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751 Digitizer Family

8-4 / 4-2 Channel 10-bit 1-2 GS/s Digitizer
The 751 is a family of 10-bit, 1 GS/s Flash ADC Waveform Digitizers available in three form factors: VME (8 input channels), NIM (4 input channels) and Desktop (4 input channels). Considering the sampling frequency and the bit number, it is well suited for fast signals as the ones coming from fast organic, inorganic and liquid scintillators coupled to PMTs or Silicon Photomultipliers, Diamond detectors and others.

x751 can work also as a 10-bit, 2 GS/s Flash ADC Waveform Digitizer when operating in Dual Edge Sampling (DES) mode, inteleaving pairs of input channels.

The acquisition capabilities of x751 take advantage of the multi-buffer organization of the memories. The data stream is continuously written in a circular memory buffer. When the trigger occurs, the digitizer writes further samples for the post trigger and freezes the buffer that can be read by one of the provided readout links. The acquisition can continue without any dead time in a new buffer.

Two memory sizes are available according to the different versions of the x751 model: 1.8 - 3.6 MS/ch or 14.4 - 28.8 MS/ch.

x751 digitizer is provided with FPGAs that can run Digital Pulse Processing (see the box below). In addition to the existing firmware, CAEN is available to collaborate with customers to develop custom solutions.

751 family supports multi-board synchronization allowing all ADCs to be synchronized to a common clock source and ensuring Trigger Time Tag alignment. Once synchronized, all data will be aligned and coherent across multiple x751 boards.

A common acquisition trigger signal can be provided externally, via front panel digital input connector, or via software. Alternatively, each channel can generate a trigger request when the input pulse goes under/over a programmable threshold; the trigger requests can be used either locally by the channel (independent triggering with DPP firmware) or processed by the board to generate a common trigger causing all the enable channels to acquire an event simultaneously (default firmware). The trigger from one board can be provided on a front panel digital output connector.

751 family supports multi-board synchronization making a multi-board system where all ADCs result to be synchronized to a common clock source, and ensuring Trigger Time Tag alignment. Once synchronized, all data will be aligned and coherent across multiple x751 boards.

Refer to the following links for specific information on the different form factors: V1751, VX1751, DT5751, N6751.


CAEN Digitizers can be operated as pure waveform recorders or can run special algorithms to process the digitized pulses and extract a set of significant information like energy, pulse shape and precise timing.Each acquisition mode makes use of a specific firmware and software to tailor the digitizer capabilities to the user's needs.
Digital Waveform Recording with Zero Suppression for trigger-less acquisition system
Logo Software DPP ZLE
Digital Pulse Processing for the Zero Length Encoding Firmware
Logo Software DPP ZLE CONTROL
Demo Software for DPP-ZLEplus Management
 (*) DPP-ZLEplus doesn't support DES mode (2 GS/s sampling frequency).
GENERAL Form Factor
1-unit wide, 6U VME64/VME64X
1-unit wide NIM
154x50x164 mm3 (WxHxD) Desktop
ANALOG INPUT


Channels
8-4 channels
single ended / differential (VME)
4-2 channels
single ended / differential (NIM, Desktop)

Impedance
50 Ohm single ended
100 Ohm differential
Connector
MCX single ended
AMP MODU II differential



Full Scale Range
1 Vpp (default)
0.2 Vpp (on request)
Bandwidth
500 MHz




Offset
Programmable DAC for DC offset adj.
Range: ± 0.5 V @ 1 Vpp, ± 0.1 V @ 0.2 Vpp
DIGITAL CONVERSION


Resolution
10 bits
Sampling Rate
250 to 1000 MS/s
symultaneously on each channel (double in DES mode)
ADC CLOCK GENERATION Clock source: internal/external
On-board PLL provides ADC sampling clock generation from an internal (50 MHz loc. oscillator) or external (front panel CLK-IN connector) reference
TRIGGER


Trigger Source
Self-trigger: channel over/under threshold for either Common or Individual (DPP only) trigger generation
External-trigger: Common by TRG-IN or individual by LVDS connectors (VME and DPP only)
Software-trigger: Common by software command
Trigger Propagation
TRG-OUT (VME) / GPO (NIM, Desktop) digital output

Trigger Time Stamp
Standard FW, DPP-ZLE: 31-bit counter, 16 ns resolution, 17 s range
DPP-PSD FW: 32-bit counter, 1 ns resolution, (4 s range), expandable to 64-bit
MEMORY 1.835 MS/ch (3.6 MS/ch in DES mode) or 14.4 MS/ch (28.8 MS/ch in DES mode)
Multi-Event Buffer with independent read and write access divisible into 1 ÷ 1024 buffers
Programmable event size and pre-post trigger
SYNCHRONIZATION


