Development of a fully integrated readout system for high count rate position-sensitive measurements of X-rays using silicon strip detectors

Abstract

The paper describes the development of a multichannel readout system for X-ray measurements using silicon strip detectors. The system comprises two application-specific integrated circuits (ASICs), a front-end chip, and a digital data storage chip. In the front-end ASIC, a binary readout scheme is employed. The binary data are stored in the asynchronous counters and read out serially at the end of the measurement sequence. The front-end circuit is designed such that it can work with direct current coupled detectors with a leakage current up to few nanoamperes. The size of the input device is optimized for a detector capacitance in the range from 2-5 pF per strip. An equivalent noise charge of 110 electrons rms has been achieved for the total strip capacitance of 2.5 pF at the peaking time of 1 /spl mu/s. Low noise performance and high counting-rate capability have been demonstrated by measurements of X-ray spectra.