1、中英文资料外文翻译文献 毕业论文中英文资料外文翻译文献外文资料DS1722 Digital ThermometerWith scientific and technological progress and development of the types of temperature sensors increasingly wide range of application of the increasingly widespread, and the beginning analog toward digital, single-bus, dual-bus and bus-3 direc
2、tion. And the number of temperature sensors because they apply to all microprocessor interface consisting of automatic temperature control system simulation can be overcome sensor and microprocessor interface need signal conditioning circuit and A / D converters advantages of the drawbacks, has been
3、 widely used in industrial control, electronic transducers, medical equipment and other temperature control system. Among them, which are more representative of a digital temperature sensor DS18B20, MAX6575, the DS1722, MAX6636 other. This paper introduces the DS1722 digital temperature sensor chara
4、cteristics, the use of the method and its timing. Internal structure and other relevant content. FEATURES:Temperature measurements require no external components;Measures temperatures from -55C to +120C. Fahrenheit equivalent is -67F to +248F;Thermometer accuracy is 2.0C;Thermometer resolution is co
5、nfigurable from 8 to 12 bits (1.0C to 0.0625Cresolution);Data is read from/written to via a Motorola Serial Peripheral Interface (SPI) or standard 3-wire serial interface;Wide analog power supply range (2.65V - 5.5V);Separate digital supply allows for 1.8V logic;Available in an 8-pin SOIC (150 mil),
6、 8-pin USOP, and flip chip package;PIN ASSIGNMENTFIGURE 1 PIN ASSIGNMENTPIN DESCRIPTION:SERMODE - Serial Interface Mode.CE - Chip Enable.SCLK - Serial Clock.GND Ground.VDDA - Analog Supply Voltage.SDO - Serial Data Out.SDI - Serial Data In.VDDD - Digital Supply Voltage.DESCRIPTION:The DS1722 Digital
7、 Thermometer and Thermostat with SPI/3-Wire Interface provides temperature readings which indicate the temperature of the device. No additional components are required; the device is truly a temperature-to-digital converter. Temperature readings are communicated from the DS1722 over a Motorola SPI i
8、nterface or a standard 3-wire serial interface. The choice of interface standard is selectable by the user. For applications that require greater temperature resolution, the user can adjust the readout resolution from 8 to 12 bits. This is particularly useful in applications where thermal runaway co
9、nditions must be detected quickly.For application flexibility, the DS1722 features a wide analog supply rail of 2.65V - 5.5V. A separate digital supply allows a range of 1.8V to 5.5V. The DS1722 is available in an 8-pin SOIC (150-mil), 8-pin USOP, and flip chip package.Applications for the DS1722 in
10、clude personal computers/servers/workstations, cellular telephones, office equipment, or any thermally-sensitive system.OVERVIEW:A block diagram of the DS1722 is shown in Figure 2. The DS1722 consists of four major components:1. Precision temperature sensor.2. Analog-to-digital converter.3. SPI/3-wi
11、re interface electronics.4. Data registers.The factory-calibrated temperature sensor requires no external components. The DS1722 is in a power conserving shutdown state upon power-up. After power-up, the user may alter the configuration register to place the device in a continuous temperature conver
12、sion mode or in a one-shot conversion mode. In the continuous conversion mode, the DS1722 continuously converts the temperature and stores the result in the temperature register. As conversions are performed in the background, reading the temperature register does not affect the conversion in progre
