ds18b20单线数字
温度传感器
由dallas半导体公司生产的ds18b20型单线智能
温度传感器,属于新一代适配微处理器的智能
温度传感器,可广泛用于工业、民用、军事等领域的温度测量及控制仪器、测控系统和大型设备中。它具有体积小,接口方便,传输距离远等特点。
ds18b20性能特点
ds18b20的性能特点:①采用单总线专用技术,既可通过串行口线,也可通过其它i/o口线与微机接口,无须经过其它变换电路,直接输出被测温度值(9位二进制数,含符号位),②测温范围为-55℃-+125℃,测量分辨率为0.0625℃,③内含64位经过激光修正的只读存储器rom,④适配各种单片机或系统机,⑤用户可分别设定各路温度的上、下限,⑥内含寄生电源。
ds18b20内部结构
ds18b20内部结构主要由四部分组成:64位光刻rom,
温度传感器,非挥发的温度报警触发器th和tl,高速暂存器。ds18b20的管脚排列如图1所示。
64位光刻rom是出厂前被光刻好的,它可以看作是该ds18b20的地址序列号。不同的器件地址序列号不同。
FEATURES
Unique 1-Wire® interface requires only one
port pin for communication
Each device has a unique 64-bit serial code
stored in an onboard ROM
Multidrop capability simplifies distributed
temperature sensing applications
Requires no external components
Can be powered from data line. Power supply
range is 3.0V to 5.5V
Measures temperatures from –55°C to
+125°C (–67°F to +257°F)
0.5C accuracy from –10°C to +85°C
Thermometer resolution is user-selectable
from 9 to 12 bits
Converts temperature to 12-bit digital word in
750ms (max.)
User-definable nonvolatile (NV) alarm
settings
Alarm search command identifies and
addresses devices whose temperature is
outside of programmed limits (temperature
alarm condition)
Available in 8-pin SO (150mil), 8-pin SOP,
and 3-pin TO-92 packages
Software compatible with the DS1822
Applications include thermostatic controls,
industrial systems, consumer products,
thermometers, or any thermally sensitive
system