AVTECH ELECTROSYSTEMS LTD. AVRQ-4-B User manual

INSTRUCTIONS
MODEL AVRQ-4-B
KILOVOLT AMPLITUDE
ADJUSTABLE RISE TIME
PULSE GENERATORS FOR
COMMON MODE TRANSIENT IMMUNITY (CMTI) TESTS
SERIAL NUMBER: 1405
A V T E C H E L E C T R O S Y S T E M S L T D .
N A N O S E C O N D W A V E F O R M E L E C T R O N I C S
S I N C E 1 9 5
[e-mail]
http://www.avtechpulse.com/
Tel: [phone] (USA & Canada) or [phone] (Intl)
Fax: [phone] (USA & Canada) or [phone] (Intl)
BOX 5120, LCD MERIVALE
OTTAWA, CANADA K2C3H5

WARRANTY
Avtech Electrosystems Ltd. warrants products of its manufacture to be free
from defects in material and workmanship under conditions of normal use. If,
within one year after delivery to the original owner, and after prepaid return by
the original owner, this Avtech product is found to be defective, Avtech shall at
its option repair or replace said defective item. This warranty does not apply to
units which have been dissembled, modified or subjected to conditions
exceeding the applicable specifications or ratings. This warranty is the extent of
the obligation assumed by Avtech with respect to this product and no other
warranty or guarantee is either expressed or implied.
TECHNICAL SUPPORT
Phone: [phone] (USA & Canada) or [phone] (International)
Fax: [phone] (USA & Canada) or [phone] (International)
E-mail: [e-mail]
World Wide Web: http://www.avtechpulse.com
2

TABLE OF CONTENTS
WARRANTY......................................................................................................................2
TECHNICAL SUPPORT...................................................................................................2
TABLE OF CONTENTS....................................................................................................3
INTRODUCTION...............................................................................................................6
HIGH-VOLTAGE PRECAUTIONS....................................................................................8
SPECIFICATIONS............................................................................................................9
REGULATORY NOTES..................................................................................................10
FCC PART 18........................................................................................................................10
EC DECLARATION OF CONFORMITY................................................................................10
DIRECTIVE 2011/65/EU (RoHS)..........................................................................................11
DIRECTIVE 2002/96/EC ( EEE)..........................................................................................11
FIRM ARE LICENSING.......................................................................................................12
INSTALLATION..............................................................................................................13
VISUAL CHECK....................................................................................................................13
PO ER RATINGS................................................................................................................13
CONNECTION TO THE PO ER SUPPLY...........................................................................13
PROTECTION FROM ELECTRIC SHOCK...........................................................................14
ENVIRONMENTAL CONDITIONS........................................................................................15
FUSES.............................................................................................................................16
AC FUSE REPLACEMENT...................................................................................................16
DC FUSE REPLACEMENT...................................................................................................17
FUSE RATINGS....................................................................................................................17
CHASSIS CONFIGURATIONS.......................................................................................18
STANDARD CONFIGURATION............................................................................................18
-FPD CONFIGURATION.......................................................................................................18
FRONT PANEL CONTROLS (UNITS WITHOUT -FPD OPTION .................................19
REAR PANEL CONTROLS (UNITS WITHOUT -FPD OPTION ...................................21
FRONT PANEL CONTROLS (UNITS WITH -FPD OPTION ........................................24
REAR PANEL CONTROLS (UNITS WITH -FPD OPTION ...........................................28
GENERAL INFORMATION............................................................................................30
BASIC PULSE CONTROL....................................................................................................30
TRIGGER MODES................................................................................................................31
3