13、ss. In the one-shot temperature conversion mode, the DS1722 will perform one temperature conversion, store the result in the temperature register, and then eturn to the shutdown state. This conversion mode is ideal for power sensitive applications. More information on the configuration register is c
14、ontained in the “OPERATION-Programming” section. The temperature conversion results will have a default resolution of 9 bits. In applications where small incremental temperature changes are critical, the user can change the conversion resolution from 9 bits to 8, 10, 11, or 12. This is accomplished
15、by programming the configuration register. Each additional bit of resolution approximately doubles the conversion time. The DS1722 can communicate using either a Motorola Serial Peripheral Interface (SPI) or standard 3-wire interface. The user can select either communication standard through the SER
16、MODE pin, tying it to VDDD for SPI and to ground for 3-wire. The device contains both an analog supply voltage and a digital supply voltage (VDDA and VDDD, respectively). The analog supply powers the device for operation while the digital supply provides the top rails for the digital inputs and outp
17、uts. The DS1722 was designed to be 1.8V Logic-Ready.DS1722 FUNCTIONAL BLOCK DIAGRAM Figure 2OPERATION-Measuring Temperature:The core of DS1722 functionality is its direct-to-digital temperature sensor. The DS1722 measures temperature through the use of an on-chip temperature measurement technique wi
18、th an operating range from -55to +120C. The device powers up in a power-conserving shutdown mode. After power-up, the DS1722 may be placed in a continuous conversion mode or in a one-shot conversion mode. In the continuous conversion mode, the device continuously computes the temperature and stores
19、the most recent result in the temperature register at addresses 01h (LSB) and 02h (MSB). In the one-shot conversion mode, the DS1722 performs one temperature conversion and then returns to the shutdown mode, storing temperature in the temperature register. Details on how to change the setting after
20、power up are contained in the “OPERATION-Programming” section. The resolution of the temperature conversion is configurable (8, 9, 10, 11, or 12 bits), with 9-bit readings the default state. This equates to a temperature resolution of 1.0C, 0.5C, 0.25C, 0.125C, or 0.0625C. Following each conversion,
21、 thermal data is stored in the thermometer register in twos complement format; the information can be retrieved over the SPI or 3-wire interface with the address set to the temperature register, 01h (LSB) and then 02h (MSB). Table 2 describes the exact relationship of output data to measured tempera
22、ture. The table assumes the DS1722 is configured for 12-bit resolution; if the evince is configured in a lower resolution mode, those bits will contain 0s. The data is transmitted serially over the digital interface, MSB first for SPI communication and LSB first for 3-wire communication. The MSB of
23、the temperature register contains the “sign” (S) bit, denoting whether the temperature is positive or negative. For Fahrenheit usage, a lookup table or conversion routine must be used. AddressLocationS2625242322212002hMSB (unit = ) LSB2-12-22-32-4000001hTEMPERATUREDIGITAL OUTPUT(BINARY)DIGITAL OUTPU
24、T(HEX)+1200111 1000 0000 00007800h+25.06250001 1001 0001 00001910h+10.1250000 1010 0010 00000a20h+0.50000 0000 1000 00000080h00000 0000 0000 00000000h-0.51111 1111 1000 0000Ff80h-10.1251111 0101 1110 0000F5e0h-25.06251110 0110 1111 0000E6f0h-551100 1001 0000 0000C900hOPERATION-Programming:The area o
