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Multichannel Analog Front-End for SiPM

  • SiPM signal preamplification and shaping
  • 32/64 input channels
  • Input dynamic range up to 6000 photoelectrons
  • Integrated low-noise power supply for SiPM biasing (20-85 V)
  • Supporting direct connection to CAEN DT5550 for signal digitization
  • Radiation Tolerant system
  • Ideal for high-resolution spectroscopy and calorimetry applications
  • User-replaceable plugin detector board to adapt to readout any SiPM
  • 64-channel kit available:
    • DT5550AFES
    • 2 x DT5550
    • SCI-Compiler license



The DT5550AFES is an analog frontend board designed for SiPM readout.

It is a multichannel preamplifier & shaper to be used in conjunction with one or two DT5550, to digitize the shaped signal. This system allows  to read out up to 64 independent channels, making the solution ideal to perform imaging and high-resolution spectroscopy with SiPM matrices and arrays.

Opposed to widely available ASIC-based solutions, the DT5550AFES is based on discrete preamplifying stages, so that it allows the direct sampling of the analog signal generated by the SiPM. Moreover, the large input dynamic range allows to use the board for particles calorimetry applications.

The analog frontend consists in independent transimpedance shaper amplifier (TIA), followed by a single-ended to fully-differential amplifier. Differential signals guarantee a better immunity to noise  and crosstalk between channels, and can be carried several meters away for digitization process, without any degradation.

A power supply module (CAEN A7585D) for SiPM biasing is mounted onboard, providing a common voltage in the range 20-85 V, with the possibility of individual channel adjustment. SiPM temperature is monitored using a digital temperature sensor. Thanks to this feature, a temperature feedback on the bias voltage is implemented.

The DT5550-AFES comes with a plugin board (called DT5550AFES Detector Board) to adapt to readout any SiPM matrix or array. It is a small square board which can be connected directly on the DT5550AFES input connector or adjusted in a different geometry with a micro-coaxial extension cable. The detector board exposes the 64 input/bias lines and can be so connected to another custom PCB hosting the SiPM. The Detector Board PCB project is available for free in order to help the user in the customization process.

The DT5550AFES, in conjunction with two CAEN DT5550 open-FPGA boards, realizes a complete 64-channels readout system for SiPMs, with programmable signal processing capabilities. The kit comes with SCI-Compiler, the CAEN user firmware generator and compiler for easy FPGA programming, and a ready-to-use readout software for waveform recording and spectra acquisition.


Developed in collaboration with Nuclear Instruments Srl

Technical Specifications


Form Factor Desktop OEM, with transparent plexiglass cover

Power Requirements
Power supply voltage: + 12 V
DC 2.1mm Power Socket connector

Analog Input

32/64 channels with trans-impedance based shaped amplifier (400 ns shaping time)

Up to 6000 photoelectrons input dynamic range

BIAS Voltage

Integrated low noise Power Supply (20-85 V) for SiPM

Analog Output

Shaped Differential Analog Output
Zdiff : 100 Ohm

2x 68-pin VHDCI connector
Suggested cable: SCSI-5 type

Supported connection to one or two DT5550 analog input


SCI-5550AFES Readout Software to manage the default firmware loaded on DT5550

Communication Interface

Managed by DT5550

Ordering Options

Code Description
WK5550AFES6A DT5550AFES - 64-CH Analog Front End and Read outSystem (2xDT5550 included) 
WA5550AFES6A 64-CH Analog Front End