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Unattended Data Acquisition Module for Unattended Monitoring Systems


  • Intended for neutron counting applications with multiple detectors
  • Dedicated to Nuclear Safeguards and nuclear material process monitoring in its life cycle
  • Shift Register and Pulse Train Recorder combined functions
  • 512 channel histogram of multiplicity data (Real+Accidentals and Accidentals)
  • Time-stamped lists saved to PTR-32 compatible file format
  • Unattended operation with data logging capability (two removable SD cards and USB stick)
  • Redundant storing mechanism implemented for higher reliability in unattended operation
  • Pulse pair resolution and minimum pulse width detection bigger than 10 ns
  • 8 inputs on LEMO connectors (TTL, 50 Ω) with independent counting capability
  • Special video output (HDMI) to externally monitor the state-of-health of the device
  • High power high voltage supply output (+2000 V @ 500 μA)
  • 2 high power low voltage outputs (+5V / +12V @ 1 A)
  • Gigabit Ethernet and USB2.0 interfaces
  • Provided with CAEN ShiftRegister readout software and SDK tool for custom development
  • Compliant to INCC software package
  • Fully remotely controllable by Web Interface
  • 19” rack mount capability


The R7780 is a complete readout, acquisition and analysis module for up to 8 neutron detectors that can work in unattended mode. The device combines the functions of a Shift Register and a Pulse Train Recorder. It is provided in mechanics compliant to 19” racks. The eight single-ended TTL inputs (LEMO) feature independent counting capability. Moreover, adjustable input thresholds give the possibility to compensate TTL signal voltage drops in case of long- distance use.

The internal 100MHz sampling clock fits for high count-rate applications and the on-board intelligence synergy of a FPGA and a Single Board Computer (an ARM CPU running Linux) makes it possible to provide time-stamped lists and the overall neutron counting information (coincidence timing, multiplicity distributions of coincident events, etc.) required for the analysis in Nuclear Safeguards and nuclear material process monitoring.

After the start-up sequence based on a programmable configuration file, the device can collect data without external control on a local non-volatile memory. Two SD cards, externally accessible for insertion/extraction, store all measurement results and log information in two identical copies for redundancy reasons. The presence of a OTG USB port allows the automatic data retrieval by a USB stick.

The R7780 is equipped with a video output (HDMI) to connect an external display for monitoring the state of the device and acquisition information. High power outputs are available as well: one high-voltage channel for the detector biasing and two different low-voltage channels (+5V and +12V) to power the front-end electronics such as preamplifiers and discriminators.

The device can also operate in attended mode controlled by an external host computer using a point‐to‐point direct connection through the USB 2.0 link and a remote network connection through the Gigabit (1000Base-T) Ethernet port.

The R7780 is fully supported by CAEN ShiftRegister control software which configures the device and handles the data acquisition. In attended mode, the raw data can be saved to binary files on the host computer for offline analysis (supported PTR-32 format compatible with the INCC software*). Users can take advantage of the provided CAENSR library for custom development. Complete device control, including firmware upgrade, is also possible by Web Interface.

*INCC Software Users Manual: http://lib-www.lanl.gov/la-pubs/00326587.pdf

Technical Specifications

From Factor 

1U width, 265mm depth
compatible with 19” rack




8 signal inputs 

Single-ended TTL (Zin = 50 Ω) 

LEMO 00 female socket 

Pulse width detected bigger than 10 ns 

Internal fast comparator with a software-programmable threshold (from 0 to 5V with a resolution of 0.05V) common to each group of 4 channels to compensate for cable length signal attenuation 


High Voltage output 

SHV plug 

+5V, +12V 

Low voltage outputs 

BNC jack receptacle 

SD1, SD2 

Memory slot for SD card 


OTG USB2.0 port for USB stick 

Type-A socket 


Video output for monitoring 

Type-A HDMI socket 


USB2.0 communication port 

Type-B socket 


Gigabit Ethernet port 

RJ45 shielded jack 

Power In 

9-36V DC rack power input 


Single channel for the detector power supply:
Output Bias Voltage (Vset) = 0 to +2000 V
Output Bias Current (Iset) = 500 μA (max.)
Vset Resolution = 1 V
Vmon Resolution = 1 V
Imon Resolution = 1 μA
Ramp‐Up/Ramp‐Down = 1 ÷ 500 V/s in steps of 1V


Two channels for the preamplifier power supply:

  • +5 V @ 1 A
  • +12 V @ 1 A

ARM Cortex‐A9 quad core @ 1 GHz running Linux® 


Cyclone V GX 

  • Unattended: after the start-up sequence, all data are logged on-board without external intervention
  • Attended: the device works under full control of an external PC (INCC software compliance) transmitting raw data for further analysis; time-stamped lists are saved to binary files compatible with PTR-32 format
  • Terminal: attended access to the device operating system
  • Works in unattended operation
  • Coincidence and Multiplicity measured data, configuration and log information files, firmware files are locally stored on non-volatile memory
  • Two removable 32GB SD cards replicate same folder structure and contains same data for redundancy reasons to prevent from non-volatile memory device failures
  • LED indicators inform on the SD card state
  • Attaching a USB stick activates the fully automatic copy of all data from non-volatile memory; a LED indicator shows the state of the process
  • Gate width: 0.05 μs to 1.3 ms in steps of 0.05 μs below 1 μs and 0.5 μs above 1 μs
  • Pre-delay: 0 μs to 100 μs in steps of 0.05 μs below 1 μs and 0.5 μs above 1 μs
  • Delay between the Reals+Accidentals gate and the Accidentals gate: 4 ms
  • Measurement time: between 1 s and 43600 s (12 h)
  • Reals+Accidentals and Accidentals counters number of counts: up to 2×1014 per measurement time
  • Internal clock: 100 MHz
  • Pulse pair resolution: bigger that 10 ns
  • Maximum number of multiplicity bins for Accidentals and Reals+Accidentals: 512 (up to 4×109 count per each bin); a lower number of bins is software configurable

Gigabit Ethernet, 1000Base-T

Configuration, operation, and data taking in attended mode


Version 2.0 

Configuration, operation and data taking in attended mode

Virtual COM port for local communication with a Windows-based computer

  • Windows® and Linux® support:
  • Drivers for the communication links
  • SDK tool including CAENSR library and demo code for custom development
  • CAEN ShiftRegister control software
  • Compatibility with INCC software
  • Web Interface (Board information retrieval and configuration, files management, data readout, firmware upgrade)

Integrated primary power supply unit 9-36V DC:

  • 1 A @ 28 V
  • 1.17 A @ 24 V
  • 2.4 A @ 12 V
  • 3.22 A @ 9 V

Measured in full load conditions (12V and 5V preamplifier outputs on 1A, HVPS output on 2kV@500μA, SBC on, fan on, USB stick in, 2 SD cards in, Ethernet link active)

Ordering Options

Code Description
WR7780XAAAAA R7780 - CAEN Shift Register Multiplicity and Time Recorder  RoHS