GATING MODES...................................................................................................................32
DUT INSTALLATION......................................................................................................33
SOCKET PINOUT.................................................................................................................33
STANDARD DAUGHTERBOARD PINOUT..........................................................................34
STANDARD DAUGHTERBOARD COMPONENTS..............................................................35
SO-8 DAUGHTERBOARD (PCB 314A)................................................................................37
CUSTOM DAUGHTERBOARDS...........................................................................................37
DIFFERENTIAL PROBING...................................................................................................38
INSTALLING THE DAUGHTERBOARDS.............................................................................38
CUSTOMER-SPECIFIC - DIP16A DAUGHTERBOARD....................................................39
BASIC TEST ARRANGEMENTS...................................................................................42
INTER-CHANNEL INTERFERENCE.....................................................................................43
TYPICAL WAVEFORMS FOR STANDARD DAUGHTERBOARDS.............................45
BASIC THEORY.................................................................................................................... 45
TYPICAL POSITIVE RESULTS, ITH NO DUT INSTALLED.............................................47
TYPICAL NEGATIVE RESULTS, ITH NO DUT INSTALLED............................................48
HCPL-7721 RESULTS..........................................................................................................49
INDUCTIVE SPIKES AND PROBE SATURATION.......................................................52
DC CORRECTNESS ISSUES.........................................................................................52
VERIFICATION AND TROUBLESHOOTING................................................................53
SAFETY CONCERNS.....................................................................................................55
TURN OUTPUT OFF BEFORE ACCESSING DUT...............................................................55
AUTOMATIC TIMEOUT........................................................................................................55
OVERLOAD INDICATOR......................................................................................................55
OPERATIONAL CHECK.................................................................................................56
PROTECTING YOUR INSTRUMENT.............................................................................59
USE HIGH-VOLTAGE CABLES, CONNECTORS, AND PROBES......................................59
SHORT-CIRCUIT PROTECTION..........................................................................................59
MECHANICAL INFORMATION......................................................................................60
TOP COVER REMOVAL.......................................................................................................60
RACK MOUNTING................................................................................................................60
MAINTENANCE..............................................................................................................61
REGULAR MAINTENANCE..................................................................................................61
CLEANING............................................................................................................................ 61
4

TRIGGER DAMAGE..............................................................................................................61
PROGRAMMING YOUR PULSE GENERATOR............................................................62
KEY PROGRAMMING COMMANDS....................................................................................62
ALL PROGRAMMING COMMANDS.....................................................................................63
WIRING DIAGRAMS.......................................................................................................65
IRING OF AC PO ER.......................................................................................................65
IRING OF +54VDC PO ER RAIL (FOR -SCHB OPTION)...............................................66
PCB 158R5 - LO VOLTAGE PO ER SUPPLY................................................................67
PCB 104G - KEYPAD / DISPLAY BOARD...........................................................................68
PCB 228C - OP AMPS (-AHV AND -XHV UNITS)................................................................69
DUT IRING, ON MAIN PCB...............................................................................................70
DUT IRING, ON STANDARD DAUGHTERBOARD (PCB 267D)......................................71
DUT IRING, ON SO-8 DAUGHTERBOARD (PCB 314A)..................................................72
DUT IRING, ON DIP16 DAUGHTERBOARD (PCB 325A).............................................73
MAIN IRING.......................................................................................................................74
PERFORMANCE CHECK SHEET.................................................................................75
Manual Reference: /fileserver2/officefiles/instructword/avrq/AVRQ-4-B,ed14.odt.
Last modified December 21, 2020.
Copyright © 2020 Avtech Electrosystems Ltd, All Rights Reserved.
5

INTRODUCTION
The AVRQ-4-B is designed to test the common mode transient immunity (CMTI) of
optocouplers.
The standard AVRQ-4-B can generate -1.5, -1.0, +1.0, or +1.5 kV pulses. The switching
time (10%-90%) is adjustable from 20 ns up to 500 ns, using the front panel menus or
computer commands. At 1.5 kV, this corresponds to transition rates of 2.4 to 60 kV/us.
The -AHV option provides greater flexibility in the amplitude setting, permitting
adjustment from 1.0 to 1.5 kV (+ or -) in ≤ 1V steps.
The -XHV option provides a different amplitude range of 1.5 to 2.0 kV (+ or -) in ≤ 1V
steps, but the minimum switching time increases to 25 ns.
A daughterboard arrangement is used to accommodate difference device packages
and bias conditions. An arrangement of pin sockets on the main motherboard accepts
these daughterboards. Eight daughterboards suitable for use with typical 5V DIP8
packages are included with the AVRQ-4-B. The CAD/CAM files for these sample
boards are available for download at:
https://www.avtechpulse.com/semiconductor/avrq-4/#support_files
Users may design their own daughterboards to accommodate other package styles.
(Earlier AVRQ-4-B units, prior to S/N 13 00, used a different socketing and
daughterboard arrangement. Current units have a different arrangement that offers
lower parasitic inductance.)
The AVRQ-4-B mainframe provides the high-voltage common mode pulse (which is tied
to GND1), and VCC2 / GND2 (the non-floating output-side power supply). The user is
responsible for configuring the daughterboards to implement the correct input side
power (VCC1), biasing, filtering, loading, socketing, and glitch measurement. The
included sample boards implement these requirements for common DIP8 devices,
using configurable jumpers/resistors/capacitors. A probe point is provided on the
motherboard for observation of the device logic output with a user-provided probe and
oscilloscope. An optional probe point is also provided on the sample daughterboards.
The ground-referenced output-side power (VCC2) is generated by the mainframe, and
is adjustable (+3V to +8V, or to +43V with the -SCHB option, 150 mA maximum). The
floating input-side power is not provided by the mainframe. Instead, an A23-type 12V
battery should be installed on the DUT daughterboard to provide a floating power
source, along with a basic regulator circuit to provide the necessary regulated +5V
power (VCC1). A isolated battery arrangement is used to ensure that the VCC1 power
supply is not the source of any glitches observed in the operation of the DUT.
6

