 illustrates the typical effects on a given signal using some of
the adapters included with your probe.
Probe only
Variable
spacing
adapter
Square pin
adapter
Figure 5: Typical effects on a signal using probe tip adapters
When you connect the probe inputs to a circui t, you are introducing a
new resistance, capacitance, and inductance into the circuit. Each
input of the P6330 differential probe has a characteristic input
impedance of 50 kΩ to ground in parallel with le ss tha n 0.6 pF. See
Figure 6.
For signals with low source impedance and frequency, the 50 kΩ
input impedance on each input is large enough to prevent the inputs
from loading the signal sources. The greater the source impedances
and the higher the signal frequencies, the more you must take these
factors into account.
Input
+
0.6pF50kΩ
Ground
--
0.2 pF0.6 pF
Input
50 kΩ
Figure 6: Typical probe input model
As the impedance of the signal source on an input increases, the
more the probe loads the source and reduces the signal amplitude.
The frequency of the signal also affects signal measurement. As the
frequency of the signal increases, the input impedance of the probe
decreases. The lower the impedance of the probe relative to that of
the source, the more the probe loads the circuit under test and
reduces the signal amplitude. For a graph of frequency versus input
impedance, refer to Figure 12 on page 28.
In addition to the plus and minus inputs on the probe head, there is
also a ground (common) input. The ground lead slides into the notch
on the side of the probe. See Figure 7.
+
Operating Basics
-Ground
Figure 7: Probe ground input
CAUTION. To avoid damaging the circuitry under test, connect the
probe ground (common), if used, to a ground-reference point only.
In most applications, the common-mode impedance to ground is
greater than the differential impe dance. Adding the probe ground
lead does not improve the high-frequency performa nce of the
measurement. You can use the probe t o take a di fferential measurement regardless of whether or not the ground (common) is connected.
There are some applications that may require a ground reference
connection to maintain measurement accuracy. Generally this is
necessary when probing circuits which are fully isolated from
ground, such as battery operated devices.
After installing the probe on the oscilloscope, a functional check
may be performed using the PROBE COMPENSATION connections
on the front panel of the oscilloscope. See Figure 8.
Figure 8: Probe functional check connections
1. Connect the probe to the oscilloscope.
2. Set the oscilloscope to display the probe channel.
3. Connect the square pin adapter to the probe tip, and connect the
Y-lead adapter to the square pin adapter. Plug the SMT KlipChips
into the Y-lead adapter.
4. Connect the SMT KlipChips to the PROBE COMPENSATION
connections on the oscilloscope.
5. Adjust the oscilloscope to display a stable calibration waveform.
This section contains important referenc e information about
differential measurements and how to increase the accuracy of your
measurements.
Problems with Single-Ended Measurements
While suitable in many applications, single-ended measurements can
present problems in the following situations:
HWhen the signal is not referenced to eart h ground
HWhen the signal being measured is distorted or changed by
connecting or disconnecting the probe ground reference lead
Differential Measurements
Devices designed to make differential mea surements avoid the
problems posed by single-ended systems. These devices include a
variety of differential probes, differential amplifiers, and isolators.
The differential amplifier (Figure 9) is at the heart of any device or
system designed to make differential measurements. Ideally, the
differential amplifier rejects any voltage that is common to the inputs
and amplifies any difference between the inputs. Voltage that is
common to both inputs is often referred to as the Comm on-Mode
Voltage (V
Voltage (V
) and voltage that is different as the Differential-Mode
Figure 9: Simplified model of a differential amplifier
V
out
Common-Mode Rejection Ratio
In reality, differential amplifiers cannot reject all of the commonmode signal. The ability of a differential amplifier to reject the
common-mode signal is expressed as the Common-Mode Rejection
Ratio (CMRR). The CMRR is the differential-mode gain (A
divided by the common-mode gain (A
). It is expressed either as a
CM
DM
)
ratio or in dB.
A
DM
A
CM
CMRR =
A
DM
dB = 20 log
A
CM
CMRR generally is highest (best) at DC and degrades with
increasing frequency.
Assessing CMRR Error
Figure 11 on page 28 shows the CMRR of the P6330 differential
probe. This derating chart assumes a common-mode signal that is
sinusoidal.
A quick way to assess the magnitude of CMRR error when the
common-mode signal is not sinusoidal is to connect both leads to the
same point in the circuit. The oscilloscope will display only the
common-mode component which is not fully rejected by the probe.
