A CMOS 0.13μm read-out front-end for Triple-Gas-Electron-Multiplier detectors

In this paper a dedicated integrated front-end for the Triple-GEM (Gas Electron Multiplier) detector is presented. The design has been realized in 0.13 μm CMOS technology. This system aims to improve performance with respect to the state-of-the-art on these types of detectors, regarding adaptability, portability, power consumption and on-chip data processing. The front-end is composed by 8-input-channels. Each channel performs the charge-vs-time conversion, and then the signal is definitively converted into digital domain. For this aim a Charge-Sensitive Preamplifier (CSP), and a Charge-to-Time Converter (CTC) are implemented. An automatic on-chip calibration circuit is also included, in order to compensate CMOS technological process/temperature variations. The system is able to manage a 15 pF detector capacitance. The maximum count rate is 4·10⁶ counts-per-second (cps) and the power consumption is 3.8 mW/ch. The Equivalent Noise Charge (ENC) is 418 e^-. The front-end compares favorably with the state-of-the-art.