BNC 745-T User manual

MODEL 745-T
FOUR CHANNEL DIGITAL DELAY/ PULSE GENERATOR
User Manual
The MODEL 745-T
Four high resolution delay channels
0.25ps delay resolution
<25ps RMS jitter max (5ps for short delay)
20s delay range (relative/absolute reference)
Three trigger sources: external, internal or command
Positive or Negative trigger slope
Single, Repetitive or Burst trigger mode
Gate mode
External trigger prescaler (pulse picking)
Tunable output (magnitude 2-5V, width 100ns-10µs)
50 Ωload
T0 reference output
Clock output
Gate input
High precision internal clock (OCXO 50ppb)
USB
Ethernet interface (Web page)
Options:
4 auxiliary high resolution delay channels (1.25ns, 2 to
5V Amplitude but common tuning)
The MODEL 745-T digital delay generator provides four
independent high resolution digital delay channels. The
rms jitter between the trigger and any outputs is 25ps +
delay x 10-8 max. which ensures a high performance
delay. The device can be triggered by different ways:
External trigger via a BNC input, Internal trigger and
Software command trigger, each one with repetitive,
single and burst trigger modes.
3/2/18
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[email protected], Call 800-234-7858 or Live-Chat @ www.berkeleynucleonics.com
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CONTENT
1- GENERAL INFORMATION.................................................................................................... 4
What do you need to get started....................................................................................................... 5
Unpacking Caution .......................................................................................................................... 5
Operating temperature..................................................................................................................... 5
Self-test............................................................................................................................................. 5
The device software.......................................................................................................................... 5
Power fuses...................................................................................................................................... 5
RAM with battery back up................................................................................................................ 5
2- SPECIFICATIONS.................................................................................................................... 6
3- FRONT PANEL OVERVIEW.................................................................................................. 7
LCD screen ...................................................................................................................................... 7
RUN/STOP Button ........................................................................................................................... 7
BNCs ................................................................................................................................................ 7
Optional BNC................................................................................................................................... 7
4- REAR PANEL OVERVIEW..................................................................................................... 8
Power Switch.................................................................................................................................... 8
T0 output.......................................................................................................................................... 8
Clock BNCs...................................................................................................................................... 8
AUX BNCs........................................................................................................................................ 8
Ethernet Port.................................................................................................................................... 8
USB Port.......................................................................................................................................... 8
5- MENU STRUCTURE (NAVIGATING THE MODEL 745-T).............................................. 9
6- OPERATING INFORMATION............................................................................................. 14
Operating Principles...................................................................................................................... 14
Timing principle using external trigger......................................................................................... 16
Timing principle using internal trigger.......................................................................................... 18
Timing principle using Burst mode................................................................................................ 19
7- OPERATING EXAMPLE....................................................................................................... 20
Default value.................................................................................................................................. 20
Initial setup .................................................................................................................................... 20
Setting up the instrument (Recurrent mode) .................................................................................. 20
Setting up the instrument (Single shot mode)................................................................................. 20
Setting up the instrument (Burst Mode)......................................................................................... 20
Stop the generator.......................................................................................................................... 21
8- PROGRAMMING.................................................................................................................... 22
Serial communication (USB port).................................................................................................. 22
Ethernet connection/communication.............................................................................................. 22
Command structure (Ethernet and USB connection)..................................................................... 22
Web Page control/communication................................................................................................. 29
9- ANNEX A.................................................................................................................................. 30
10- ANNEX B.................................................................................................................................. 32
3/2/18
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EDITION
Ed. Date Description
1 07/09/2015 Creation
2 04/11/2015 Modification: channels T1-T8 become channels A-H
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1- GENERAL INFORMATION
The MODEL 745-T device provides four high precision independent delay channels. Access to these
four outputs (A-D) is given by four BNC connectors on the front panel. The achieved delay resolution
is about 0.25ps, and trigger-to-channel jitter is less than 25ps (Annex B). A-D can deliver up to 5V, 2ns
rise time max (9-Annex A), into 50Ω. Amplitude and width are adjustable on each output channel
either programmed from the front panel or via Ethernet.
A T0 output pulse is also available. It gives a time reference for each generated delayed output.
This high accuracy and precision device is suitable for system/experiment in science or industry
that requires reliable timing solution.
The MODEL 745-T also provides four optional delay channels to front panel E-H with a delay
resolution of 1.25ns, trigger-to-channel jitter less than 50ps with a common 2 to 5V tunable
amplitude.
The internal timebase reference is a OCXO with a stability of 50ppb.
The device offers three operating trigger modes, repetitive (internal or external source), single
shot (internal, external or asynchronous source) and a burst mode (internal, external or
asynchronous source).
A Web page (accessed via Ethernet link) provides a simple method to configure the settings for
each channel, amplitude, width, trigger source, trigger mode and to control operation. You can
save and recall settings.
