Sensor for gas analysis based on thermal conductivity, specific heat capacity and thermal diffusivity

Kliche, K.; Billat, S.; Hedrich, F.; Ziegler, Christoph; Zengerle, Roland

doi:10.1109/memsys.2011.5734644

Cited by 16 publications

(16 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Rather than measuring the steady-state temperature rise of a heated wire, an alternative method is to characterize its thermal time constant τ th , which is the product of its thermal resistance to ambient (R th ) and its thermal capacitance (C th ) [15]- [17]. When the wire is driven with a current I d pulsed at a frequency f drive , and is thus periodically heated, its temperature transients are delayed relative to the driving pulses.…”

Section: B Time-domain Thermal-conductivity Sensingmentioning

confidence: 99%

“…To measure TC accurately, a steady-state approach is usually employed, in which the power dissipation of a transducer is maintained at a well-defined level, and the resulting temperature rise is measured [15]- [17]. To relax the requirements on the stability of the transducer's power dissipation, Cai et al [14] propose a ratiometric approach, in which the temperature and power dissipation of CO 2 -sensing and reference transducers are measured, and then used to calculate a CO 2 -dependent TC ratio.…”

Section: Introductionmentioning

confidence: 99%

“…As an alternative to a steady-state measurement, TC can also be derived from a transient measurement of the transducer's thermal time constant τ th , i.e., the product of its thermal capacitance (C th ) and its thermal resistance to ambient (R th ), since this also depends on the TC of the surrounding air [15]- [17]. This approach has the important advantage that the measurement of τ th relies on a time reference, and hence the absolute temperature and power levels do not need to be accurately stabilized or measured.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

A Phase-Domain Readout Circuit for a CMOS-Compatible Hot-Wire CO₂Sensor

Cai¹,

Veldhoven²,

Suy³

et al. 2018

IEEE J. Solid-State Circuits

View full text Add to dashboard Cite

Section: B Time-domain Thermal-conductivity Sensingmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

A Phase-Domain Readout Circuit for a CMOS-Compatible Hot-Wire CO₂Sensor

Cai¹,

Veldhoven²,

Suy³

et al. 2018

IEEE J. Solid-State Circuits

View full text Add to dashboard Cite

“…It is also quite common in Micro-Electro-Mechanical-Systems (MEMS) to have heat generation/dissipation in fast transient conditions. [42][43][44][45][46][47][48] Some actuators are thermally driven in pulsed mode, such as the membrane of one kind of micro-pumps. Micro-sensors, as well, which are made small to capture fast dynamic effects may also experience transient thermal effects.…”

Section: Industrial Applications Of Time-dependent Characterizationmentioning

confidence: 99%

Techniques to Create Compact Thermal Models — Dynamic Problems

Lasance

Sabry

Bar‐Cohen

2014

Encyclopedia of Thermal Packaging

View full text Add to dashboard Cite

Many business objectives related to performance, functionality, reliability and safety are affected by temperature. Most reliability protocols at present consider the steady state temperature the only stressor affecting reliability. Consequently, system designers often use temperature reduction as the primary means to improve reliability. However, is the steady state temperature indeed the dominant parameter? There is ample evidence that temperature gradients in space and time are far more important than the absolute temperature (see e.g. Lall et al., 1 Pecht, 2 Parry et al. 3 ). Section 7.2 will discuss a number of application fields for which time-dependent temperature measurements or predictions become increasingly important.Although a growing awareness of the importance of dynamic thermal effects has been lately noticed, the large majority of electronic system designers still believe that time constants of thermal effects are huge compared to those of electronic systems and hence, steady thermal analysis should be sufficient. This last statement is not always true. In fact, as will be proven both qualitatively and quantitatively in this chapter, there is an infinite set of thermal time constants. Some of them are quite comparable to those of electronic phenomena; others are quite larger. Whether or not should one consider dynamic thermal effects, depends on which problem is addressed.This chapter starts with a quick overview of cases where dynamic effects may be important. Then, fundamental aspects of transient modeling will first be introduced for a simple transient one-dimensional problem in order to gain physical understanding about basic notions involved. This will be followed by a well-known application: the structure function. It will then be generalized to fixed profile 3D problems. Next, a review of methods is proposed for constructing Dynamic Compact Thermal Models (DCTM). A general theoretical framework for transient problems with variable profiles will follow based on the same ideas given above for static problems. Some extensions will be briefly addressed in the last section.

show abstract

“…AC driven calorimetric flow sensors are also used to characterize the physical properties of the fluid only when the flow conditions were already established [3,[8][9][10], i.e., the flow speed is known. Frequency analysis of thermal flow sensor does not represent any novelty itself [3,8,9,11,12].…”

Section: Introductionmentioning

confidence: 99%

Simulation of the frequency response of a thermal flow sensor in gaseous media

Romero

Urban

2012

2012 13th International Thermal, Mechanical and Multi-Physics Simulation and Experiments in Microelectronics and Microsystems

View full text Add to dashboard Cite

The frequency response of a calorimetric flow sensor is simulated for many selected gases. The effect of selected thermal properties of the gas on the frequency response is analyzed. The thermal conductivity is found to be the dominant parameter on the cut-off frequency of the sensor. This influence seems to be linear in nature. Moreover, the influence of the flow speed on the frequency response is also found to be much smaller than that of the thermal conductivity.

show abstract

Sensor for gas analysis based on thermal conductivity, specific heat capacity and thermal diffusivity

Cited by 16 publications

References 4 publications

A Phase-Domain Readout Circuit for a CMOS-Compatible Hot-Wire CO₂Sensor

A Phase-Domain Readout Circuit for a CMOS-Compatible Hot-Wire CO₂Sensor

Techniques to Create Compact Thermal Models — Dynamic Problems

Simulation of the frequency response of a thermal flow sensor in gaseous media

Contact Info

Product

Resources

About

Sensor for gas analysis based on thermal conductivity, specific heat capacity and thermal diffusivity

Cited by 16 publications

References 4 publications

A Phase-Domain Readout Circuit for a CMOS-Compatible Hot-Wire CO2Sensor

A Phase-Domain Readout Circuit for a CMOS-Compatible Hot-Wire CO2Sensor

Techniques to Create Compact Thermal Models — Dynamic Problems

Simulation of the frequency response of a thermal flow sensor in gaseous media

Contact Info

Product

Resources

About

A Phase-Domain Readout Circuit for a CMOS-Compatible Hot-Wire CO₂Sensor

A Phase-Domain Readout Circuit for a CMOS-Compatible Hot-Wire CO₂Sensor