BNC 6040 User manual

Model 6040
Universal Pulse Generator
2955 Kerner Blvd. Ste D. San Rafael, CA 94901 Ph: 415-453-9955 Fx: 415-453-9956
www.berkeleynucleonics.com
Instruction Manual

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WARRANTY
Berkeley Nucleonics Corporation warrants all instruments, including
component parts, to be free from defects in material and
workmanship, under normal use and service for a period of one
year. If repairs are required during the warranty period, contact the
factory for component replacement or shipping instructions. Include
serial number of the instrument. This warranty is void if the unit is
repaired or altered by others than those authorized by Berkeley
Nucleonics Corporation.

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CONTENTS
Page
SECTION 1 SPECIFICATIONS 9
Model 6040 Mainframe Characteristics 9
Status Byte Summaries 13
SECTION 2 OPERATING INFORMATION 15
General 15
Power Up 15
LCD Power On Sequence 15
Module Installation 16
Warm Up Requirements 16
Safety Precautions 16
Electrical Cables, Attenuators and Oscilloscopes 16
Troubleshooting 17
LCD Contrast 17
Cold Boot 17
Quick Test 17
GPIB and RS-232 Problems 18
Front Panel Description 19
Power Switch 19
LCD Display 19
LED Annunciator 19
Keypads 19
Control Keypad 20
Numeric Keypad 20
Connectors 20
Plug-In Module Receptacle 21
Rear Panel Description 21
GPIB Connector 21
RS-232 Connector 21
ECL OUT Connector 21
MODULE DISABLE Jack 21
RESET Button 115 V/ 230 V Selection Switch and Fuse 22
Front Panel Programming 22
General 22

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CONTENTS
Menus and Parameter Selection 22
Modifying Parameters 23
Numeric Data Entry 24
Parameter Scanning 25
Saving the Panel Setting in Memory 25
Control Key Descriptions 26
Menu Keys 28
Memory Keys 31
Scan Keys 32
Function Keys 32
Miscellaneous Keys 32
Numeric Key Descriptions 33
Remote Programming 34
Initial Bus Parameter Selection 35
Command Set 35
Status Commands 35
Panel Control Commands 37
Display Commands 39
Supplemental Control Commands 40
SECTION 3 THEORY OF OPERATION 41
General 41
Pulse Generator 41
Software and Microprocessor 41
Circuit Description 42
Simplified Interconnection Diagram 42
Timing Board 42
Rep-Rate Generator and External Trigger Circuit 42
Delay Circuit 43
Width Circuit 43
Microprocessor Board 44
CPU and Interface 44
Memory and I/O Decoding 46
Timer and I/O Decoding 46
Front Panel Interface 47
ECL Interface 49
CMOS Delay Circuit 49
GPIB Interface 51
Module Interface 51
PLL and Rate Limiter 51
Power Supply Board 55

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CONTENTS
SECTION 4 MAINTENANCE AND CALIBRATION 56
Calibration 56
General 56
Equipment Required 56
Procedure 56
Power Supply 56
LCD Contrast 56
Rep-Rate Check 57
External Trigger Circuit 57
Pulse Out Amplifier 57
Delay Oscillator 57
1 ns Delay 58
Width Oscillator 58
1 ns Width 58
10 ns Width 58
SECTION 5 PARTS LIST AND SCHEMATICS 59
Parts List 59
Timing Board, 6040-2 59
Microprocessor Board, 6040-3 63
Power Supply Board, 6040-1 65
Annunciator Board, 6040-6 65
Miscellaneous Front Panel Assembly 65
Miscellaneous Top Assembly 65
Schematics
Please contact factory for copies.

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CONTENTS
ILLUSTRATIONS
Figure No. Page
Frontispiece Model 6040 Universal Pulse Generator
1-1 6040 Trigger and Output Pulse Timing 8
3-1 6040 Timing Circuits 45
3-2 Microprocessor Block Diagram 46
3-3 Simplified Interconnection Diagram 48
TABLES
Table No.
1-2 Instrument Status Byte 13
1-3 Error Status Byte 14
1-4 6040 Mainframe Default Settings 15
1-5 Menu Keys 26
1-6 Menu Keys for Stand Alone Operation 27
1-7 GPIB/RS-232 Error Messages 34
1-8 J8, Microprocessor to Module Interface Signals 52
1-9 J9, Microprocessor to Ed Interface Signals 53
1-10 Mainframe Memory Map 54