Clock Propagation
Daisy chain (VME only) through CLK-IN/CLK-OUT connectors
One-to-many clock distribution from
an external clock source
Clock Cable delay compensation
Acquisition Synchronization
Sync Start/Stop through digital I/O (S-IN, TRG-IN or GPI input, TRG-OUT or GPO output)
External Trigger Time Stamp reset
LVDS I/O (VME only) 16 general purpose LVDS I/Os controlled by FPGA
Busy, Data Ready, Memory Full, Individual Trg-Out and other functions can be programmed
An Input Pattern from the LVDS I/Os can be associated to each trigger as an event marker
ANALOG MONITOR
(VME only)
12-bit/100 MHz DAC FPGA controlled output with four operating modes:
Trigger Majority / Test Pulses / Memory Occupancy / Voltage Level
COMMUNICATION INTERFACE


Optical Link
CAEN CONET proprietary protocol,
up to 80 MB/s transfer rate
Daisy chainable: it is possible to
connect up to 8/32 ADC modules to a
single Optical Link Controller (Mod.A2818/A3818)
USB (NIM and Desktop direct, VME via V1718 bridge)
USB 2.0 compliant

VME
VME 64X compliant
Data transfer mode: BLT32, MBLT64 (70 MB/s using CAEN Bridge), CBLT32/64, 2eVME, 2eSST (up to 200 MB/s)
POWER CONSUMPTIONS
Desktop
1.8 A @ 12 V (Typ.)
NIM
3.9 A @ +6 V
120 mV @ -6 V
VME
6.5 A @ +5 V
200 mA @ +12 V
300 mA @ -12 V
Code Description
WV1751BXAAAA OBSOLETED | V1751B - 4/8 Ch. 10 bit 2/1 GS/s Digitizer: 3.6/1.8MS/ch, EP3C16, DIFF
WV1751CXAAAA V1751C - 4/8 Ch. 10 bit 2/1 GS/s Digitizer: 28.8/14.4MS/ch, EP3C16, SE
WV1751XAAAAA V1751 - 4/8 Ch. 10 bit 2/1 GS/s Digitizer: 3.6/1.8MS/ch, EP3C16, SE
WVX1751BXAAA OBSOLETED | VX1751B - 4/8 Ch. 10 bit 2/1 GS/s Digitizer: 3.6/1.8MS/ch, EP3C16, DIFF
WVX1751CXAAA VX1751C - 4/8 Ch. 10 bit 2/1 GS/s Digitizer: 28.8/14.4MS/ch, EP3C16, SE
WVX1751XAAAA VX1751 - 4/8 Ch. 10 bit 2/1 GS/s Digitizer: 3.6/1.8MS/ch, EP3C16, SE
WDT5751XAAAA DT5751 - 2/4 Ch. 10 bit 2/1 GS/s Digitizer: 3.6/1.8MS/ch, EP3C16, SE
WN6751XAAAAA N6751 - 2/4 Ch. 10 bit 2/1 GS/s Digitizer: 3.6/1.8MS/ch, EP3C16, SE
WN6751CXAAAA N6751C - 2/4 Ch. 10 bit 2/1 GS/s Digitizer: 28.8/14.4MS/ch, EP3C16, SE
WPERS0175102 x751 Customization - 200mVpp Input Range, SE
Model Package Function Description Compare
All - Reset
720 Digitizer Family Waveform Digitizers Digitizer Families 8/4/2 Channel 12-bit 250 MS/s Digitizer
724 Digitizer Family Waveform Digitizers Digitizer Families 8/4/2 Channel 14-bit 100 MS/s Digitizer
725 Digitizer Family Waveform Digitizers Digitizer Families 16/8 Channel 14-bit 250 MS/s Digitizer
730 Digitizer Family Waveform Digitizers Digitizer Families 16/8 Channel 14-bit 500 MS/s Digitizer
740 Digitizer Family Waveform Digitizers Digitizer Families 64/32 Channel 12-bit 62.5 MS/s Digitizer
742 Digitizer Family Waveform Digitizers Digitizer Families 32+2 / 16+1 Channel 12-bit 5 GS/s Switched Capacitor Digitizer
743 Digitizer Family Waveform Digitizers Digitizer Families 16/8 Channel 12-bit 3.2 GS/s Switched Capacitor Digitizer
751 Digitizer Family Waveform Digitizers Digitizer Families 8-4 / 4-2 Channel 10-bit 1-2 GS/s Digitizer
761 Digitizer Family Waveform Digitizers Digitizer Families 2/1 Channel 10-bit 4 GS/s Digitizer
Manuals Last Update
DT5751 User Manual 12 June, 2017
N6751 User Manual 12 June, 2017
V1751 & VX1751 User Manual 12 June, 2017

