The semiconductor pixel detector Timepix contains an array of 256 × 256 square pixels with pitch 55 µm. In addition to high spatial granularity the single quantum counting detector Timepix can provide also energy or time information in each pixel. This device is a powerful tool for radiation and particle detection, imaging and tracking. A new readout interface for silicon pixel detectors of the Medipix family has been developed in our group in order to provide a higher frame rate and enhanced flexibility of operation. The interface consists of a field programmable gate array, a USB 2.0 interface chip, DAC, ADC and a circuit which generates bias voltage for the sensor. The main control system is placed in the FPGA circuit which fully controls the Timepix device. This approach offers an easy way how to include new functionality and extended operation. The interface for Timepix supports all operation modes of the detector (counting, TOT, timing). The FITPix is a successor of the USB 1.22 Interface and the electronic readout is built with the latest available components, which allows achieving up to 90 frames per second with a single detector. The frame rate is about 20 times faster compared to the previous system while it maintains all same capabilities supported. In addition FITPix newly enables an adjustable clock frequency and hardware triggering which is a useful tool when there is the need for synchronized operation of multiple devices. Three modes of hardware trigger have been implemented: hardware trigger which starts the measurement, hardware trigger which terminates the measurement and hardware trigger which controls measurement fully. The entire system is fully powered through the USB bus. FITPix supports also readout from several detectors in chain in which case just an external power source is required. FITPix is a fully flexible device and the user needs no other equipment. FITPix combines high performance and mobility and it opens new fields of applications. The current version of the FITPix interface has dimension 45 mm × 60 mm.

In the presented work, the parameters of a new MAPD-3NM-II photodiode with buried pixel structure manufactured in cooperation with Zecotek Company are investigated. The photon detection efficiency, gain, capacitance and gamma-ray detection performance of photodiodes are studied. The SPECTRIG MAPD is used to measure the parameters of the MAPD-3NM-II and scintillation detector based on it. The obtained results show that the newly developed MAPD-3NM-II photodiode outperforms its counterparts in most parameters and it can be successfully applied in space application, medicine, high-energy physics and security.

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This paper presented a new detector module consisting of a micropixel avalanche photodiode (MAPD-3NM), LaBr 3 :Ce scintillator, and a compact read-out interface system for detecting gamma-rays in a wide energy range. The MAPD array (4 × 4 channels) was assembled using a single MAPD-3NM characterized by its high photon detection efficiency (∼25%), pixel density (10 000 pixels/mm 2 ), low operation voltage (74.5 V), and low dark current. An active area of a single MAPD-3NM was 3.7 × 3.7 mm 2 , while this value was 17 × 17 mm 2 for the assembled array with pixel density of 2190 000. The size of the tested LaBr 3 :Ce scintillator was 15 × 15 × 15 mm 3 . According to the characteristics of the detector module, a compact read-out interface device (SPECTRIG MAPD) was developed. SPECTRIG MAPD was designed as a miniature device with low power consumption, which continues to provide a wide spectrum of functions needed for measurement and test silicon photomultipliers (SiPM) and scintillation detectors on their basis. The various experiments were implemented to test the detection performance of a detector module to gamma radiation in the range from 30 keV to 4400 keV.

In this study, we present the gamma-ray detection performance of LYSO, YSO(Ce) and BGO scintillators read out by a 9 ch. micropixel avalanche photodiode (MAPD) array with a high pixel density (PD) and photon detection efficiency (PDE). The array with an active area of 11.5 × 11.5 mm 2 was assembled using single MAPDs with an active area of 3.7 × 3.7 mm 2 . It had a single output signal and was developed for gamma spectroscopy. Breakdown voltage measurements were carried out for each channel, as a result of which the optimal operating voltage for the array was found. The linearity range and energy resolution for each crystal were determined in the energy range from 30 to 1770 keV. The high pixel density of the array allowed to achieve good linearity in the studied energy range.