The high-voltage pulse and the logic output of the DUT must be measured by the user,
using suitable high-impedance oscilloscope probes. Coaxial cabling should not be
used, because it will introduce too much parasitic capacitance.
The AVRQ-4-B features front panel keyboard and adjust knob control of the output
pulse parameters along with a four line by 40-character backlit LCD display of the rise
time, pulse width, pulse delay, and pulse repetition frequency. The instrument includes
memory to store up to four complete instrument setups. The operator may use the front
panel or the computer interface to store a complete “snapshot” of all key instrument
settings, and recall this setup at a later time.
This instrument is intended for use in research, development, test and calibration
laboratories by qualified personnel.

HIGH-VOLTAGE PRECAUTIONS
CAUTION: This instrument provides output voltages as high as 1500 or 2000 Volts
under normal operating conditions, so extreme caution must be employed when using
this instrument. The instrument should only be used by individuals who are thoroughly
skilled in high voltage laboratory techniques. The following precautions should always
be observed:
1. Keep exposed high-voltage wiring to an absolute minimum.
2. Wherever possible, use shielded connectors and cabling.
3. Connect and disconnect loads and cables only when the instrument is turned off.
4. Keep in mind that all cables, connectors, oscilloscope probes, and loads must
have an appropriate voltage rating.
Do not attempt any repairs on the instrument, beyond the fuse replacement procedures
described in this manual. Contact Avtech technical support (see page 2 for contact
information) if the instrument requires servicing.
8