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SAFETY PRECAUTIONS
The following warnings, which appear both here and in the main body of the test, are to alert the user of
potential safety hazards and to encourage safe operating practices.
WARNING: To avoid possible electric shock, observe the following:
Do not operate with the cover removed. Exposed ac power is present even with the power switch off.
Be sure the ground conductor of the ac power cord connects the instrument to a solid earth ground.
WARNING: To remove all ac power from the unit, the line cord must be unplugged.
WARNING: To avoid accidental shock, unplug the line cord and turn the power off before checking or
replacing the fuse. For protection against fire, use only the specified fuse value. Do not attempt to
bypass or repair the fuse.
The following cautions, which appear both here and in the main body of the text, are to prevent
equipment damage that could result from improper operation.
CAUTION: The module must be installed with mainframe power off. A module can be damaged or
have its memory corrupted if inserted or removed from the mainframe with the power on.
CAUTION: Before plugging the instrument into a 234 V ac line, be sure the 115 V/230 V selection
switch is set to 230 V and a fuse of proper value is in place. Do not move this switch while the power is
on.

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UNIVERSAL PULSE GENERATOR
MODEL 6040
The Model 6040 System consists of a crystal-controlled programmable pulse/digital delay generator
mainframe and a family of optional plug-in modules. The 6040 itself generates TTL and ECL outputs at
rates to 100 MHz with 1 ns or less rise times and a 1 nanosecond resolution for pulse width, delay and
double pulse timing.
The interchangeable modules provide the instrument with additional capabilities such as faster
transition times, higher pulse amplitudes, and generating optical pulses.

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SECTION 1
SPECIFICATIONS
MODEL 6040 MAINFRAME CHARACTERISTICS
Timing Characteristics
INTERNAL REP RATE
Range: 0.01 Hz –100 MHz
Resolution: 4 digits
Accuracy: 0.01%
DELAY
Range: 0 –640 s.
Resolution: 1 ns or 5 digits, whichever is greater.
Jitter (rms): 25 ps or 0.01% of Delay, whichever is greater.
Accuracy: 0 to 9 ns. 1 ns; 10 ns to 640 s, 0.5 ns or 0.2% of Delay,
whichever is greater.
WIDTH
Range: 3 ns –640 s.
Resolution: 1 ns or 5 digits, whichever is greater.
Jitter (rms): 25 ps or 0.01% of Width, whichever is greater.
Accuracy: Width, whichever is greater.
PULSE SPACING
Minimum Pulse Separation: For Widths < 160 ns: 5 ns
For Widths 160 ns: 150 ns.
Trailing to leading edges.
Maximum Delay: For Delays < 160 ns: Delay (trig, period) - 5 ns.
For Delays 160 ns: Delay (trig, period) - 150 ns.
(For Double Pulses, see also Minimum Pulse
Separation.)
SINGLE CYCLE Depression of the ENTER or EXEC key will initiate a
single delay and width sequence.

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SPECIFICATIONS
Input Characteristics
TRIG IN External trigger to initiate delay and width sequences.
Range: 0-100 MHz.
Input Impedance: 50 Ω.
Slope: Selectable pos/neg.
Minimum Pulse Width: 3 ns.
Minimum Signal Amplitude: 100 mV.
Maximum Signal Amplitude: ± 7 V.
Threshold Range: ± 2.5 V.
Threshold Resolution: 10 mV.
Trigger Jitter: 20 ps rms (between TRIG IN and TRIG OUT).
MODULE DISABLE Allows the outputs on some modules to be remotely
disabled.
Disable: 4 V - 5 V. 5 mA sourcing current (into the 6040) or
contact opening.
Enable: 0 - 300 mV, 5 mA sinking current (from the 6040)
contact closure, or plug removed from jack.
Output Characteristics
PULSE OUT Provides the signal selected by the rep rate,
delay, width, and single/ double pulse settings.
Corresponds in timing to ECL OUT and to module outputs.
Amplitude: +4 Volts ((typ) into 50 Ω.
Transition Times: 1 ns rise time, 1.5 fall time.
Insertion Delay: 50 ns typical (between TRIG IN and PULSE OUT;
see Figure 1-1).
ECL OUT Provides an ECL version of PULSE OUT.
Amplitude: -0.8 V to -1.8 V into 50 Ω("low true" pulses).
Transition Times: 700 ps.
Insertion Delay: 50 ns typical (between TRIG IN and ECL OUT; see
Figure 1-1).