While this technique may not give you entirely accurate measurements, it does allow you to determine if the magnitude of the
common-mode error signal is significant.
Input Impedance Effects on CMRR
The lower the input impedance of the probe relative to the source
impedance,thelowertheCMRR.SeeFigure12onpage28.
Significant differences in the source impedance driving the two
inputs will also lower the CMRR.
Extending the Input Leads
At times it may be necessary to extend the probe inputs with wires or
a probe tip adapter. When you do this, you should minimize the lead
lengths to optimize common-mode rejection and twist the input leads
together as shown in Figure 10.
Twisting the input leads together does increase capacitance that may
degrade high-frequency performance. You should take into account
any effects caused by the extended leads when you take a measurement.
Extending the ground lead will have little, if any, affect on your
measurements. In most circuits, the ground path from the differential
source has sufficiently high impedance to damp out any ringing
caused by lead inductance.
Extending the Probe Output
With the 1103 TEKPROBE power supply, it is possible to extend the
output of the probe to connect the probe to other types of measurement instruments or to connect the probe to a signal source that is
outside the reach of the probe.
Terminating the Probe
The probe must terminate into 50 Ω at the input of the measurement
instrument. Use the 1103 TEKPROBE power supply to adapt the
differential probe and set the input impedance of the measurement
instrument to 50 Ω. If the measurement instrument does not support
50 Ω input termination, connect a 50 Ω coaxial terminator on the
input.
As the frequency of a signal increases, current flow concentrates at
the outer edges of the conductor, effectively increasing the
impedance. This effect is known as skin loss. The P6330 probe
contains circuitry to compensate for skin loss.
The compensation provides flat response with the probe cable.
Extending the length of the output cable increases the amount of skin
loss beyond the range of compensation correction. Minimizing the
length of cable extension reduces the attenuation.
In critical applications which require high amplitude accuracy, you
should first characterize the response of the probe with the extension
using a leveled sinewave generator and power meter. Then, you can
factor the characterization results into the measurement.
Using the Probe with Other Instruments
You can use the P6330 differential probe with other types of
measurement instruments, such as spectrum analyzers, time internal
analyzers, and network analyzers.
When using the differential probes with these instruments, you must
use the 1103 TEKPROBE power supply, and normalize the probe
with the instrument before making a measurement.
The specifications in Tables 3 through 6 apply to a P6330 probe
installed on a TDS8000 oscilloscope. When the probe is used with
another oscilloscope, the oscilloscope must have an input impedance
of 50 Ω. The probe must have a warm-up period of at least
20 minutes and be in an environment that does not exceed the limits
described in Table 3. Specifications for the P6330 differential probe
fall into three categories: warranted, typical, and nominal characteristics.
Warranted Characteristics
Warranted characteristics (Table 3) describe guaranteed performance
within tolerance limits or certain type-tested requirements.
Warranted characteristics that have checks in the PerformanceVerification section are marked with the n symbol.
Table 3: Warranted electrical characteristics
Characteristic
n DC gain
n Output offset voltage± 10 mV (+ 20_ Cto+30_ C,
n Rise time (probe only)
Maximum nondestructive input voltage± 15 V(DC + peak AC) between signal and
Delay variation (probe-to-probe)600 ps maximum
Temperature
Description
0.2 ± 2%
+68_ Fto+86_ F)
± 50 mV displayed on screen with
TEKPROBE interface
Nonoperating: 0--90% RH, tested at
+30to+60_ C (+ 68 to + 140_ F)
WARNING. To avoid a burn hazard at high ambient temperatures, do
not touch the probe with bare hands at nonoperating temperatures
above + 70_ C. Allow sufficient time for the probe to cool before
handling
.
T ypical Characteristics
Typical characteristics (Tables 4 and 5) describe typical but not
guaranteed performance.
Figure 11 shows the typical common-mode gain of the probe. The
CMRR can be approximated by subtracting the common-mode gain
from the --14 dB reference level. For example, --80 dB CM gain
equals +66 dB CMRR.
Gain dB
-- 4 4
-- 5 2
-- 6 0
-- 6 8
-- 7 6
-- 8 4
10 MHz1 MHz100 MHz
Frequency
1GHz
Figure 11: Typical common-mode gain
The graph in Figure 12 represents simulation results of a first order
model of the probe input.
Impedance (Ω)
100 k
10 k
1k
100
28
10
1M
10 M
100 M
Frequency (Hz)
1G
Figure 12: Typical differential input impedance vs frequency
The following servicing instructions are for use only by
qualified personnel. To avoid injury, do not perform any
servicing other than that stated in the operating instructions
unless you are qualified to do so. Refer to all safety
summaries before performing any service.