SPECIFICATIONS
Model: AVRQ-4-B1
High-Voltage Pulse Amplitude:
(HV pulse / GND1)
Standard: -1.5, -1, +1, or +1.5 kV
with -AHV9 option: -1 kV to -1.5 kV,
+1 kV to +1.5 kV, in ≤ 1V steps
with -XHV10 option: -1.5 kV to -2 kV,
-1.5 kV to -2 kV, in ≤ 1V steps
Load resistance: > 10 Megohms (this is not a 50 Ohm system.)
Load capacitance (CLOAD): < 15 pF total, including DUT capacitance and probes
(can tolerate up to 300 pF, but the switching times will degrade significantly).
Load connection style: A pattern of pin sockets into which a daughterboard may be plugged is provided. Sample daughterboards
with 8-pin DIP sockets are included. The user may also user their own custom-made daughterboards.
Leading edge rise time for maximum
output voltage2 (10% - 90%):
< 20 ns12 (< 25 ns with -XHV option10,12) up to > 500 ns,
adjustable using front-panel settings or computer command.
Leading edge shape: Approximately linear. See the typical waveform photos on the preceding and following pages.
Trailing edge fall time3 (90%-10%): At least ten times greater than the leading edge rise time. Not adjustable.
Trailing edge shape: Exponential decay, approximately. See the typical waveform photos on the preceding and following pages.
Pulse width (measured between the start
of the leading edge and the start of the
falling edge):
1 - 20 us, adjustable.
PRF: Standard: 10 Hz maximum
-HF option: 100 Hz maximum
VCC1 power supply (input side, floating,
referenced to HV pulse / GND1):
Not provided by the mainframe. The input side of the daughterboards must be self-powered.
The included sample boards use an A23-type battery with a low-dropout regulator.
VCC2 power supply11 (output side,
referenced to GND2 chassis ground):
Standard: +3 to +8V, adjustable, 150 mA maximum
Optional : +3 to +43V, adjustable, 150 mA maximum
Logic output pull-up resistance: User-installed, on daughterboard as appropriate
Output connector, HV PULSE: BNC female, suitable for use with the Tektronix P5100 high-voltage probe and 013-0291-00 probe-tip-to-
BNC adapter. Other probes may be suitable. Not intended to drive any length of coaxial cabling directly.
Output connector, logic output: A two-pin header suitable for use with the Tektronix P6246 differential probe8.
Other probes may be used by installing a matching two-pin socket as an extender.
Output enable timer: The output will only remain active for 90 seconds after the last output parameter update.
After that time, the output will be disabled. The output must be re-enabled
from the front panel or by computer command for the next test sequence.
Propagation delay: ≤ 200 ns (Ext trig in to start of output pulse)
Jitter (Ext trig in to pulse out): ± 200 ps ± 0.03% of sync delay
Trigger modes: Internal trigger, external trigger (TTL level pulse, > 10 ns, 1 kΩ input impedance),
front-panel “Single Pulse” pushbutton, or single pulse trigger via computer command.
Variable delay: Sync to Out: 0 to ±1.0 seconds, for all trigger modes (including external trigger).
Sync output: +3 Volts, 100 ns, will drive 50 Ohm loads
Gate input: Synchronous, active high or low, switchable. Suppresses triggering when active.
Other connectors: Trig, Sync, Gate: BNC
GPIB and RS-232 control: Yes. (Visit http://www.avtechpulse.com/labview for LabView drivers.)
Ethernet port, for remote control using
VXI-11.3, ssh, telnet, & web:
Optional4. Recommended as a modern alternative to GPIB / RS-232.
See http://www.avtechpulse.com/options/vxi for details.
Settings accuracy: Not calibrated. Verify the output parameters with a calibrated oscilloscope.
Power requirements: 100 - 240 Volts, 50 - 60 Hz
Dimensions: (H x W x D) 145 x 430 x 4 5 mm (5. ” x 1 ” x 18.8”)
Chassis material: cast aluminum frame and handles, blue vinyl on aluminum cover plates
Temperature range: +5°C to +40°C
1) -B suffix indicates IEEE-488.2 GPIB and RS-232 control of amplitude, pulse width, PRF and delay (See http://www.avtechpulse.com/gpib/).
2) The rise time is affected by the load capacitance. A high-voltage high-bandwidth oscilloscope probe such as the Tektronix P5100 should always be used to verify the
actual output rise time, rather than relying on the programmed value.
3) Refers to the trailing edge, which swings from -1000V or -2000V to 0V
4) Add the suffix -VXI to the model number to specify the Ethernet port.
5) Note that coaxial cabling typically adds 30 pF/ft.
6) The user must install a standard 9V battery in the provided holder, in order to power the floating power supply. The battery is not included, due to shipping regulations.
) To specify the extended VCC2 range, add the -SCHB option suffix to the model number.
8) A differential probe is suggested to reduce the possibility of interference from the high-voltage pulse. Note that the P6246 is only suitable for values of VCC2 up to + V.
A non-differential probe may be more suitable if VCC2 > V, or if parasitic inductances or capacitances in the test circuit cause differential voltage spikes exceeding
± V. The P6246 can saturate under those conditions, which can generate apparent glitch-like transients that are not due to the DUT. Some experimentation may be
required by the user in order to identify the best probing arrangement.
9) Add the suffix -AHV to the model number to specify the +/- 1 to 1.5 kV (in ≤ 1V steps) operating range.
10) Add the suffix -XHV to the model number to specify the +/- 1.5 to 2 kV (in ≤ 1V steps) operating range. This optiion increases the minimum switching time by 5 ns.
11) VCC2 is normally provided at the DUT socket. It can also be provided on a BNC connector for monitoring purposes by specifying the -V2 option. The BNC connnector
will be on the same panel as the DUT enclosure (rear panel for standard units, front panel for -FPD units.) The shield of this BNC connector is connected to GND2 /
chassis ground.
12) Valid with a Tektronix P5100 high-voltage probe connected directly to the HV PULSE connector. Connecting anything else (e.g., additional coaxial cabling or external
DUTs) may degrade the switching times significantly.
9

