Design of Nupix-H2- Monolithic Active Pixel Detector Circuit

In nuclear and particle physics experiments, Monolithic Active Pixel Sensors (MAPS) are widely used in vertex and track detectors. To verify the multi-dimensional measurement requirements for MAPS in physics experiments on the High Intensity heavy-ion Accelerator Facility (HIAF), this paper designs a prototype MAPS named Nupix-H2- that can simultaneously measure the position, time, and energy. This prototype chip adopts the domestic 130 nm CMOS quad-well high-resistivity process. This chip has 1 row × 16 columns pixels, and the area of a single pixel is 22 μm × 22 μm. It uses the rolling shutter readout method to scan and read out each pixel's information at the frequency of 40 MHz. In each pixel, a charge-sensitive amplifier is used to measure energy information, and 16 pixels complete time measurement through a set of counters. The simulation results show that this pixel array's Equivalent Noise Charge (ENC) is less than 30 e⁻, the maximum Integral Non-Linearity (INL) of energy measurement is approximately 5%, and the time resolution reaches 25 ns.