【正文】 ?55?C to 125?C 177。 3?C(max)Applications. System Thermal Management. Personal Computers. Office Electronics. Electronic Test Equipment Functional Description The LM75 temperature sensor incorporates a bandgap type temperature sensor and 9bit ADC (DeltaSigma AnalogtoDigital Converter). The temperature data output of the LM75 is available at all times via the I2C bus. If a conversion is in progress, it will be stopped and restarted after the read. A digital parator is also incorporated that pares a series of readings, the number of which is userselectable, to userprogrammable setpoint and hysteresis values. The parator trips the . output line, which is programmable for mode and polarity. The LM75B contains all the functionality of the LM75C, plus two additional features:1. The LM75B has an integrated lowpass filter on both theSDA and the SCL line. These filters increase munications reliability in noisy environments.2. The LM75B also has a bus fault timeout feature. If the SDA line is held low for longer than tTIMEOUT(75 ms minimum to 325 ms maximum) the LM75B will reset to the IDLE state (SDA set to high impedance) and wait for a new start condition. . OUTPUT, TOS AND THYST LIMITSIn Comparator mode the . Output behaves like a thermostat. The output bees active when temperature exceeds the TOS limit, and leaves the active state when the temperature drops below the THYST limit. In this mode the . output can be used to turn a cooling fan on, initiate an emergency system shutdown, or reduce system clock speed. Shutdown mode does not reset . state in a parator mode.In Interrupt mode exceeding TOS also makes . active but . will remain active indefinitely until reset by reading any register via the I2C interface. Once . has been activated by crossing TOS, then reset, it can be activated again only by Temperature going below THYST. Again, it will remain active indefinitely until being reset by a read. Placing the LM75 in shutdown mode also resets the . Output. POWER UP AND POWER DOWNThe LM75 always powers up in a known state. The power updefault conditions are:1. Comparator mode2. TOS= 80?C3. THYST= 75?C4. . active low5. Pointer = “00”If the LM75 is not connected to the I2C bus on power up, it will act as a standalone thermostat with the above temperature settings.When the supply voltage is less than about , the LM75 is considered powered down. As the supply voltage rises above the nominal power up threshold, the internal registers are reset to the power up default values listed above. SHUTDOWN MODEShutdown mode is enabled by setting the shutdown bit in the Configuration register via the I2C bus. Shutdown mode reduces power supply current to 4 181。