Theory of Operation
There are no user replaceable parts within the probe or the
compensation box; however, this theory of operation is provided to
assist you in isolating failures to either the probe or the host
oscilloscope. Refer to Figure 14 for a simplified schematic of the
probe.
The probe head assembly contains an active amplifier circuit that
buffers and amplifies the input signal . The amp lifier receives power
and an offset level from the compensation box assembly via the
cable assembly.
All signal amplification and buffering is performed in the probe head
assembly. No further amplification takes place in the compensation
box.
Compensation Box
The compensation box contains the following circuits:
HOffset amplifier
HProbe identification EEPROM
HTEKPROBE interface
HDC CMRR adjustment circuitry
HV
Offset Amplifier
The offset amplifier is used to offset the DC component of the input
signal so that it stays at the optimal point of the linear dynamic range
of the probe.
The offset amplifier receives offset information as a ±1 VDC voltage
from the oscilloscope. The amplifier then amplifies it to match the
probe characteristics and applies it to the probe hybrid circuit.
The offset amplifier has two adjustments: offset zero and offset gain.
These adjustments rarely need attention; however, detailed
adjustment instructions are in the Adjustments sectiononpage47.
Probe Identification EEPROM
, +7 V linear regulator
CC
34
The probe identification EEPROM is used to configure the
oscilloscope to the probe. The EEPROM receives a c lock input from
the oscilloscope, and information about the probe is passed to the
oscilloscope.
The TEKPROBE interface provide s a communication path between
the probe and the oscilloscope. Contact pins provide power, signal,
offset, and data transfer for the probe identification EEPROM.
Figure 15 shows the TEKPROBE interface pin functions. Refer to
the service documenation for your oscilloscope for more detailed
specifications.
Use the following procedures to verify specifications of the P6330
probe. Before beginning these procedures, refer to page 46 and
photocopy the test record, and use it to record t he performanc e test
results. The recommended calibrat ion interval is one year.
These procedures test the following specifications:
HOutput offset voltage
HDC gain accuracy
HRise time
Equipment Required
Refer to Table 7 for a list of the equipment required to verify the
performance of your probe.
Table 7: Equipment required for performance verification
Item descriptionPerformance requirementRecommended example
High Speed Sampling
Oscilloscope
Probe Calibration FixtureSee page 39067-0419-00
Probe PositionerTektronix PPM203B
Power SupplyTEKPROBE interfaceTektronix 1103
Power Supply5.0 VDC at 1 mATektronix PS280
DMM (2), with leads0.1 mV resolutionFluke 87 or equivalent
Some of the procedures in this manual use a probe calibration
fixture, Tektronix part number 067-0419-00.
The calibration fixture provides a me ans to test the probe for both
common mode and differential mode measurements. SMA
connectors allow stimulus signals to connect to the fixt ure and are
located on the front and back of the fixture . The fixt ure is designed
to be used with a probe positioner, such as a Tektronix PPM203B.
Performance Verification
Figure 16: Probe Calibration Fixture
Using the Probe Calibration Fixture
1. Connect the fixture to the test circuit using an SMA cable.
2. Connect the 50 Ω terminator included with the fixture to the
unused SMA connector.
3. Insert and secure the probe in a probe positioner.
4. Position the probe over the fixture, using either the positioner
coarse adjustment or otherwise manipulating the positioner arm
in place.
5. Using the fine position and/or pressure adjust, maneuver the
probe so that the pins contact the CM or DM test points,
depending on which test you are performing. (See Figure 17.)
Common modeDifferential mode
Figure 17: Probe Calibration Fixture test points
6. Verify that contact is made on both pins. (You may need to
readjust the fine position and/or pressure adjustment to make
positive contact with the test points.)
This procedure verifies that the probe meets rise time specifications.
Two rise times are measured; the test system, and the test system
with the probe included. The probe rise time is calculated using the
two measurements.
1. Connect the test equipment as shown in Figure 20.
Performance Verification
SD24/ 80E04
Oscilloscope
CH1
CH2
BNC-to-SMA adapter
SMA cable 015-0562-00
SMA cable 174-1427-00
Figure 20: Test system rise time setup
2. Adjust the oscilloscope vertical sensitivity to 50 mV/div.
3. Turn on the TDR pulse on the SD-24 or TDS8000 (Ch 2).
4. Adjust the oscilloscope vertical positioning to center the signal on
screen.
