Speakers
Description
Waveform digitizers with a Wilkinson ADC are widely used in particle physics, but they are designed in proprietary processes: design files cannot be shared without non-disclosure agreements, and every iteration is costly. We are building a waveform digitizer ASIC with the IRSX architecture as its model, using only an open process design kit (GF180MCU) and open-source design tools. The entire design is public, fabrication uses low-cost community shuttles, and the full chip is rebuilt and verified every night from the repository. This software-like flow invites outside review and collaboration; AI tools assist within it, under human review. The first chip is a deliberately small design that exercises the whole flow: one channel with four sampling cells, each with a MIM hold capacitor and its own comparator, and 8-bit Wilkinson conversion of all cells in parallel. Bottom-plate sampling makes the switch charge injection independent of the signal and lets every comparator decide at a fixed voltage. We present the design and simulation results, including transient-noise simulation with open-source tools showing comparator noise well below one LSB, the digital-on-top integration of the analog blocks, and the staged plan toward deeper memory, more channels, and higher resolution.