混合信號溫度控制電路[外文翻譯].doc
混合信號溫度控制電路[外文翻譯],mixed-signal temperature control circuit1 introductionnow the gas sensors are widely used, such as environmental monitoring, air quality control...
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此文檔由會員 huangbinbest 發(fā)布混合信號溫度控制電路[外文翻譯]
mixed-signal temperature control circuit
1 Introduction
Now the gas sensors are widely used, such as environmental monitoring, air quality control, automotive and medical care. However, there are commercial high cost of gas sensors. In addition, the relatively high power consumption also makes them in the light of the battery-powered applications on handheld devices is not practical. CMOS integrated monolithically integrated gas sensor module to reduce the above shortcomings is a promising approach. CMOS not only because of mass production methods help to reduce costs, and can obtain reliable, repeatable performance [1]. Meanwhile, the on-chip CMOS circuitry is conducive to intelligent signal conditioning and monitoring.
Most of the resistance of gas sensors using metal oxide-sensitive materials. Metal oxides (such as tin oxide [2], zinc oxide [3]) high temperature conditions in the appropriate (200 ° C -400 º C) can react with different gases, and their resistance will change as the gas concentrations Change. Therefore, resistance changes, and the optimum temperature and gas concentration can be inferred the type. However, under the high temperature reaction requires very large energy. In addition, the overall design of the circuit, on a single chip to accommodate a high-temperature region is a technical challenge. To overcome this problem, the heating circuit chip area must be isolated. Heating module can be placed on the diaphragm [1,4]. For the high temperature gas sensors
混合信號溫度控制電路
1 簡介
現(xiàn)在氣體傳感器被廣泛的應(yīng)用,如環(huán)境監(jiān)測,空氣質(zhì)量控制,汽車和醫(yī)療保健。然而,目前得到商用的氣體傳感器的成本很高。此外,相對較高的功耗也使得它們在輕便的電池供電的手持式儀器上的應(yīng)用不太實(shí)際。集成了氣體傳感器的CMOS單片集成模塊在減少上述缺點(diǎn)方面是一個(gè)很有前景的方法。因?yàn)镃MOS的批量生產(chǎn)方式不僅有助于降低成本,而且可以得到可靠的重復(fù)性能[1]。同時(shí),片上CMOS電路有利于實(shí)現(xiàn)信號的智能調(diào)節(jié)和監(jiān)控。
氣體傳感器的電阻大多采用金屬氧化物敏感材料。金屬氧化物(例如錫氧化物[2],氧化鋅[3])在適合的高溫條件下(200°C -400ºC)可以與不同的氣體發(fā)生反應(yīng),它們的電阻會隨著氣體濃度的變化而發(fā)生變化。因此,從電阻的變化以及反應(yīng)的最佳溫度可以推斷出濃度和氣體的類型。然而,高溫條件下的反應(yīng)需要非常大的能量。此外,在整體設(shè)計(jì)電路時(shí),在一塊芯片上容納一個(gè)高溫區(qū)域是一項(xiàng)技術(shù)挑戰(zhàn)。為了克服這個(gè)問題,加熱區(qū)域必須與片上電路相隔離??梢詫⒓訜崮K置于隔膜上[1,4]。對于高溫氣體傳感器來說,監(jiān)測和控制溫度同樣非常重要,因?yàn)橥环N溫度敏感材料在不同的溫度下可以感知多種氣體[5]。更進(jìn)一步來說,由于氣體敏感材料的性質(zhì)和厚度,以及材料沉積后造成的能量消耗增加,僅僅從能量的消耗來預(yù)測溫度是不夠準(zhǔn)確的。為了提高準(zhǔn)確性和氣體傳感器的性能,片上溫度控制電路是必需的。