015-0572-00
BNC-to-SMA adapter
015-0572-00
CH 1
output
CH 1
input
1103
5. Adjust the oscilloscope horizontal sensitivity to 500 ps/div.
6. Adjust the oscilloscope horizontal positioning to place the rising
edge of the signal where it crosses the second vertical and center
horizontal graticule lines.
7. Use the oscilloscope measurement capability to display rise time.
Rise time is determined from the 10% and 90% amplitude points
on the waveform. Record the rise time as t
If the measurement reading is not stable, use Average mode
(16 Averages) to improve stability.
The system rise time (t
rise time of the test system without the probe. The system rise time is
used to calculate the probe rise time (t
The following steps instruct you to assemble the test setup that
includes the probe, as shown in Figure 21. The system and probe rise
time (t
rise time (t
8. Disconnect the BNC-SMA adapter from the CH 1 input of the
1103 power supply and the SMA cable.
9. Connect the SMA cable to one input of the probe cal fixture, and
the terminator to the other input of the probe cal fixture.
10. Connect the probe to the 1103 power supply channel 1 input.
11. Turn off the offset control on channel 1 of the 1103 power supply.
12. Using the probe positioner, probe the DM test points on the probe
calibration fixture. Compare your display to Figure 22 to verify
that you have a valid connection with both pins.
500 ps/div
20% Gain
difference
Both pins in contact
(--) pin not making contact
Figure 22: Verifying both probe pins are contacting the DM test points
13. Adjust the oscilloscope vertical scale to 10 mV/div, averaging on.
14. Adjust the oscilloscope horizontal positioning to place the rising
edge of the signal so that it crosses the second vertical and center
horizontal graticule lines.
15. Use the oscilloscope measurement capability to display rise time.
Rise time is determined from the 10% and 90% amplitude points
on the waveform. Record the rise time as t
s+p.
16. Calculate the probe rise time using the following formula:
Ꭹ
tp=t
2
(s+p)
− t
2
s
17. Record the calculated probe rise time on the test record.
The P6330 has 3 internal controls: offset zero, offset range, and
DC CMRR. These controls should only be adjusted after a probe
performance verification and functional chec k has been performed
on the oscilloscope, and only if a check fails to meet its specification.
To make adjustments to the probe, the compensation box cover must
be removed and the equipment allowed to warm up for 20 minutes.
Equipment Required
In addition to the equipment required to perform the performance
verification, the adjustment procedures require the equipment listed
in Table 8.
Table 8: Additional equipment required for adjustment
Figure 24 shows the location of the adjustments and test points inside
the compensation box. Refer to Figure 24 when performing the
adjustment procedures in this section.
Use the following procedures to adjust the offset zero and DC CMRR
characteristics of the probe. Due to the interaction of the two
adjustments, it may be necessary to repeat the procedure to optimize
the adjustments.
NOTE. If your oscilloscope has a probe calibration routine, clear the
probe calibration constants at this time.
If the offset zero is adjusted, perform a functional check of the offset
range before closing the compensation box.
1. Connect the probe tips together using the square pin, Y-lead, and
KlipChip adapters.
2. Connect the probe as shown in Figure 18 on page 41.
3. Set the Var/0v button on the 1103 power supply to 0v (light off).
The output offset voltage is displayed on the DMM.
4. Adjust Offset Zero for 0.00 V ±3mV,displayedontheDMM.
Record the actual value.
5. Connect the probe as shown in Figure 25 on page 51. Monitor the
source voltage with the DMM.
14. Reverify that the offset is 0 V, ±3.0 mV (repeat steps 1
through 3). If the offset voltage magnitude is greater than 3.0 mV,
or if the CMRR is less than 60 dB, disconnect the probe from the
test circuit. Repeat the procedure, beginning with step 1 on
page 50, to compensate for the adjustment interaction.
Use this procedure to adjust the offset range of the probe. The offset
zero of the probe must be measured before making any adjustment to
the offset range. The offset zero voltage that you measure in the ZeroOffset procedure (step 4 on page 50), is the target value that you
adjust the offset range to. The offset range of the probe is approximately --1.0 to +1.0 volts. Take care not to disturb the power supply
settings as you perform these procedures.
1. Connect the equipment as shown in Figure 26.
2. Power on the 1103 power supply and turn on the offset.
6. Adjust Offset Range for a DMM reading equal to the value set in
the Zero Offset procedure (step 4 on page 50), ±3mV.Referto
Figure 24 on page 49 for the location of the offset range
adjustment.
