High-speed readout solution for single-photon counting ASICs

作者：Kmon P^*; Szczygiel R; Maj P; Grybos P; Kleczek R

来源：Journal of Instrumentation, 2016, 11(02): C02057.

DOI：10.1088/1748-0221/11/02/C02057

• VLSI circuits
• X-ray detectors
• Pixelated detectors and associated VLSI electronics
• Front-end electronics for detector readout

We report on the analysis, simulations and measurements of both noise and high-count rate performance of a single photon counting integrated circuit called UFXC32k designed for hybrid pixel detectors for various applications in X-ray imaging. The dimensions of the UFCX32k designed in CMOS 130 nm technology are 9 : 63mm x 20 : 15 mm. The integrated circuit core is a matrix of 128 x 256 squared readout pixels with a pitch of 75 mu m. Each readout pixel contains a charge sensitive amplifier (CSA), a shaper, two discriminators and two 14-bit ripple counters. The UFXC32k was bump-bonded to a silicon pixel detector with the thickness of 320 mu m and characterized with the X-ray radiation source. The CSA feedback based on the Krummenacher circuit determines both the count rate performance and the noise of the readout front-end electronics. For the default setting of the CSA feedback, the measured front-end electronics dead time is 232 ns (paralyzable model) and the equivalent noise charge (ENC) is equal to 123 el. rms. For the high count rate setting of the CSA feedback, the dead time is only 101 ns and the ENC is equal to 163 el. rms.

• 出版日期2016-2