A low-power CMOS 0.13 µm Charge-Sensitive Preamplifier for GEM detectors

In this paper a Charge-Sensitive Preamplifier (CSP) for GEM (Gas Electron Multiplier) detectors readout is presented. The CSP is responsible for signal acquisition and the conversion of the input charge into a voltage signal. The design has been realized in 0.13 μm CMOS technology. It has been demonstrated through a detailed analysis that this is the best CMOS technology to be used in this case, as regards power consumption, intrinsic gain, noise and radiation hardness. The aim is to reduce the power consumption while maintaining other performance at the state-of-the-art. The preamplifier is composed by a three-stage nested Miller Operational Amplifier, with a feed-forward compensation. The system is able to manage a 15 pF detector capacitance. The global power consumption is 1.1 mW and the Equivalent Noise Charge is 418 e-.