This completes the adjustments to the probe. Replace the compensation box cover and do a performance verification of the probe.
Replacing the Compensation Box Cover
To replace the cover, follow these steps:
1. Align the TEKPROBE interface and the tab notches with the tabs
on the cover. Refer to Figure 27.
2. Press the cover catches in so that the cover can be lowered.
3. Slide the tab into the notch.
4. Firmly press the pieces together until the cover catches snap into
This section details the maintenance and repair procedures for the
P6330 differential probe.
Replacing TEKPROBE Interface Pins
TEKPROBE interface pins can stic k and fail to make contact after
time. Periodically check to see that each of the interface pins move
freely and fully extends out of the interface. If any pin fails to move
freely and fully extend, it should be replaced.
To remove a TEKPROBE interface pin, firmly grasp the pointed tip
with pliers and pull the pin out of the connector. See Figure 28.
No tools are required to install a replacement pin. Insert a new pin
into the connector socket as far as possible using finger pressure. If
necessary, seat the pin into the connector by pressing the tip gently
but firmly against a hard surface, such as a wood block or table top.
Removing and Replacing the TEKPROBE Interface Collar
To remove the TEKPROBE interface collar, firmly grasp the
compensation box body with one hand and the TEKPROBE interface
collar with the other hand. Firmly pull the interface collar off.
To replace the collar, first note the pin configuration on the
compensation box and their holes in the interface collar. The group
of three pins fit through the smaller of the two holes in the inte rface
collar. See Figure 29.
Align the tab to the slot, and gently press the two pieces together.
See Figure 29.
Once installed, the TEKPROBE c ollar should rotate freely to lock
and unlock.
56
Tab
Slot
Figure 29: Replacing the TEKPROBE interface collar
To prevent damage to probe materials, avoid using chemicals that
contain benzine, benzene, toluene, xylene, acetone, or similar
solvents.
Do not immerse the probe or use abrasive cleaners.
Dirt may be removed with a soft cloth dampened with a mild
detergent and water solution, or isopropyl alcohol.
Replacement Parts
Refer to the Replaceable Parts section for a list of customer
replacement parts. Due to the sophisticated design of the P6330,
there are no user replaceable parts within the probe.
Maintenance
Preparation for Shipment
If the original packaging is unfit for use or not available, use the
following packaging guidelines:
1. Use a corrugated cardboard shipping carton having inside
dimensions at least one inch greater than the probe dimensions.
The box should have a carton test strength of at least 200 pounds.
2. Put the probe into an antistatic bag or wrap to protect it from
dampness.
3. Place the probe into the box and stabilize it with light packing
material.
This section contains a list of replaceable parts for the P6330
differential probe. Use this list to identify and order replacement
parts.
Parts Ordering Information
Replacement parts are available from or through your local
Tektronix, Inc. service center or representative.
Changes to Tektronix instruments are sometimes made to accommodate improved components as they become available and to give you
the benefit of the latest circuit improvements. Therefore, when
ordering parts, it is important to include the following information in
your order:
HPart number
HInstrument type or model number
HInstrument serial number
HInstrument modification number, if applicable
If a part you order has been replac ed with a different or improved
part, your local Tektronix service center or representative will
contact you concerning any change in the part number.
The tabular information in the Repl aceable Parts List is arranged for
quick retrieval. Understanding the structure and features of the list
will help you find the information you need for ordering replacement
parts.
Item Names
In the Replaceable Parts List, an Item Name is separated from the
description by a colon (:). Because of space limitations, an Item
Name may sometimes appear as incomplete. For further Item Name
identification, U.S. Federal Cataloging Handbook H6-1 can be used
where possible.
Indentation System
This parts list is indented to show the relationship between items.
The following example is of the indentation system used in the
Description column:
12345Name&Description
Assembly and/or Component
Attaching parts for Assembly and/or Component
(END ATTACHING PARTS)
Detail Part of Assembly and/or Component
Attaching parts for Detail Part
(END ATTACHING PARTS)
Parts of Detail Part
Attaching parts for Parts of Detail Part
(END ATTACHING PARTS)
Attaching parts always appear at the same indentation as the item it
mounts, while the detail parts are indented to the right. Indented
items are part of, and included with, the next higher indentation.
Attaching parts must be purchased separately, unless otherwise
specified.
Abbreviations
60
Abbreviations conform to American National Standards Institute
(ANSI) standard Y1.1