A 25 mW smart CMOS wind sensor with corner heaters

A smart CMOS thermal wind sensor has been optimized for commercial use. Optimizing the sensor chip´s thermal design resulted in better area efficiency and improved thermal dynamics with respect to prior work. The latter simplifies the off-chip decimation of the sensor´s bitstream outputs. Moreover, by realizing more logic on-chip, the number of bond wires has been reduced by 33%, to 8, thus reducing manufacturing costs. Fabricated in a standard 0.7μm CMOS process, the sensor chip occupies 4×4mm² and consumes 25mW of heating power, while achieving an inaccuracy of ±6% (speed) and ±2° (direction), for wind speeds between 4 and 25m/s.