Design and Development of Advanced Low Power Hybrid Acquisition (ALPHA) ASIC for Antarctic Demonstrator for the Advanced Particle-astrophysics Telescope (ADAPT)

This paper discusses the design and development of an Application Specific Integrated Circuit (ASIC) named ALPHA for the Advanced Particle-astrophysics Telescope (APT) sensor elements readout. ALPHA is responsible for scintillating fiber-trackers, and imaging calorimeters to measure gamma-rays and other cosmic-rays. The readout process includes analog sampling, sample conversion with an Analog to Digital Converter (ADC), output-data packet transmission, and collection to Field Programmable Gate Arrays (FPGA). Novel in this architecture is the daisy-chaining of the readout, as well as sharing of clocking resources, all to reduce power. For the readout sequence and the data transmission sequence to work adequately, two data paths, two token paths, and two sampling banks are featured. Two paths can bypass any defective ALPHAs, and a token is used for collision avoidance in the data transmission path. The token and data packet transmit in opposite direction from each other. A token starts from the FPGA initially and loops around the daisy chain until the ADAPT ends its mission. On the other hand, the data packets start from each ALPHA. When a token reaches an ALPHA that has a data packet that is waiting to shift out, the data packet starts shifting through the data path toward the FPGA for collection. The ALPHA was manufactured by TSMC and the functionality of the digital block was tested. In conclusion, the ALPHA functions as expected.