温度计通过传导或对流达到热平衡，从而使温度计的示值能直接表示被测对象的温度。一般测量精度较高。在一定的测温范围内，温度计也可测量物体内部的温度分布。但对于运动体、小目标或热容量很小的对象则会产生较大的测量误差，常用的温度计有双金属温度计、玻璃液体温度计、压力式温度计、电阻温度计、热敏电阻和温差电偶等。它们广泛应用于工业、农业、商业等部门。在日常生活中人们也常常使用这些温度计。随着低温技术在国防工程、空间技术、冶金、电子、食品、医药和石油化工等部门的广泛应用和超导技术的研究，测量120K以下温度的低温温度计得到了发展，如低温气体温度计、蒸汽压温度计、声学温度计、顺磁盐温度计、量子温度计、低温热电阻和低温温差电偶等。低温温度计要求感温元件体积小、准确度高、复现性和稳定性好。利用多孔高硅氧玻璃渗碳烧结而成的渗碳玻璃热电阻就是低温温度计的一种感温元件，可用于测量1.6～300K范围内的温度。-DS18B20 memory includes a cache RAM and can be electrically erased RAM, which can be electrically erased RAM and temperature trigger TH and TL, as well as a configuration register. Memory can complete to determine the first port in communication, digital began to write register command written into the register, then can also register read command to confirm these numbers. When it is confirmed that it can be used after the copy register command to add these figures shifted to an electrically erasable RAM. When the modified register number, this process can ensure the integrity of digital.



High speed register RAM is composed of 8 bytes of memory　the first and second bytes of the temperature of the display position. Third and fourth byte is the replication of TH and TL, while the third and fourth bytes of digital can update　fifth bytes is to copy the configuration register, and fifth bytes of digital can update　six or seven, eight three bytes of computer use. Use register read comm