A typical. In Interrupt mode . is reset if previously set and is undefined in Comparator mode during shutdown. The I2C interface remains active. Activity on the clock and data lines of the I2C bus may slightly increase shutdown mode quiescent current. TOS, THYST, and Configuration registers can be read from and written to in shutdown mode. FAULT QUEUEA fault queue of up to 6 faults is provided to prevent false tripping of . when the LM75 is used in noisy environments. The number of faults set in the queue must occur consecutively to set the . Output. COMPARATOR/INTERRUPT MODEAs indicated in the . Output Temperature Response Diagram, Figure 4 , the events that trigger . are identical for either Comparator or Interrupt mode. The most important difference is that in Interrupt mode the . will remain set indefinitely once it has been set. To reset . while in Interrupt mode, perform a read from any register in the LM75. . OUTPUTThe . output is an opendrain output and does not have an internal pullup. A “high” level will not be observed on this pin until pullup current is provided from some external source, typically a pullup resistor. Choice of resistor value depends on many system factors but, in general, the pullup resistor should be as large as possible. This will minimize any errors due to internal heating of the LM75. The maximum resistance of the pull up, based on LM75 specification for High Level Output Current, to provide a 2V high level, is 30 k ?.西昌學(xué)院 系畢業(yè)論文（設(shè)計）指導(dǎo)教師指導(dǎo)記錄表畢業(yè)論文題目： 學(xué)生姓名： 學(xué)號： 專業(yè)： 指導(dǎo)教師： 序號指導(dǎo)日期指導(dǎo)內(nèi)容學(xué)生簽名1234567891011121314151617181920前期存在的主要問題與解決措施中期存在的主要問題與解決措施后期存在的主要問題與解決措施注：本表由學(xué)生填寫。指導(dǎo)教師每周的指導(dǎo)次數(shù)不得少于1次，總的指導(dǎo)次數(shù)不得低于20次。畢業(yè)論文(設(shè)計)成績評定表（指導(dǎo)教師用）題目名稱學(xué)生姓名學(xué)號年級、專業(yè)指導(dǎo)教師職稱教研室評價內(nèi)容 評價指標(biāo)滿分評分調(diào)查論證、實(shí)驗(yàn)方案設(shè)計、實(shí)驗(yàn)技能能獨(dú)立查閱文獻(xiàn)和從事其它調(diào)研，能正確翻譯外文資料；能提出并較好地論述課題的實(shí)施方案；有收集加工各種信息及獲取新知識的能力。能正確設(shè)計實(shí)驗(yàn)方案，獨(dú)立進(jìn)行實(shí)驗(yàn)工作，如設(shè)備安裝，調(diào)試和操作等。30分析與解決問題的能力能運(yùn)用所學(xué)知識和技能去發(fā)現(xiàn)與解決實(shí)際問題；能正確處理實(shí)驗(yàn)數(shù)據(jù)；能對課題進(jìn)行理論分析，并得出有價值的結(jié)論。20工作量、工作態(tài)度按期圓滿完成規(guī)定的任務(wù)，工作量飽滿，難度較大；工作努力，遵守紀(jì)律；工作作風(fēng)嚴(yán)謹(jǐn)扎實(shí)。20論文(設(shè)計)質(zhì)量立論正確，論述充分，結(jié)論嚴(yán)謹(jǐn)合理；實(shí)驗(yàn)正確，分析、處理問題科學(xué)；文字通順，技術(shù)用語準(zhǔn)確，符號統(tǒng)一、編號齊全、書寫工整規(guī)范。圖表完備、整潔、正確；設(shè)計(論文)有應(yīng)用價值。20創(chuàng) 新工作中有創(chuàng)新意識；對前人工作有改進(jìn)或突破或有獨(dú)特見解。10是否同意送評閱人評議：總得分評語： 指導(dǎo)教師（簽字）： 年 月 日 54 畢業(yè)論文(設(shè)計)成績評定表（評閱人用）題目名稱學(xué)生姓名學(xué)號年級、專業(yè)指導(dǎo)教師職稱教研室評價內(nèi)容評價指標(biāo)滿分評分翻譯資料等查閱文獻(xiàn)有一定的廣泛性；翻譯外文資料的質(zhì)量較好；有綜合歸納資料的能力和有自己的見解。15文章質(zhì)量立論正確，論述充分，結(jié)論嚴(yán)謹(jǐn)合理；實(shí)驗(yàn)正確，分析、處理問題科學(xué)，文字通順，技術(shù)用語準(zhǔn)確，符號統(tǒng)一，編號齊全，書寫工整規(guī)范，圖表完備、整潔、正確；論文(設(shè)計)有應(yīng)用價值。50工作量及難度工作量飽滿、難度較大。25創(chuàng) 新對前人工作有改進(jìn)或突破或有獨(dú)特見解。10是否同意參加答辯：總得分評語： 評閱人（簽字）： 年 月 日畢業(yè)論文(設(shè)計)成績評定表（答辯小組用）題目名稱學(xué)生姓名學(xué)號年級、專業(yè)指導(dǎo)教師職稱教研室答辯委員會（小組）成員答辯委員會（小組）成員職稱評價內(nèi)容評價指標(biāo)總分評分論文、設(shè)計內(nèi)容思路清晰；語言表達(dá)準(zhǔn)確，概念清楚，論點(diǎn)正確；實(shí)驗(yàn)方法科學(xué)，分析歸納合理；結(jié)論嚴(yán)謹(jǐn)；論文(設(shè)計)有應(yīng)用價值。50創(chuàng) 新