Browsing by Subject "front-end electronics"

Now showing 1 - 2 of 2

Access status: Open Access ,
Single Photon Counting X-ray Detector with 25 um Pixel Pitch
Gryboś, Paweł; Kłeczek, Rafał; Kmon, Piotr; Otfinowski, Piotr
Wydział Elektrotechniki, Automatyki, Informatyki i Inżynierii Biomedycznej
This paper presents the design and measurement results of a prototype integrated circuit called PIX25 for the readout hybrid pixel detectors operating in Single Photon Counting (SPC) mode. The IC is designed in the CMOS 40 nm process and its core is the matrix of 128 × 128 pixels. Usually, the pixel pitch in the SPC hybrid detector systems is in the range of 100 um down to 50 um. In the presented PIX25 IC the pixel pitch is only 25 um, which allows an increase in the position spatial resolution of the hybrid pixel detector and count rate per unit detector area beyond the state-of-the-art. Each pixel consists of a fast charge-sensitive amplifier with a detector leakage compensation circuit, a discriminator with a controlled threshold level, and 20-bit counters. To reduce the effects of pixel-to-pixel mismatch, each pixel contains independent blocks for offset and gain precise trimming. An important feature of the IC is its high reconfigurability. Each pixel can operate with the detector collecting holes or electrons. Thanks to the wide range of bias currents control the trade-off among power consumption, count rate, and noise performance can be obtained for a desired application. Additionally, the IC can be connected to sensors with a pixel pitch that is a multiplication of 25 um (e.g. 25 um, 50 um, 75 um, etc.). For operation with the detector pixel pitch of 50 um or higher any non-operating blocks/pixels in the readout matrix can be switched off, while their currents can be reused by working blocks/pixels only. Also each readout pixel can use up to 4 discriminators and 4 counters with different threshold settings.
Access status: Open Access ,
UFERI - Ultra-Fast Energy Resolved Imager for next generation synchrotron experiments
(2024) Andrä, Marie; Dawiec, Arkadiusz; Kłeczek, Rafał; Kmon, Piotr; Menneglier, Claude; Orsini, Fabienne; Otfinowski, Piotr; Gryboś, Paweł
Wydział Elektrotechniki, Automatyki, Informatyki i Inżynierii Biomedycznej
A new single photon-counting ASIC prototype called UFERI (Ultra-Fast Energy Resolved Imager) with a matrix of 42×42 pixels of 75 μm pitch is developed by the Detector Group of the SOLEIL synchrotron and the Microelectronics Group from AGH University of Krakow, in preparation for the upcoming upgrade of the SOLEIL synchrotron to a fourth-generation facility. The detector is dedicated to pseudo-Laue diffraction applications in intense, pink beams at photon energies between 5 to 30 keV. With its three thresholds and very small offset spread from pixel to pixel of about 1.1 mV, UFERI can discriminate three energy levels while its short dead time ensures a high count rate capability of up to 6 Mcounts/s/pix (10% count rate loss). To keep both, a low noise and a high count rate operation, a front-end amplifier’s feedback capacitor discharge technique is implemented on-chip, enabling high-speed chip operation with an Equivalent Noise Charge (ENC) of 86 e-rms. The UFERI chip can operate with detector signals of both polarities (holes and electrons) and consumes 42 μW/pixel. In this publication, we present a description of the ASIC’s architecture as well as characterisation results. The energy calibration, threshold dispersion, gain spread, as well as noise and count rate performance of the UFERI prototype are presented.