A charge sensitive amplifier (CSA) is a primary module of the front-end electronics of many types of silicon detectors, as well as most radiation detection systems. High gain, low input noise, and stability are the primary features of a typical CSA circuit to accomplish an amplified susceptible input charge (current) for added processing.
The CSA discussed in this article is a liquid argon ASIC (LArASIC) with a 16-channel front end, designed in a 180-nm CMOS process. This device was designed for full operation in a cryogenic temperature range spanning 77 to 89 Kelvin. This ASIC has 16 channels of charge amplifiers and shapers with a programmable gain and filter time constant that allows for measurement of weak charge signals from liquid argon Time Protection Chamber (LArTPC) sensing wires and PCB strips.