Precautions for Handling Storage and Installation

Application Notes Last Update
In this application note, we describe the capability of the Digitizer series x720 (12 bit, 250MS/s) to perform neutron-gamma discrimination based upon the digital pulse shape analysis. The digitizer runs the preliminary version of the DPP-PSD firmware for the digital charge integration and neutron-gamma discrimination. AN2506 - Digital Gamma Neutron discrimination with Liquid Scintillators 19 November, 2011
In this application note, Pulse Shape Discrimination between neutrons and gamma rays in liquid scintillators is studied by using DPP-PSD firmware running on CAEN digitizers. The dependence of the Figure of Merit on the digitizer sampling rate and resolution is experimentally determined. Based on "Pulse shape discrimination with fast digitizers", L. Stevanato et al, NIMA 748 (2014) 33-38, DOI: 10.1016/j.nima.2014.02.032 AN3250 - Pulse Shape Discrimination with different CAEN digitizers running DPP-PSD firmware 13 July 2014
In this note we focus our attention on the techniques for time measurement using waveform Digitizer. It describes one of the algorithms typically used for this measurements, it implementation and their performances, which are obtained in some benchmark tests. This note shows that Digitizers are capable to measure time stamps with higher accuracy (few ps resolution) compared to commercial analog solution composed by CFD and TDC modules. AN3251 - Time Measurements with CAEN Waveform Digitizers February, 2015
Slide Presentations Last Update
SP5148 - Digital systems for Multi-Parametric analysis in Physics Applications (India - March 2016) March, 2016
Catalog Last Update
2016-2017 Catalog Modular Pulse Processing Electronics / Waveform Digitizers CAEN Digitizers are platform independent instruments housing high speed (up to 5 GS/s) multichannel flash ADC, with local memory and FPGA for Digital Pulse Processing. Available in VME, NIM, Desktop. Up tp 14-bit resolution, 1 to 64 channels, programmable PLL, VME64X, Optical Link and USB 2.0 interfaces, Software Tools for Windows and Linux, Memory buffer: up to 57MS/ch (max. 1024 events), Firmware and Software for Digital Pulse Processing (DPP) and Waveform Recording 2016-2017 Product Catalog Section 03a - Modular Pulse Processing Electronics / Waveform Digitizers March 2016
Scientific Articles Last Update
The performance of a CAEN DT5751 digitiser for nuclear safeguards and security applications is discussed. The pulse shape processing firmware embedded in the digitiser was tested with a EJ-309 liquid scintillator, exposed to gamma and neutron radiation from radioactive sources and from a Van de Graaff and cyclotron-based accelerator. PAEPEN Jan, et al. JRC Scientific and Policy Report (2013), European Commission, Joint Research Centre, Institute for Reference Materials and Measurements, JRC Publication N°: JRC87790, DOI: 10.2787/87780, ISBN: 978-92-79-35403-8. AR3184 - Use of a CAEN digitiser for nuclear safeguards and security applications with a scintillator detector- JRC Scientific and Policy Report 2013
This paper presents a system devised to separate neutron and gamma ray pulses through pulse shape discrimination (PSD) using liquid scintillators and SiPM technology. The raw SiPM pulses are processed using CAEN digitizer (V1730 and V1751). Pulses were processed either through the on-board Digital Pulse Processing (DPP) PSD algorithms, allowing the digitisers Field Programmable Gate Array (FPGA) to perform the charge integration, or the waveform was simply recorded for post-processing with external, in-house analysis software. M P Taggart et al 2016 J. Phys.: Conf. Ser. 763 012007 - DOI:10.1088/1742-6596/763/1/012007 AR5553 - Neutron-gamma discrimination via PSD plastic scintillator and SiPMs 11 May, 2016
Data Sheet Last Update
The 751 is a family of 10-bit, 1 GS/s Flash ADC Waveform Digitizers. It can work also as a 10 bit, 2 GS/s Flash ADC Waveform Digitizers when operating in Dual Edge Sampling (DES) mode, interleaving pairs of input channels. It is available in three form factors: VME equipped with 8 input channels (4 in DES mode), NIM and Desktop equipped with 4 input channels (2 in DES mode). x751 digitizers can run two Digital Pulse Processing firmware for Physics Applications: DPP-PSD. DPP-ZLEplus. DS3157 - 751 Digitizer Family (8-4/4-2 Channel 10-bit 1-2 GS/s Digitizer) Data Sheet 20 May, 2016

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