IDeF-X ECLAIRs: A CMOS ASIC for the Readout of CdTe and CdZnTe Detectors for High Resolution Spectroscopy

The very last member of the IDeF-X ASIC family is presented: IDeF-X ECLAIRs is a 32-channel front end ASIC designed for the readout of Cadmium Telluride (CdTe) and Cadmium Zinc Telluride (CdZnTe) Detectors. Thanks to its noise performance (Equivalent Noise Charge floor of 33 ${\rm e}^{-}\ {\rm rms}$) and to its radiation hardened design (Single Event Latchup Linear Energy Transfer threshold of 56 ${\rm MeV}.{\rm cm}^{2}.{\rm mg}^{-1}$), the chip is well suited for soft X-rays energy discrimination and high energy resolution, “space proof,” hard X-ray spectroscopy. We measured an energy low threshold of less than 4 keV with a 10 pF input capacitor and a minimal reachable sensitivity of the Equivalent Noise Charge (ENC) to input capacitance of less than 7 ${\rm e}^{-}/{\rm pF}$ obtained with a 6 $\mu{\rm s}$ peak time. IDeF-X ECLAIRs will be used for the readout of 6400 CdTe Schottky monopixel detectors of the 2D coded mask imaging telescope ECLAIRs aboard the SVOM satellite [1]. IDeF-X ECLAIRs (or IDeF-X V2) has also been designed for the readout of a pixelated CdTe detector in the miniature spectro-imager prototype Caliste 256 [2] that is currently foreseen for the high energy detector module of the Simbol-X mission [3].