25、f interest in programming the DS1722 is the Configuration register. All programming is done via the SPI or 3-wire communication interface by selecting the appropriate address of the desired register location. Table 3 illustrates the addresses for the two registers (configuration and temperature) of
26、the DS1722.Register Address Structure Table 3Read AddressWrite AddressActive Register00h80hConfiguration01hNo accessTemperature LSB02hNo accessTemperature MSBCONFIGURATION REGISTER PROGRAMMING:The configuration register is accessed in the DS1722 with the 00h address for reads and the 80h address for
27、 writes. Data is read from or written to the configuration register MSB first for SPI communication and LSB first for 3-wire communication. The format of the register is illustrated in Figure 2. The effect each bit has on DS1722 functionality is described below along with the power-up state of the b
28、it. The entire register is volatile, and thus it will power-up in the default state.CONFIGURATION/STATUS REGISTER Figure 21SHOT = One-shot temperature conversion bit. If the SD bit is 1, (continuous temperature conversions are not taking place), a 1 written to the 1SHOT bit will cause the DS1722 to
29、perform one temperature conversion and store the results in the temperature register at addresses 01h (LSB) and 02h (MSB). The bit will clear itself to 0 upon completion of the temperature conversion. The user has read/write access to the 1SHOT bit, although writes to this bit will be ignored if the
30、 SD bit is a 0, (continuous conversion mode). The power-up default of the one-shot bit is 0.R0, R1, R2 = Thermometer resolution bits. Table 4 below defines the resolution of the digital thermometer, based on the settings of these 3 bits. There is a direct tradeoff between resolution and conversion t
31、ime, as depicted in the AC Electrical Characteristics. The user has read/write access to the R2, R1 and R0 bits and the power-up default state is R2=0, R1=0, and R0=1 (9-bit conversions).THERMOMETER RESOLUTION CONFIGURATION Table 4R2R1R0ThermometerResolutionMaxConversionTime0008-bit0.075s0019-bit0.1
32、5s01010-bit0.3s01111-bit0.6s1xx12-bit1.2sSD = Shutdown bit. If SD is 0, the DS1722 will continuously perform temperature conversions and store the last completed result in the temperature register. If SD is changed to a 1, the conversion in progress will be completed and stored and then the device w
33、ill revert to a low-power shutdown mode. The communication port remains active. The user has read/write access to the SD bit and the power-up default is 1 (shutdown mode).SERIAL INTERFACE:The DS1722 offers the flexibility to choose between two serial interface modes. The DS1722 can communicate with
34、the SPI interface or with a standard 3-wire interface. The interface method used is determined by the SERMODE pin. When this pin is connected to VDDD SPI communication is selected. When this pin is connected to ground, standard 3-wire communication is selected.SERIAL PERIPHERAL INTERFACE (SPI):The s
35、erial peripheral interface (SPI) is a synchronous bus for address and data transfer. The SPI mode of serial communication is selected by tying the SERMODE pin to VDDD. Four pins are used for the SPI. The four pins are the SDO (Serial Data Out), SDI (Serial Data In), CE (Chip Enable), and SCLK (Seria
36、l Clock). The DS1722 is the slave device in an SPI application, with the microcontroller being the master. The SDI and SDO pins are the serial data input and output pins for the DS1722, respectively. The CE input is used to initiate and terminate a data transfer. The SCLK pin is used to synchronize
