Beam test performance of the APV5 chip

Performance of a cluster of multi-anode photomultipliers equipped with lenses for use in a prototype RICH detector

“…The output signal channels in the back plane of the bleeder board were coupled to the front-end boards via kapton cables. Each frontend board multiplexed the analogue signals from one or two MaPMTs and was the carrier for the front-end ASIC (Application-Specific Integrated Circuit), the Analogue Pipeline Voltage (APVm) [8,9,10]. The APVm shaped, amplified, buffered and multiplexed the input signals.…”

“…The front-end board also carried further components to perform three additional functions: (i) buffers to drive the output data signals through 10 m of cable to the data acquisition system outside the experimental area, (ii) components to set unique addresses for each frontend ASIC, so that the control voltages and currents could be set individually via an I 2 C control link and (iii) a switch to interrupt the power and thus reset the APVm. The APVm [10] is one of the APV series [8,9] of radiation-hard front-end ASICs which have been designed for the readout of the CMS inner detector [12]. The APVm has been fabricated using the Harris AVLSIRA bulk CMOS process [13].…”

“…The APVm has been fabricated using the Harris AVLSIRA bulk CMOS process [13]. These ASICs have been previously used in a beam environment for the readout of silicon-strip detectors [8].…”

“…In particular, the 1:128 multiplexing of the analogue signals at 20 MHz precluded operation at the first-level trigger rate of 1 MHz [14] and a signal return-to-zero within 25 ns was only possible in the de-convolution mode of APVm operation [8]. This requires 3 consecutive samples for the algorithm, and therefore prevents triggering on consecutive events.…”

“…This was established by the simultaneous pulsed emission of light from LEDs positioned at the beam entrance to the RICH prototype vessel and within one of the scintillators used in the trigger 8 . This imitated the beam conditions ofČerenkov radiation in the RICH vessel and a charged particle causing scintillation light in the beam counters respectively.…”