A Novel Low Cost Lead-frame Air Flow Anemometer

A novel lead-frame air flow sensor is presented. It is a compact low cost solution which allows easy PCB mounting and adaptation to standard size small air pipes. Based on the hot-wire principle, it has been optimized to provide a short time response and high thermal isolation between hot and cold points, while keeping low cost packaging. For optimum time response, power efficiency and robustness in front of noise the sensor is operated in closed-loop thermal Σ-Δ conversion which provides digital read-out with a simple circuit topology.

[1]  Manuel Domínguez Pumar,et al.  Bounding of thermal /spl Sigma/-/spl Delta/ modulators output for sensors , 1999, ISCAS'99. Proceedings of the 1999 IEEE International Symposium on Circuits and Systems VLSI (Cat. No.99CH36349).

[2]  Angel Rodriguez,et al.  A conduction-convection design for liquid flow sensing , 1998 .

[3]  Johan H. Huijsing,et al.  Design of integrated thermal flow sensors using thermal sigma—delta modulation , 1996 .

[4]  Angel Rodriguez,et al.  Flow measurement hits home , 1997 .

[5]  Johan H. Huijsing,et al.  Design of thermal sigma-delta modulators for smart thermal sensors , 1995, Proceedings of ISCAS'95 - International Symposium on Circuits and Systems.

[6]  R. Schreier,et al.  Delta-sigma data converters : theory, design, and simulation , 1997 .

[7]  Richard Bayford,et al.  Design and fabrication of single-chip intelligent silicon thermal flow sensors in standard CMOS technology , 1996 .

[8]  G. Temes.  Delta-sigma data converters , 1994 .

[9]  Leon O. Chua,et al.  The effect of integrator leak in Sigma - Delta modulation , 1991 .

[10]  M. Elwenspoek,et al.  A new class of thermal flow sensors using /spl Delta/T=0 as a control signal , 2000, Proceedings IEEE Thirteenth Annual International Conference on Micro Electro Mechanical Systems (Cat. No.00CH36308).