Beam test performance of the APV5 chip

Abstract The performance of the latest prototype of the radiation hard front end chip to be used by the CMS collaboration for analogue readout of the microstrip tracker has been evaluated with a silicon microstrip detector in a beam at CERN. The circuit, developed by the RD20 collaboration, consists of 128 channels of amplifier, pipeline memory, analogue signal processor and a serial multiplexer. As a result of these studies improvements in the circuit design have been devised which will be implemented in the next version.