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SPECIFICATIONS
TRIG OUT Denotes the start of a liming cycle.
Amplitude: +2 V into 50 Ω. [+4 V into 100 Ω]
Transition Times: 3 ns (typ).
Pulse Width: 3 ns (typ).
Trigger Delay: 20 ns typical (between TRIG IN and TRIG OUT).
MODES With a module installed, four main operating modes are
available. The Mode selection is module dependent.
PULSE
Single Pulse: Conventional pulse generator with rate, delay and width
controlled by the 6040 mainframe (see Figure 1-1).
Double Pulse: A pair of identical pulses of the selected width with leading
edges separated by the selected delay.
External Drive: Produces pulses corresponding in rate and duty cycle
to an external pulse train. Available with some
modules.
EXTERNAL MODULATION Converts digital and analog electrical signals into their
optical equivalent.
IMPULSE
Single Impulse: A sub-nanosecond pulse of fixed width and amplitude,
with rate and delay controlled by the 6040 mainframe.
Double Impulse: A pair of Identical impulses separated by the selected
delay.
CW Provides a steady-state, adjustable power level.

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SPECIFICATIONS
Programming
GPIB IEEE-488 Remote interface with all functions and parameters
programmable and bus triggerable. Interface Functions:
SH1, AH1, T6, TE0, L4, LE0, SR1, RL1, PP0, DC1, DT1,
C0.
RS-232 Remote interface with all functions and parameters
programmable in full or half-duplex to 1200 baud and bus
triggerable.
LOCAL Pushbutton manual entry with panel LCD display.
General
DIMENSIONS 12.75" W x 5.25" H x 16" D (324 mm x 133 mm x
406 mm).
Rack Mount: 19" W x 6.97" H x 16" D (483 mm x
177 mm x 406 mm).
WEIGHT 16 lbs net (7.3 kg): 23 lbs shipping (10.4 kg).
Rack Mount: 5 lbs net (2.3 kg): 10 lbs shipping
(4.5 kg).
POWER 115/230 V ± 10 %. 50/60 Hz. 80 W.
AMBIENT TEMPERATURE Operating Range: 0° - 50° C (32° -122° F).
Specifications apply: 10° - 40° C (50° - 104° F).
Module Characteristics
PERMANENT MEMORY A ROM in the module determines the instrument's
allowable operating conditions and display units.
STORE Ten complete instrument settings can be stored in the
module's nonvolatile RAM. The module may be removed
without loss of these settings.

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SPECIFICATIONS
RECALL Stored settings can be manually recalled or bus
transferred to the mainframe. The setting in memory 0 is
activated automatically upon power-up or reset.
General
DIMENSIONS 3.75" W x 4.9 " H x 10" D (95 mm x 124 mm x
254 mm).
WEIGHT 2 lbs net (0.9 kg): 7 lbs shipping (3.2 kg).
Status Byte Summaries
Table 1-2. Instrument Status Byte
Bit
Description
7
Always zero
6
Always zero
5
Always zero
4
Always zero
3
Trigger has occurred
2
Overlap
1
PLL out of lock
0
Timing cycle in progress

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SPECIFICATIONS
Table 1-3. Error Status Byte
Bit
Description
7
Always zero
6
Always zero
5
Always zero
4
Always zero
3
Always zero
2
Always zero
1
Overrange
0
Unrecognized command
Module Status Byte
The Module Status byte is module dependent. Refer to the module's instruction manual.

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SECTION 2
OPERATING INFORMATION
General
POWER UP
When power is first applied, the mainframe performs a test to determine if a module is installed. If a
module is present, the limits for each module dependent parameter are transferred to the mainframe.
The memory is checked for any errors and the parameters in memory 0 are loaded into the mainframe.
If a module is not present, the parameters are set as indicated in Table 2-1.
Table 1-4. 6040 Mainframe Default Settings
LCD Power On Sequence
When the 6040 is first turned on, the display will show the software version number. If a module is
present, the LCD will then momentarily display "MEMORY CHECK," followed by the module I.D.
display. Without a module, the display will read "6040 No Plug-In."
MODE: Pulse
TRIG: Single Cycle (with other values set as follows)
Internal Trigger Rate = 1 kHz
External Trigger Threshold = 0 V
External Trigger Slope: +
TIMING: Width = 1 s
Delay = 1 s
Single Pulse
GPIB/RS-232: IEEE-488 Address = 6
Baud Rate = 1200
Full Duplex
Remote Enabled

