Speaker
Description
Large Area Picosecond Photodetectors (LAPPD) are a new generation of microchannel plate based photomultipliers being manufactured by Incom. These devices feature large sensitive area of 350 $cm^2$, high quantum efficiency ($\sim$20%), and tens of picosecond single photon level timing resolution. Initial devices use a stripline anode structure, allowing for high spatial resolution of 1-3 mm while minimizing the number of readout channels. These characteristics make LAPPD a very attractive option as a photodetector for collider experiments in High Energy Physics, such as future Charm-Tau Factories. In this report we present readout electronics which has been developed to be used with LAPPD devices. This electronics read out all channels of a single stripline-anode LAPPD. Waveform sampling up to 5GSPS is performed with the DRS4 switched-capacitor array ASIC. All DRS4 channels are digitized in parallel with two 32-channel ADCs. An on-board FPGA coordinates digitization and readout of waveforms, and could further be expanded to include some waveform processing. Data packages built in the FPGA are sent to a DAQ system via optical fiber, with a baseline Gigabit Ethernet interface implemented entirely on the FPGA. The electronics has different triggering options: self-triggering using DRS4 transparent mode and external triggering, making event control very flexible. Further flexibility is enhanced with embedded software for an on-FPGA soft-core processor, as well as DAQ readout and control software. This open-source ecosystem is being developed to provide full control of the device operation and an easy way to integrate it to any environment. In the report we describe the status of the electronics development along with its firmware and readout software.
