Performance Testing of a Two-dimensions Vernier TDC ASIC

TDCs (Time-to-digital Converters) are widely applied in nuclear and particle physics experiments. With the development of high energy physics experiments, higher and higher TDC precision is required. A Two-Dimensions Vernier based TDC prototype ASIC based on 180 nm CMOS technology was designed in State Key Laboratory of Particle Detection and Electronics, which features a high resolution. A test platform was set up and a test module was designed for the TDC performance evaluation. The test module can receive multiple TDC chips’ data and transfer them with a high speed, and to cope with the nonlinear problem of high-precision TDCs, the hardware nonlinear calibration method is adopted to greatly improve the accuracy of TDCs. In order to facilitate the massive testing in the future, an automatic test software system was also developed which can automatically perform time interval scan and data collection, improving test efficiency. Test results indicate that this TDC achieves a time resolution of better than 10 ps RMS with a bin size of around 22.7 ps and a measurement dynamic range of up to 2.5 µs.