REGULATORY NOTES
FCC PART 18
This device complies with part 18 of the FCC rules for non-consumer industrial,
scientific and medical (ISM) equipment.
This instrument is enclosed in a rugged metal chassis and uses a filtered power entry
module (where applicable). The main output signal is provided on a shielded connector
that is intended to be used with shielded coaxial cabling and a shielded load. Under
these conditions, the interference potential of this instrument is low.
If interference is observed, check that appropriate well-shielded cabling is used on the
output connectors. Contact Avtech ([e-mail]) for advice if you are unsure
of the most appropriate cabling. Also, check that your load is adequately shielded. It
may be necessary to enclose the load in a metal enclosure.
If any of the connectors on the instrument are unused, they should be covered with
shielded metal “dust caps” to reduce the interference potential.
This instrument does not normally require regular maintenance to minimize interference
potential. However, if loose hardware or connectors are noted, they should be
tightened. Contact Avtech ([e-mail]) if you require assistance.
EC DECLARATION OF CONFORMITY
We Avtech Electrosystems Ltd.
P.O. Box 5120, LCD Merivale
Ottawa, Ontario
Canada K2C 3H5
declare that this pulse generator meets the intent of Directive 2004/108/EG for
Electromagnetic Compatibility. Compliance pertains to the following specifications as
listed in the official Journal of the European Communities:
EN 50081-1 Emission
EN 50082-1 Immunity
10

and that this pulse generator meets the intent of the Low Voltage Directive 2006/95/EC.
Compliance pertains to the following specifications as listed in the official Journal of the
European Communities:
EN 61010-1:2001 Safety requirements for electrical equipment for
measurement, control, and laboratory use
DIRECTIVE 2011/65/EU (RoHS)
We Avtech Electrosystems Ltd.
P.O. Box 5120, LCD Merivale
Ottawa, Ontario
Canada K2C 3H5
declare that, to the best of our knowledge, all electrical and electronic equipment (EEE)
sold by the company are in compliance with Directive 2011/65/EU of the European
Parliament and of the Council of 8 June 2011 on the restriction of the use of certain
hazardous substances in electrical and electronic equipment (also known as “RoHS
Recast”). In addition, this declaration of conformity is issued under the sole
responsibility of Avtech Electrosystems Ltd. Specifically, products manufactured do not
contain the substances listed in the table below in concentrations greater than the listed
maximum value.
Material/Substance Threshold level
Lead (Pb) < 1000 ppm (0.1% by mass)
Mercury (Hg) < 1000 ppm (0.1% by mass)
Hexavalent Chromium (Cr6+) < 1000 ppm (0.1% by mass)
Polybrominated Biphenyls (PBB) < 1000 ppm (0.1% by mass)
Polybrominated Diphenyl ethers (PBDE) < 1000 ppm (0.1% by mass)
Cadmium (Cd) < 100 ppm (0.01% by mass)
Bis(2-ethylhexyl) phthalate (DEHP) < 1000 ppm (0.1% by mass)
Butyl benzyl phthalate (BBP) < 1000 ppm (0.1% by mass)
Dibutyl phthalate (DBP) < 1000 ppm (0.1% by mass)
Diisobutyl phthalate (DIBP) < 1000 ppm (0.1% by mass)
DIRECTIVE 2002/96/EC (WEEE)
European customers who have purchased this equipment directly from Avtech will have
completed a “WEEE Responsibility Agreement” form, accepting responsibility for WEEE
compliance (as mandated in Directive 2002/96/EC of the European Union and local
11

laws) on behalf of the customer, as provided for under Article 9 of Directive
2002/96/EC.
Customers who have purchased Avtech equipment through local representatives
should consult with the representative to determine who has responsibility for WEEE
compliance. Normally, such responsibilities with lie with the representative, unless other
arrangements (under Article 9) have been made.
Requirements for WEEE compliance may include registration of products with local
governments, reporting of recycling activities to local governments, and financing of
recycling activities.
FIRMWARE LICENSING
Instruments with firmware versions 5.00 or higher use open-source software internally.
Some of this software requires that the source code be made available to the user as a
condition of its licensing. This source code is available upon request (contact
[email protected]om).
Earlier firmware versions do not contain any open source software.
12