A serial communication is also available via an USB port.
Instrument Options
745-4C-GOC Standard device
745-8C-GOC Extension to 8 channels (4 optional channels with 1.25ns resolution)
Package Contents
The box you receive should contain the following:
-MODEL 745-T Digital Delay Generator
-PDF user manual and Labview VIs can be downloaded at:
-http://www.berkeleynucleonics.com/support
-Certificate of calibration
BNC product:
For more information about BNC product see our web site: http://www.berkeleynucleonics.com/.
3/2/18
Berkeley Nucleonics Corporation, 2955 Kerner Blvd. San Rafael, CA 94901
[email protected], Call 800-234-7858 or Live-Chat @ www.berkeleynucleonics.com
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What do you need to get started
To set up and use the MOD745, you need the following items:
•MODEL 745-T Digital Delay Generator,
•MODEL 745-T user manual
Unpacking Caution
The MODEL 745-T is shipped in an antistatic package to prevent electrostatic damage to the device.
Electrostatic discharge (ESD) can damage several components on the device. Remove the device
from the package and inspect the device for loose components or any sign of damage. Notify BNC if
the device appears damaged in any way.
Caution:
Before device plug in, be sure to set the right voltage with the line voltage selector. It operates from
90V to 240 V.
Do not apply any voltage to either the shields or the output BNCs.
Operating temperature
The MODEL 745-T can be operated where the ambient air temperature is 10°C to 35°C and can be
stored in ambient temperature from - 10°C to + 60°C. The MODEL 745-T is cooled by air circulation.
Self-test
The unit model, firmware version, serial numbers and the result of self-test procedure will be
displayed one minute after power on. After 30s if the test is good then “self-test” disappears and the
device can be used. If the test is not ok then “self-test” stays displayed and the device is locked.
The device software
Labview Vi’s are provided with the MODEL 745-T device. They allow users to control and/or configure
the equipment as planned. These Vis can be integrated in a top-level Vi where several devices are
controlled.
The communication is done with an Ethernet connection.
Power fuses
The MODEL 745-T is protected against short circuit by means of one fuse according to nameplate of
the power supply (F2.5H250V).
RAM with battery back up
The MODEL 745-T has a RAM with battery backup in which settings of the instrument can be stored
(Lithium battery ref 2032).
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2- SPECIFICATIONS
Delays
Channels 4 independent delay outputs
Range 0 to 20 seconds
Resolution 0.25 ps
Jitter 25ps RMS + delay x 10-8 (external
trigger to any output) Annex
20ps RMS + delay x 10-8 (Channel
to channel) Annex
< 5ps RMS for short delay
(Channel to channel)
Accuracy < 250ps + delay x 10-8
Time base 200 MHz, 50 ppb
Trigger source
Internal 2 Timers tunable in Hz or ns
1Hz to 1MHz, 1Hz resolution
1µs to 4s, 5ns resolution
External Repetition rate < 1MHz
Prescaler : 1 to 216-1
Trigger level, from 0.1 to 5V,
Internal load: 50Ω
Positive or negative slope
Minimum trigger delay < 60ns
Trigger mode
Single, repetitive or burst
Burst specs. Pulse number: 2 to 216-1
Period: 1000ns to 1s
Gate Mode
2 settings: General or Individual
Gate source Active high, Rep rate <100kHz
Output A-D (T1-T4) BNC connector
Amplitude 2 to 5V, 0.1V resolution
Width 100ns to 10 µs, 5 ns resolution
Load 50 Ω
Rise time < 2ns max, 900ps typical
Fall time < 5ns max, 2ns typical
Clock Input
Frequency 10 or 80 MHz, 50% duty cycle.
Ask factory for custom clock
frequency.
Clock Output
Frequency 10 or 80MHz (directly related to
the input clock)
Signal +/- 1 V, square
USB Port
Communication serial, baudrate 38400
User Memory
Up to 4 sets of MODEL 745-T parameters can be
stored/recalled via Front Panel or Telnet
General specifications
Size 215 x 245 x 135 mm
Power 50 W – 110 to 240 V
LEDs Orange: Trigger on
Software
Control panel Web page from embedded web
server for IE, Firefox or Chrome
Options
745-8C: 4-auxiliary delay output extension
Delay
Channels: 4 independent delay outputs
Range: 0 to 20 seconds
Resolution: 1.25ns
Jitter: 50ps RMS + delay x 10-8
(External trigger to any output)
Accuracy: < 1ns + delay x 10-8
Output E to H (T5 to T8)
Amplitude: 2 to 5V
Width: 100 ns to 10ms; 5ns resolution
Load: 50Ω
Rise and Fall time < 5 ns
Connector: BNC on front panel
3/2/18
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3- FRONT PANEL OVERVIEW
The MODEL 745-T front panel is composed of several kinds of elements: the user interface which
consists of a keyboard and an LCD display that allows the user to program various settings and to
interact with the device in local mode, 4 status LEDs, BNC connectors.