37、data movement between the master (microcontroller) and the slave (DS1722) devices. The shift clock (SCLK), which is generated by the microcontroller, is active only when CE is high and during address and data transfer to any device on the SPI bus. The inactive clock polarity is programmable in some
38、microcontrollers. The DS1722 offers an important feature in that the level of the inactive clock is determined by sampling SCLK when CE becomes active. Therefore, either SCLK polarity can be accommodated. There is one clock for each bit transferred. Address and data bits are transferred in groups of
39、 eight, MSB first.3-WIRE SERIAL DATA BUS:The 3-wire communication mode operates similar to the SPI mode. However, in 3-wire mode, there is one bi-directional I/O instead of separate data in and data out signals. The 3-wire consists of the I/O (SDI and SDO pins tied together), CE, and SCLK pins. In 3
40、-wire mode, each byte is shifted in LSB first unlike SPI mode where each byte is shifted in MSB first. As is the case with the SPI mode, an address byte is written to the device followed by a single data byte or multiple data bytes.外文资料译文DS1722数字温度传感器随着科学技术的不断进步和发展,温度传感器的种类日益繁多,应用逐渐广泛,并且开始由模拟式向着数字式、
41、单总线式、双总线式和三总线式发展。而数字温度传感器更因适用于各种微处理器接口组成的自动温度控制系统具有可以克服模拟传感器与微处理器接口时需要信号调理电路和A/D转换器的弊端等优点,被广泛应用于工业控制、电子测温计、医疗仪器等各种温度控制系统中。其中,比较有代表性的数字温度传感器有DS18B20、MAX6575、DS1722、MAX6636等。本文主要介绍了数字温度传感器DS1722的特性、使用方法以及它的时序、内部结构等相关内容。特点:(1) 温度测量无需外部元件。(2) 测量温度范围从-55至+120,华氏等量温度为-67248。(3) 温度测量精度为2.0 。(4) 温度测量配置可为8位至
42、12位分辨率(即1.0至0.0625分辨率)。(5) 数据读写接口方式可以是Motorola串行外设接口或三线串行接口。(6) 模拟电源电压范围(2.65V到5.5V )。(7) 单独的逻辑数字电压允许在1.8V。(8) 具有8管脚SOIC(150 mil )封装和8管脚USOP封装两种封装形式。图1 管脚图管脚描述:SERMODE-串行接口模式CE-芯片使能SCLK-串行时钟线GND-地VDDA-模拟电源电压SDO-串行数据输出SDI-串行数据输入VDDD-数字电源电压描述:具有SPI接口和三总线接口的DS1722数字温度传感器是一个可以对温度进行读取的装置。对温度测量不需要外部元件辅助,它
43、是一个真正的温度-数字转换器。温度数据通信通过DS1722 的Motorola SPI 接口或者一个标准三总线 串行接口来实现。接口标准选择由用户自己来决定。应用中,如要求更大温度分辨率,用户可以调整分辨率从8位至12位。在必须迅速侦查到热失控的情况下,这是特别方便的应用。应用的灵活性,DS1722芯片的模拟供电电压范围为2.65V到5.5V,而一个单独的数字电压供电允许范围为1.8V至5.5V。 DS1722具有8管脚SOIC(150 MIL )封装和8管脚USOP封装两种封装形式。DS1722的应用领域可以涉及到个人计算机/服务器/工作组,单元电话,办公设备,或任何热敏感系统。概况:DS1
44、722的内部结构方框图如图2所示:图2 内部结构方框图数字温度传感器DS1722由四个主要部分成:精密温度传感器。(1) 模数转换器。(2) SPI/三线接口电子器件。(3) 数据寄存器。(4) 这种温度传感器无需外部元件.开始供电时,DS1722处于能量关闭状态,供电之后,用户通过改变寄存器分辨率使其处于连续转换温度模式或者单一温度转换模式.连续转换模式下,DS1722连续转换温度并将结果存于温度寄存器中,如同转换只是一种背景,读温度寄存器中的内容不影响其温度转换;在单一转换模式,DS1722执行一次温度转换,结果存于温度寄存器中,然后回到关闭模式,这种转换模式适用于对温度敏感的应用场合。更
45、多关于配置寄存器的内容包含在“编程操作”部分。温度转换结果的默认分辨率为9位。在应用中,小增量温度变化是至关重要的, 用户可以通过改变分辨率寄存器来实现不同的温度分辨率,从第9位可以改变到8位 、10位、11或12,这些是通过程序配置寄存器来完成。但每增加一位大约增加一倍的转换时间。DS1722有摩托罗拉串行接口和标准三线接口两种通信接口,用户可以通过SERMODE管脚来选择通信标准,SERMODE管脚接VDDD为SPI接口,SERMODE管脚接地为标准三线接口。该装置包含一个模拟电源电压和一个数字电源电压( 即:VDDA和VDDD),模拟电源电压供给装置的运行,而数字电源电压供应数字输入和输
46、出.DS1722是为1.8V逻辑电压而设计准备的。温度测量操作:DS1722 功能核心是它是以直接数字式温度传感器来工作的。DS1722 温度测量通过一个芯片温度测量技术来实现,测量范围从-55到+120。该装置在供电前处于待机模式,在供电后,DS1722可可能会被置于续转换模式或单一转换模式。在连续转换模式状态下,该装置连续计算温度并把测温数据的最新结果存储在温度寄存器的地址位01H(LSB)和02H(MSB);在单一转换模式状态下,DS1722执行一次温度转换,结果存于温度寄存器中,然后回到关闭模式。关于详细介绍在供殿后如何更改设置包含在“编程操作”部分。温度转换分辨率配置可以分为(8,9
47、,10,11,12位),且在默认状态下为9位;其对应分辨率分别为1.0,0.5,0.25,0.125,和0.0625。传感器DS1722将温度转换后以二进制的补码格式存储于温度寄存器中,通过SPI或者三线接口,温度寄存器中的地址01H(LSB)和02H(MSB)中的数据可以被读出来,表2描述了输出的数据与被测量的温度的确切关系,表中假设DS1722配置为12位分辨率;如果设备被配置在一个低分辨率方式下,那些位将包含0s。数据通过数字接口连续传送,MSB首先通过SPI传输,LSB首先通过三线传输。温度寄存器器的MSB包含“标志”(s)位,表示温度是正值或负值。若为华氏用法,必须使用查表或转换规则。表2 温度与地址数据格式关系S2625242322212002hMSB (单位为) LSB2-12-22-32-4000001h温度值数字输入(二进制)数字输出(十六进制)+1200111 1000 0000 00007800h+25.06250001 1001 0001 00001910h+10.1250000 1010 0010 00000a2
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