A SPICE model of Si microstrip detectors

We have developed a SPICE model of an AC-coupled single-sided polysilicon-biased silicon microstrip detector and its associated read-out electronics. The detector SPICE model is based on a RC network, whose parameters have been determined by direct comparison with DC and AC measurements. The simulated interstrip and coupling impedance and phase angle are in good agreement with experimental results, up to a frequency of 1 MHz. The readout electronics is formed by the PreShaper 32 chip, consisting of a charge preamplifier followed by a shaping amplifier, which are the basis of its SPICE implementation. The propagation of an electrical signal, simulating the charge pulse of a ionizing particle, along strips and read-out electronics has been studied experimentally and compared to the SPICE results, in order to assess the quality of the model. A satisfactory agreement on the rising edge of the output signal has been found. Different read-out configurations have been investigated as well.