Figure - 1. Front panel
LCD screen
The screen is a 4.3” touch screen.
RUN/STOP Button
Global RUN/STOP. It enables to RUN or STOP all output channels.
BNCs
One input Trigger, one Gate input and 4 independent output channels (A – D) are available. The
output voltage is tunable from 2 to 5V for each output independently and each one has to be
terminated in 50Ω.
The input Trigger BNC connector provides a trigger signal operating up to 50 kHz.
Optional BNC
The four optional output (E – H) connectors are 50Ω impedance with adjustable amplitude, delay
and width.
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4- REAR PANEL OVERVIEW
All optional output connectors/modules appear on that side of the device. The other features are
listed below.
Figure - 2. Rear panel
Power Switch
The unit is turned on by depressing the Power button. The MODEL 745-T can be operated from 100
to 240V at a line frequency of 50-60Hz.
T0 output
A reference pulse output is available. It delivers a fixed amplitude pulse with adjustable width.
Terminated in 50Ω.
Clock BNCs
Clock input and clock output connectors are available. The CLK IN connector accepts either 10MHz or
80MHz (or custom frequency) clock frequency. The clock output (CLK OUT) comes from the CLK IN
connector or from the internal oscillator – if clock in signal not present.
AUX BNCs
The AUX connector is not used so far.
Ethernet Port
A RJ45 Ethernet connector is available to control the MODEL 745-T with a computer. See § 8-.
USB Port
A female USB connector can be available allowing serial communication with the MODEL 745-T. See
Chapter 8 – Programming for command syntax.
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[email protected], Call 800-234-7858 or Live-Chat @ www.berkeleynucleonics.com
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5- MENU STRUCTURE (NAVIGATING THE MODEL 745-T)
A three level Menu is available:
•A main menu to display settings
•Sub-Menus to select the parameter to set
•Keyboard to set the new parameter value
With 8 channel option
Here is given a presentation of the display menu for a 8 Channel Unit.
From the main menu (Figure - 3) the user can access every MODEL 745-T settings by pressing the
selected parameter zone.
Figure - 3. Main Display
Main Display
Settings
name
Description
Special
Pulse Output
Channel settings: trigger, amplitude, width,
delay, reference, gate
Use the Pulse Channels bar
to change the displayed
channel
Internal
Frequencies
Frequency or Period settings of internal trigger
generator 1 & 2
Press the P button to
display period settings
General
Clock, gate, store/recall and network settings
Press General in the Setup
box to display the menu
External
trigger
Trigger settings: threshold, slope and
prescaler
Press Ext Trig in the Setup
box to display the menu
Burst
Input clock setting: 10 or 80MHz.
Press Burst in the Setup
box to display the menu
Trigger
Manual trigger button
Channel
status
Display the current channl status
Press the zone to clear
channel status
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Channel Setting Display
Channel Tx can be channel A to H.
Displayed
name
Description and settings
TX
TRIG=
To select Trigger source
OFF= Trigger signal is inhibited
IN1= Trigger signal coming from internal frequency 1
IN2= Trigger signal coming from internal frequency 2
EXT= Trigger signal coming from the front panel (TRIG IN)
SS1= Single Shot trigger synchronous with internal freq. 1
SS2 = Single Shot trigger synchronous with internal freq. 2
SSE= Single Shot trigger synchronous with trigger input
LSS = Software Single Shot trigger
BST = Pulse train Trigger sync. With internal freq. or
trigger input
TX RET=
To select the channel delay reference: T0 and A to H
TX
Delay=
To adjust Output pulse delay of channel (A to D 1ps resolution display, E to H 1.25ns
resolution display).
TX
Ampl=
To adjust Output pulse amplitude of channel A to H.
TX
Width=
To adjust Output pulse width of channel TX
TX Gate
To set Channel Gate mode On or Off (available if general Gate mode is set to “Channel
Gate”) of Channel A to H
RETURN
MENU
To Return to main menu
Figure - 4. Channel settings
Note:
To escape from a submenu and go back to the main menu (RETURN MENU item in tables), the user
has to touch the bottom bar center and slide up his finger (see Figure - 4).
To generate a pulse with a Single Shot setting (SS1, SS2, SSE or LSS), the user has to press the TRIG
button displayed on the general menu.
Next channel
Escape
Previous channel
3/2/18
Berkeley Nucleonics Corporation, 2955 Kerner Blvd. San Rafael, CA 94901
[email protected], Call 800-234-7858 or Live-Chat @ www.berkeleynucleonics.com
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