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OPERATING INFORMATION
Module Installation
To install a module, turn the power off, slide the module in and tighten the mount screw knob.
Warm Up Requirements
The instrument should be allowed to warm up for 30 minutes before high precision measurements are
made. Less critical tests can be performed immediately after turn-on. Please refer to the module's
manual to determine if it requires an additional warm up period.
Safety Precautions
The safety warnings and cautions that appear in this manual are listed at the end of the table of
contents. Some modules have high voltage or laser outputs and additional safety precautions should be
taken. See the module manual for details.
Electrical Cables, Attenuators and Oscilloscopes
The electrical signal inputs and outputs have fast rise and fall times containing frequency-components
far in excess of 100 MHz. All signal handling components such as loads, cables, attenuators,
connectors and oscilloscopes should have a response exceeding 100 MHz and preferably 350 MHz.
Cable and load impedance mismatch will cause signal reflections and result in distorted waveforms and
measurement errors. Some sampling oscilloscopes will require attenuators to protect their inputs.
CAUTION: The module must be installed with mainframe power off. A module can be
damaged or have its memory corrupted if inserted or removed from the mainframe with the
power on.
WARNING: To avoid possible electric shock, observe the following-
Do not operate with the cover removed. Exposed ac power is present even with the power
switch off.
Be sure the ground conductor of the ac power cord connects the instrument to a solid earth
ground.

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OPERATING INFORMATION
TROUBLESHOOTING
To start, make sure that the line cord is plugged in all the way, and that the power-on key switch is in
the ON position. Verify that the 115 V/230 V selection switch is properly set for your area. (If it is not,
unplug the line cord and move the switch. Make sure the proper fuse in in place before plugging the
cord back in.)
With the line cord unplugged check the fuse. Make sure that it has not blown and that it is of the correct
value for the line voltage being used.
When ac power is applied, you should be able to hear the fan. The unit will not operate properly if the
side vents are blocked.
A thermal cutoff switch will shut off the power to everything but the fan should the temperature exceed
50oC. Power will be restored when the unit has cooled sufficiently. Make sure that the fan and the side
vents are not blocked, and that the fan is operating properly.
With the power off, make sure that the module is seated correctly in the mainframe.
LCD Contrast
If there are no characters on the LCD or the contrast is poor, a simple internal adjustment may solve
the problem (see the calibration procedure for details).
Cold Boot
If the instrument turns on, but is completely unresponsive to the keyboard or displays the error
message "Invalid Function." then the module's memory may have been corrupted causing the
instrument to "hang up." To correct for this, turn the unit off, then hold down the ENTER key and turn
the power back on. This will initialize the module's memory to its default settings (see the module's
manual for the specific values).
Quick Test
Since the 6040 uses a modular approach, operating problems can arise from either the mainframe unit
or the installed module: the problem must be localized to one or the other. To test the mainframe, turn
the power off, remove the module, and switch the power back on. Press the TRIG key until the internal
trigger parameter is displayed ("Trig Int: 1.000
kHz"). Press the 11} key, the {10x} key, the {5} key, and the ENTER key in sequence. The display will
read "Trg Int: 100.0 kHz."
Connect the TRIG OUT and PULSE OUT to channels A and B of an oscilloscope. Trigger the
oscilloscope on the leading edge of TRIG OUT. Set the oscilloscope for 1 us per division. Display the
PULSE OUT. A pulse of +5 V amplitude and 1 us duration should occur 1 s into the sweep.

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OPERATING INFORMATION
Press the TIMING key to display the Delay parameter ("Delay: 1.000 s"). Move the cursor (using the
{} key) to underline the 1 us decade. Now use the increment key {} to increase the Delay noting that
the incidence of PULSE OUT moves in 1 s steps. Repeat this with the Width parameter to change the
duration of PULSE OUT.
For quick testing of the module, repeal the above using the module output (an optical detector may be
necessary). Since some modules may have rep rate and width limitations, the specific values above
may have to be modified, but the general procedure is the same.
GPIB and RS-232 Problems
For remote operation from either GPIB or RS-232. the {GPIB/RS-232} key menu must be set to display
"Remote Enabled."
When using the GPIB, make sure that the GPIB cable is properly attached and that the address is
specified correctly. The default address is 6. but may be set between 1 and 30.
The 6040 will respond to remote commands only if the Remote Enable line (REM) is asserted. When
this happens the LCD will display "GPIB Remote Mode," and all keys except LOCAL will be disabled.
The LOCAL key allows the user to return to manual operation (unless the GPIB command LLO has
disabled it).
For the RS-232. again check the cable, but also verify that Baud Rate and Duplex are set
correctly.

