Development and Current Status of 256-Pixel SiPM Based Imaging Camera for Cherenkov Telescope

A 256-pixel imaging camera for a 4-meter class Imaging Atmospheric Cherenkov Telescope (IACT) is being developed in-house by TIFR. The camera uses a 4 \(\times \) 4 array of SiPMs as a photodetector for each pixel. The pixel signals are pre-conditioned in the front-end electronics modules and fed to back-end modules. The front-end electronics comprise the modules for pre-amplification and biasing of pixel sensors. The back-end electronics of the camera continuously samples the pre-amplified pixel signal @ 1 GSPS using a switched capacitor array of 1024 ns sampling depth and records the pulse profile after receiving a valid final trigger signal. The back-end electronics also handle the tasks such as generating pre-triggers & a final trigger to digitize the pixel signals, data concentration, internal calibration of the hardware, recording the event and monitoring data packets to the PC in the control room etc. Both front-end and back-end modules of the camera follow a modular design concept. The camera back-end has three types of modules viz., 16 Cluster Digitizer Modules (CDMs), 1 Data Concentrator Module (DCM) and 1 Control & Trigger Module (CTM). All the back-end modules are connected to each other using a backplane PCB and accommodated in a customized VME crate. The camera operation is managed with the help of a stack of firmware and software programs developed indigenously. The design, development and current status of the camera will be presented in this talk.