Krummenacher feedback analysis for high-count-rate semiconductor pixel detector readout

The Krummenacher feedback circuit is a well know and often used in charge sensitive amplifiers (CSA) connected to DC-coupled semiconductor detectors. The circuit provides in a very simple structure dual functionality: continuous reset and detector leakage current compensation. In spite of the simplicity the characterization of the circuit for high speed applications is not very straightforward. This article presents an analysis of the feedback circuit based on 90 nm CMOS and technology and targeted at high-count-rate semiconductor hybrid pixel detector applications realized in submicron or 3D technologies.