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OPERATING INFORMATION
FRONT PANEL DESCRIPTION
Power Switch
The power switch, located in the lower left comer of the front panel, is keyed to prevent unauthorized
use. The key can be removed only when the switch is turned to the off position.
LCD Display
The 6040 has a 20-character liquid crystal display (LCD). This displays all menus and data while the
unit is being programmed from the front panel. In the following descriptions the display for each menu is
given.
LED Annunciator
The front panel has a set of seven LED indicators on the left side of the panel. The upper four LEDs.
labeled PULSE, IMPLS (Impulse), CW (Continuous Wave) and MOD (External Modulation), reflect the
current Mode setting. This allows continuous monitoring of the Mode setting.
The next two LEDs, labeled TRIG'D (triggered) and OVRLP (overlap), are used to indicate the status of
triggering in the Pulse and Impulse Modes. The TRIG'D LED is illuminated if there is a signal present at
the front panel TRIG IN jack that exceeds the threshold setting for an external trigger. The OVRLP LED
indicates that a potential triggering error exists. It blinks when the combination of rep rate. Width and
Delay results in some pulses not being generated. This occurs when the Minimum Pulse Separation
and Maximum Delay conditions are not met (see the Specifications section).
Finally, the bottom LED is labeled REM (remote) and indicates that the 6040 is under remote computer
control (via GPIB or RS-232).
Keypads
The 6040 has two keypads. The left keypad is used to control the operating state (Trigger, Timing,
Mode, etc.) and to modify existing parameters (increment/decrement value). The right keypad is used
primarlily to enter numeric data for new parameters. It is also used to toggle the states of certain
parameters (e.g. Single Pulse/Double Pulse) and to trigger the instrument under Single Cycle
operation.
WARNING: To remove all ac power from the unit, the line cord must be unplugged.

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OPERATING INFORMATION
Control Keypad
Some of these keys are dependent on the presence of a plug-in module. For example, the LEVEL,
STORE and RECALL keys function only with a module installed. The keys on the control keypad can
be divided into the following subsets: menu key, memory keys, function keys, and scan keys, as well as
the LOCAL and UNITS keys.
The five menu keys. MODE, TRIG. TIMING, LEVEL, and GPIB/RS-232, step through a number
of possible states or parameter displays, allowing the user to configure the instrument's operating
characteristics. The memory keys, STORE and RECALL, allow storage and retrieval of ten complete
instrument settings. The function keys are reserved for use with future modules. The scan keys, {}
{}, {}and () are used to modify parameters that have been previously entered.
The two remaining keys do not fall into any of the above categories. The LOCAL key returns instrument
control to the front panel from either GPIB or RS-232. The UNITS key allows the user to select between
different display units for the level parameter (an optical unit, for example, may allow the display of the
level settings in units of either Watts or dBm).
Numeric Keypad
The right keypad is similar to a calculator. It has keys for the decimal digits (0-9), the
decimal point (.), sign change (+/-), exponent (10x), backspace (BK SPC), enter (ENTER), and execute
(EXEC). ENTER and EXEC are used to terminate data entry and also to trigger a Single Cycle timing
sequence. The {+/-, SGL/DBL} key is used both to indicate negative values and to toggle between
Single Pulse and Double Pulse operation.
Connectors
There are three BNC connectors on the front panel. These are used in the Pulse and Impulse Modes to
monitor or trigger the pulse generator.
PULSE OUT provides waveform synchronized to TRIG OUT. The time position (with respect to TRIG
OUT) and duration of this output are set by the Delay and Width, respectively. PULSE OUT produces
pulses of a fixed +5 V amplitude (into 50 Ω) with 1 ns rise times and an 1.5 ns fall times.
PULSE OUT is nominally coincident with the plug-in module's output. The "module delay" (the fixed
time between the mainframe PULSE OUT and the module output) depends on the module being used
and is given in the module manual. In Impulse Mode, PULSE OUT has a fixed width of 5 ns (the Width
setting has no effect in Impulse Mode).
TRIG IN is the input for external triggers. It has a 50 Ωinput impedance, can take input voltages up to
±7 V dc or 7 V ac pk, and accepts frequencies up to 100 MHz.
TRIG OUT is the lime marker for the beginning of a timing cycle. TRIG OUT has fixed +3 V amplitude
(into 50 Ω), a 3 ns width, and transition times of 3 ns. In External Trigger operation, TRIG OUT will
occur 20 ns after the TRIG IN signal.