Concentrator Board for FERS-5200


FERS-5200 is a Front-End Readout System designed for large detector arrays, such as SiPMs, multi-anode PMTs, Silicon Strip detectors, Wire Chambers, GEM, Gas Tubes and others. 

FERS is a distributed and easy-scalable platform, where each unit is a small card that houses 32 or 64 channels with Front End electronics, A/D converters, trigger logic, synchronization, local memory, readout interface and (in some cases) detector bias voltage unit.

FERS is a flexible platform: keeping the same readout and control infrastructure, that is the same user interface, different types of front-end can be developed to fit a variety of detectors. In most cases, the front-end is based on ASIC chips that allow for high density, cost-effective integration of multi-channel readout electronics into small size and low power modules.

The Front End ASIC can implement an analog chain made of preamplifier, shaper, peak sensing and discriminator: this is the case of the model DT5202, based on two Citiroc-1A chip produced by Weeroc for SiPM readout.

One FERS unit can be used stand alone, without any additional hardware, just connected to the computer via USB 2.0 or Ethernet 10/100T. This is a cheap and an easy-to-use evaluation board of the specific ASIC chip housed on the FERS unit. Once the solution is validated, scaling up to thousands channels is immediate: multiple FERS units can be connected in a tree network, where the optical TDlink is the unique physical connection that guarantees high throughput data readout, slow control and accurate timing synchronization. 

One DT5215 (FERS Data Concentrator) can manage up to 8 TDlinks, each connected to 16 FERS units in daisy chain: in the case of the DT5202 (CITIROC 1A), it makes 8192 readout channels. The Data Concentrator is connected to the Host computer through 1/10 Gb Ethernet or USB 3.0. Multiple concentrator boards can be synchronized in order to further extend the total number of channels. 

A Linux-based Single Board Computer is embedded in the Concentrator board. It manages the data readout from the network of FERS units and the event data building according to the time stamp and/or trigger ID of the event fragments acquired by each unit. Sorted and merged data packets are then stored to the local memory and finally sent to the host computers through a fast 10 GbE or USB 3.0 link. Custom algorithms for data processing and reduction can be easily uploaded by the user into the embedded CPU. 

One computer, one Concentrator, thousands of channels

FERS-5200 is an extendable system: the same FERS unit can be used either as stand-alone or as part of the network tree for the readout of large arrays of detectors. In this way, the same card and same interface will be used, starting from the prototyping phase till the final implementation of the experiment. The core of the scalability of the FERS-5200 is the optical TDlink, which manages data stream, slow control and synchronization at once. The concentrator board DT5215 hosts 8 optical links, each one sustaining up to 16 FERS units in daisy chain. In the case of A5202 for SiPM readout, this means 8192 channels managed by a single Concentrator board.

Further scalability is possible synchronizing more than one Concentrator board.

  • DT5202 Front-End unit for SiPM readout with Weeroc CITIROC chip
  • Part of FERS-5200, the CAEN platform for the readout of large arrays of detectors (SiPM, MA-PMTs, Gas Tubes, Si detectors, …)
  • Scalability: from a single standalone FERS unit for prototyping to many thousands of channels, with simple tree network structure
  • Modularity: multiple FERS units can be distributed on large detector volume and managed by a Concentrator board.
  • Onboard bias voltage for SiPM
  • Up to 128 DT5202 FERS unit managed by a single Concentrator Board, i.e. up to 8192 SiPM pixels
  • Naked FERS unit A5202 for customizable mechanical frames available
  • Compactness: front-end cards with high channel density ASICs and effective connection to the detector backplane
  • Easy-synch: one single optical link (TDlink) for data readout, slow control and boards synchronization
  • Acquisition modes: spectroscopy (PHA), counting, time stamping with ToT
  • Concentrator Board DT5215 with multiple TDlink for event data building, processing and formatting

This product is sold with CAEN

Additional information

Number of Inputs

64 (= 2 CITIROC 1A chip)

Signal Polarity



Low Gain = 1.5pF/Cf (max gain = 60). High Gain = 15pf/Cf (max gain = 600)

Dynamic Range

Max: 400 pC (i.e. 2500 photo-electrons @ 106 SiPM gain)

Shaping Time

7 options from 12.5 to 87.5 ns


Min threshold = 1/3 photo-electron. Separate trigger lines per channel

External Trigger

From TDlink or T1 input

Bias Voltage

Common bias: 20 to 100V. Individual adjust: 8 bit, 4.5V range

Counting mode

Max. 20 Mcps, independent channels, 32 bit depth

Spectroscopy Mode

Simultaneous acquisition. 13 bit A/D conversion. Max conversion time = 10 μs

Timing Mode

0.5 ns resolution. Independent channels (merged list, time sorted) Spectroscopy information (low res) from ToT (0.5 ns). Linearization LUT

Trigger Time Stamp

48 bit, 2.5 ns step (~195 hours)

Zero/Ovr Suppression

Independent digital thresholds (LLD, ULD) and/or self-trigger mask

Readout/Control Interface

TDlink (6.25 Gbit/s) optical link with synch distribution. Ethernet 10/100T. USB 2.0

Power Requirements

Single power supply (+12V). Max current T.B.D.