INSTALLATION
VISUAL CHECK
After unpacking the instrument, examine to ensure that it has not been damaged in
shipment. Visually inspect all connectors, knobs, liquid crystal displays (LCDs), and the
handles. Confirm that a power cord, a GPIB cable, and two instrumentation manuals
(this manual and the “Programming Manual for -B Instruments”) are with the
instrument. If the instrument has been damaged, file a claim immediately with the
company that transported the instrument.
The following additional items should be with the instrument (for standard models):
1. Eight assembled PCB 26 D daughterboards
2. Eight A23-type 12V batteries
Additional items may be included, depending on the options ordered.
POWER RATINGS
This instrument is intended to operate from 100 - 240 V, 50 - 60 Hz.
The maximum power consumption is 5 Watts. Please see the “FUSES” section for
information about the appropriate AC and DC fuses.
This instrument is an “Installation Category II” instrument, intended for operation from a
normal single-phase supply.
CONNECTION TO THE POWER SUPPLY
An IEC-320 three-pronged recessed male socket is provided on the back panel for AC
power connection to the instrument. One end of the detachable power cord that is
supplied with the instrument plugs into this socket. The other end of the detachable
power cord plugs into the local mains supply. Use only the cable supplied with the
instrument. The mains supply must be earthed, and the cord used to connect the
instrument to the mains supply must provide an earth connection. (The supplied cord
does this.)
Warning: Failure to use a grounded outlet may result in injury or death due to
electric shock. This product uses a power cord with a ground connection. It must be
connected to a properly grounded outlet. The instrument chassis is connected to the
ground wire in the power cord.
The table below describes the power cord that is normally supplied with this instrument,
depending on the destination region:
13

Destination Region Description Option Manufacturer Part Number
United Kingdom, Hong Kong,
Singapore, Malaysia
BS 1363,
230V, 50 Hz -AC00 Qualtek 3 0001-E01
Australia, New Zealand AS 3112:2000,
230-240V, 50 Hz -AC01 Qualtek 3 4003-A01
Continental Europe, Korea,
Indonesia, Russia
European CEE /
“Schuko” 230V, 50 Hz -AC02 Qualtek 364002-D01
North America, Taiwan NEMA 5-15,
120V, 60 Hz -AC03 Qualtek 31200 -01
Switzerland SEV 1011,
230V, 50 Hz -AC06 Qualtek 3 8001-E01
South Africa, India SABS 164-1,
220-250V, 50 Hz -AC1 Volex 2131H 10 C3
Japan JIS 8303,
100V, 50-60 Hz -AC18 Qualtek 39 002-01
Israel SI 32,
220V, 50 Hz -AC19 Qualtek 398001-01
China GB 1002-1 / 2099-1,
220V, 50 Hz -AC22 Qualtek 399012-01
PROTECTION FROM ELECTRIC SHOCK
Operators of this instrument must be protected from electric shock at all times. The
owner must ensure that operators are prevented access and/or are insulated from
every connection point. In some cases, connections must be exposed to potential
human contact. Operators must be trained to protect themselves from the risk of
electric shock. This instrument is intended for use by qualified personnel who recognize
shock hazards and are familiar with safety precautions required to avoid possibly injury.
In particular, operators should:
1. Keep exposed high-voltage wiring to an absolute minimum.
2. Wherever possible, use shielded connectors and cabling.
3. Connect and disconnect loads and cables only when the instrument is turned off.
4. Keep in mind that all cables, connectors, oscilloscope probes, and loads must
have an appropriate voltage rating.
5. Do not attempt any repairs on the instrument, beyond the fuse replacement
procedures described in this manual. Contact Avtech technical support (see
page 2 for contact information) if the instrument requires servicing. Service is to
be performed solely by qualified service personnel.
14

ENVIRONMENTAL CONDITIONS
This instrument is intended for use under the following conditions:
1. indoor use;
2. altitude up to 2 000 m;
3. temperature 5 °C to 40 °C;
4. maximum relative humidity 80 % for temperatures up to 31 °C decreasing
linearly to 50 % relative humidity at 40 °C;
5. Mains supply voltage fluctuations up to ±10 % of the nominal voltage;
6. no pollution or only dry, non-conductive pollution.
15

FUSES
This instrument contains four fuses. All are accessible from the rear-panel. Two protect
the AC prime power input, and two protect the internal DC power supplies. The
locations of the fuses on the rear panel are shown in the figure below:
AC FUSE REPLACEMENT
To physically access the AC fuses, the power cord must be detached from the rear
panel of the instrument. The fuse drawer may then be extracted using a small flat-head
screwdriver, as shown below:
16
Fuses #1 and #2
(AC fuses)
Fuse #4
(DC fuse)
Fuse #
(DC fuse)
Fuse
Drawer
Pry out the fuse
drawer using a
screwdriver.

