All-digital Linearity Enhancement Technique for Time-domain Smart Temperature Sensors
Chun-Chi Cen, Chao‐Lieh Chen, Yi Lin · Procedia Engineering · 2014
An all-digital linearity enhancement technique for time-domain CMOS smart temperature sensors was implemented on a Xilinx XC3S200AN FPGA (Field Programmable Gate Array) to improve the sensors accuracy. With a calibration circuit, the effect of process variations on the sensor outputs is eliminated effectively. Then, the linearity enhancement circuit is proposed to linearizethe outputs to attain the new ones with linearity enhancement. The maximal inaccuracy is reduced from 3 ̊C to 1.5 ̊C after one- point calibration in a range from -20 to 100 ̊C. The experimental result validates that the proposed technique for time-domain sensors functions successfully.