Smart sensor design: The art of compensation and cancellation

Smart sensors are systems in which sensors and dedicated interface electronics are integrated on the same chip, or at least in the same package. Due to the low-level analog output of typical sensors, designing interface electronics that "does no harm," i.e. does not impair sensor performance, is quite challenging, especially in today's mainstream CMOS technology, whose inherent precision is limited by I/f noise and component mismatch. However, since most sensors are quite slow compared to transistors, dynamic techniques can often be used to trade speed or bandwidth for higher precision. Examples of such techniques are auto zeroing, chopping, dynamic element matching, switched-capacitor filtering and sigma-delta modulation. This paper describes the use of such dynamic techniques in the design and realization of state-of-the-art smart CMOS sensors for the measurement of temperature, wind velocity and magnetic field.

[1]  J. Huijsing,et al.  A CMOS smart temperature sensor with a 3σ inaccuracy of ±0.1°C from -55°C to 125°C , 2005, IEEE J. Solid State Circuits.

[2]  Anton Bakker Smart Sensor Interfaces: An Introduction , 2004 .

[3]  Kofi A. A. Makinwa,et al.  A CMOS smart temperature sensor with a 3σ inaccuracy of ±0.1°C from -55°C to 125°C , 2005, IEEE J. Solid State Circuits.

[4]  Farrokh Ayazi,et al.  Micromachined inertial sensors , 1998, Proc. IEEE.

[5]  J.H. Huijsing,et al.  A smart CMOS wind sensor , 2002, 2002 IEEE International Solid-State Circuits Conference. Digest of Technical Papers (Cat. No.02CH37315).

[6]  M.A.P. Pertijs,et al.  Precision temperature measurement using CMOS substrate pnp transistors , 2004, IEEE Sensors Journal.

[7]  Gabor C. Temes,et al.  Circuit techniques for reducing the effects of op-amp imperfections: autozeroing, correlated double sampling, and chopper stabilization , 1996, Proc. IEEE.

[8]  J.H. Huijsing,et al.  A sigma-delta modulator with bitstream-controlled dynamic element matching , 2004, Proceedings of the 30th European Solid-State Circuits Conference.

[9]  J.H. Huijsing,et al.  A 2nd order thermal sigma-delta modulator for flow sensing , 2005, Italian National Conference on Sensors.

[10]  Kofi A. A. Makinwa,et al.  A smart wind sensor using thermal sigma-delta modulation techniques , 2002 .

[11]  Johan H. Huijsing,et al.  An electronic wind meter based on a silicon flow sensor , 1990 .

[12]  Kofi A. A. Makinwa,et al.  Flow sensing with thermal sigma-delta modulators , 2004 .

[13]  G.C.M. Meijer,et al.  Temperature sensors and voltage references implemented in CMOS technology , 2001, IEEE Sensors Journal.

[14]  P.J.A. Munter Spinning-current method for offset reduction in silicon Hall plates , 1992 .

[15]  J.H. Huijsing,et al.  An IF-to-Baseband $\Sigma \Delta$ Modulator for AM/FM/IBOC Radio Receivers With a 118 dB Dynamic Range , 2007, IEEE Journal of Solid-State Circuits.

[16]  Christoph Hagleitner,et al.  CMOS single-chip gas detection system comprising capacitive, calorimetric and mass-sensitive microsensors , 2002, IEEE J. Solid State Circuits.

[17]  G.C. Temes,et al.  A low-power 22-bit incremental ADC , 2006, IEEE Journal of Solid-State Circuits.

[18]  E. van Kampen,et al.  Low-cost epoxy packaging of CMOS Hall-effect compasses , 2005, IEEE Sensors, 2005..

[19]  Johan H. Huijsing,et al.  Precision Temperature Sensors in CMOS Technology , 2006 .

[20]  J.H. Huijsing,et al.  A fully integrated CMOS Hall sensor with a 3.65 /spl mu/T 3/spl sigma/ offset for compass applications , 2005, ISSCC. 2005 IEEE International Digest of Technical Papers. Solid-State Circuits Conference, 2005..

[21]  M. Geske,et al.  The Hall Effect in Silicon Circuits , 1980 .

[22]  B. W. Oudheusden,et al.  Silicon thermal flow sensor with a two-dimensional direction sensitivity , 1990 .

[23]  Timothy Denison,et al.  A 2.2/spl mu/W 94nV//spl radic/Hz, Chopper-Stabilized Instrumentation Amplifier for EEG Detection in Chronic Implants , 2007, 2007 IEEE International Solid-State Circuits Conference. Digest of Technical Papers.

[24]  Kofi A. A. Makinwa,et al.  A wind-sensor interface using thermal sigma delta modulation techniques , 2001 .

[25]  Kofi A. A. Makinwa,et al.  Interface Electronics for a CMOS Electrothermal Frequency-Locked-Loop , 2008, IEEE J. Solid State Circuits.

[26]  Kofi A. A. Makinwa,et al.  Interface electronics for a CMOS electrothermal frequency-locked-loop , 2007, ESSCIRC 2007 - 33rd European Solid-State Circuits Conference.

[27]  A. Bakker,et al.  A CMOS nested-chopper instrumentation amplifier with 100-nV offset , 2000, IEEE Journal of Solid-State Circuits.

[28]  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).