A CMOS wind speed to frequency converter with calibration circuits

In this paper, a CMOS wind speed to frequency converter with calibration circuits is newly proposed. A calibration technique is proposed in this work. Another innovation is that the outputs of the proposed chip are directly digitized, they could be easily sent over a wide range of transmission media, such as PSN, radio, optical, IR, ultrasonic, and etc. Before performing the proposed calibration circuits, the maximum linear error is 57.3%. After calibration, the maximum linear error is reduced to 2.4%.The wind speed range is 2.6 to 3.1 m/s, and the corresponding output frequency range is 78.1 kHz to 455 kHz. The chip area is 1.08 × 1.08 mm². The proposed chip is suitable for devices of measuring wind speed.