I-Spector Plus

Intelligent Silicon Photomultiplier Tube with Digital MCA


The i-Spector Digital is a fully-integrated  Gamma Spectrometer designed to operate as a complete radiation detection system, with integrated MCA and optional wireless connectivity. This compact unit is based on a SiPM area (18×18, 24×24 or 30×30 mm2) and hosts a preamplifier stage, an integrated power supply for SiPM biasing with temperature feedback loop, a shaper and a full-featured MCA based on 80 MSps, 12-bit ADC and digital charge integration algorithm. The i-Spector Digital can be controlled through Ethernet and it provides as output an analog amplified signal and a 4k channels energy spectrum calculated onboard.

i-Spector is a solution dedicated to those users that need the versatility of a full compact single photodetection system for spectroscopy applications. Its profile makes it ideal for many portable applications where size, weight and power consumption are important constraints. The embedded MCA can be easily set up and operates with essentially no configuration.

i-Spector LoRa integrates an additional radiocommunication interface which is ready to connect to LoRaWAN networks for IoT and environmental monitoring applications. A cloud server (Rad Cloud) allows to collect data from multiple i-Spector and display them on maps or interactive tables.

The Web-based interface allows the user to configure and monitor the device, with the possibility to access the spectrum, process it online, perform energy calibration and peaks gaussian fitting. Multiple i-Spector tubes can be connected and controlled from a single PC. The API interface allows to control multiple devices using very simple http requests and JSON vectors.

  • All-in-one detector, electronics and MCA for Gamma Spectroscopy
  • Based on a SiPM area up to nearly 1.5 inch2
  • 20-80 V Integrated High Voltage for SiPM biasing
  • OEM electronics or detector assembly
  • Assembly with CsI scintillator:
    • 18x18x30 mm3
    • 24x24x30 mm(approx. 1x1x1.2 inch3)
    • 30x30x38 mm(approx. 1.2×1.2x 1.5 inch3)
  • Other assembly option available on request: NaI, BGO, LYSO, LaBr3 or any other compatible scintillator
  • Demountable mechanics to easily change crystal
  • Ethernet and optional LoRa connectivity
  • Rad Cloud software for multiple detector networking (FREE TRIAL)
  • i-Spector LoRa, with LoRa radioantenna  for IoT and environmental applications
  • Web-based interface with spectrum analysis tools
  • Compact form factor
    • Ø 60 mm, h 90 mm (OEM)
    • Ø 60 mm, h 135 mm (ASSEMBLY)


The homepage show the status of the HV generator (voltage, current, enable and protection) and the temperature on the detector. User can power on/off the HV and set the output voltage. On the left menu it is possible to access to the secondaries pages:

  • Monitor: home page with HV and detector status
  • vHistory: download last hour of data (votage, current, and temperature) from the microcontroller and then accumulate data forever until the page is open
  • Spectrum: Allow to access to the spectrum data, perform online analysys (area under peak, fitting, setup alarms) and download the spectrum data
  • Settings: advanced settings for the HV controller like temperature compensation, protection and HV status on power on
  • Configuration: ethernet configuration

The NIPM13 module has an internal circular buffer memory of an hour where it stores voltage, current and temperature of the sensor. The history page download this information that are always sampled even if the history page is not opened. When the user open this page last hour of data is immediatly downloaded and then every second the whole data set is updated. If the page is opened there isn’t a real limit to the number of points that the plots will show. It depends only by the ram memory of the computer.

In the settings page user can program the following parameters:

  • HV ON/OFF: switch on/off the HV power supply using the programmed ramp
  • HV Voltage: Set the desidered HV voltage
  • HV mode: Select between Digital and Temperature Compensate. When Temperature Compensate is selected, the SiPM HV voltage will be automatically adjoust to correct the temperature drift changing.
  • Compliance (Vout): set the maximum Vout. If the ADC measure an higher voltage, the HV setpoint will be adjoust to limit the output voltage
  • Over current protection: If the output current overcomes this limit the HV output is immediatly switched of without any ramp. This is not a current limitation but a protection system to limit the current in case of short circuit or if the SiPM matrix is accidentally exposed to ambient light while it is powered on
  • Ramp Speed: Ramp up/down applied to the HV voltage to limit the derivate of the HV to do not damage AC coupled ASIC IC
  • SiPM temperature Coefficient This coefficient is applied to the HV output voltage reducing or increasing the nominal HV voltage by the following formula Vout = Vset – Tcoef*(T-25)
  • For example, if Vset = 50v, Tcoef =50mV/°C and T=35°C Vout will be corrected of 500mV. So the Vout = 49.5v
  • HV Output on startup: select the status of the HV when the power is applied to the NIPM13 device. If user wants to operate without ethernet connection to the device, it is possible to set HV output voltage and select Power ON in the HV Output on startup.

This product is sold with CAEN