DC FUSE REPLACEMENT
The DC fuses may be replaced by inserting the tip of a flat-head screwdriver into the
fuse holder slot, and rotating the slot counter-clockwise. The fuse and its carrier will
then pop out.
FUSE RATINGS
The following table lists the required fuses:
Fuses
Nominal
Mains
Voltage
Rating Case Size
Recommended Replacement Part
Littelfuse Part
Number
Digi-Key Stock
Number
#1, #2 (AC) 100-240V 0.5A, 250V,
Time-Delay 5×20 mm 0218.500HXP F2416-ND
#3 (DC) N/A 1.6A, 250V,
Time-Delay 5×20 mm 021801.6HXP F2424-ND
#4 (DC) N/A 0.5A, 250V,
Time-Delay 5×20 mm 0218.500HXP F2416-ND
The recommended fuse manufacturer is Littelfuse (http://www.littelfuse.com).
Replacement fuses may be easily obtained from Digi-Key (http://www.digikey.com) and
other distributors.
1

CHASSIS CONFIGURATIONS
The AVRQ-4-B is offered with two basic chassis configurations. The standard model is
provided in a “3U” height (in rack units) enclosure, with the DUT area located on the
rear panel.
The DUT area may optionally be moved to the front panel by specifying the -FPD
option. This is more convenient for the user, but it increases the height of the
instrument from 3U to 5U, and higher shipping costs may apply.
STANDARD CONFIGURATION
Front Rear
-FPD CONFIGURATION
Front Rear
18

FRONT PANEL CONTROLS (UNITS WITHOUT -FPD OPTION)
1. POWER Switch . This is the main power switch. When turning the instrument on,
there is normally a delay of 10 seconds before anything is shown on the main display,
as the internal operating system boots up.
If the main menu does not appear after 30 seconds, turn off the instrument and leave it
off for at least 60 seconds before applying power again.
2. OVERLOAD Indicator . When the instrument is powered, this indicator is normally
green, indicating normal operation. If this indicator is yellow, an internal automatic
overload protection circuit has been tripped. If the unit is overloaded (by operating at an
exceedingly high duty cycle or by operating into a very low impedance), the protective
circuit will disable the output of the instrument and turn the indicator light yellow. The
light will stay yellow (i.e. output disabled) for about 5 seconds after which the instrument
will attempt to re-enable the output (i.e. light green) for about 1 second. If the overload
condition persists, the output will be disabled again (i.e. light yellow) for another 5
seconds. If the overload condition has been removed, the instrument will resume
normal operation.
This overload indicator may flash yellow briefly at start-up. This is not a cause for
concern.
3. SYNC OUT . This connector supplies a SYNC output that can be used to trigger
other equipment, particularly oscilloscopes. This signal leads (or lags) the main output
by a duration set by the "DELAY" controls and has an approximate amplitude of +3
Volts to RL > 1 kΩ with a pulse width of approximately 100 ns.
4. LIQUID CRYSTAL DISPLAY (LCD) . This LCD is used in conjunction with the
keypad to change the instrument settings. Normally, the main menu is displayed, which
19
1
53
24

lists the key adjustable parameters and their current values. The “Programming Manual
for -B Instruments” describes the menus and submenus in detail.
5. KEYPAD .
Control Name Function
MOVE This moves the arrow pointer on the display.
CHANGE This is used to enter the submenu, or to select the operating
mode, pointed to by the arrow pointer.
×10 If one of the adjustable numeric parameters is displayed, this
increases the setting by a factor of ten.
÷10 If one of the adjustable numeric parameters is displayed, this
decreases the setting by a factor of ten.
+/- If one of the adjustable numeric parameters is displayed, and
this parameter can be both positive or negative, this changes
the sign of the parameter.
EXTRA FINE This changes the step size of the ADJUST knob. In the extra-
fine mode, the step size is twenty times finer than in the normal
mode. This button switches between the two step sizes.
ADJUST This large knob adjusts the value of any displayed numeric
adjustable values, such as frequency, pulse width, etc. The
adjust step size is set by the "EXTRA FINE" button.
When the main menu is displayed, this knob can be used to
move the arrow pointer.
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