DS18B20是DALLAS公司生产的一线式数字温度传感器，具有3引脚TO－92小体积封装形式；温度测量范围为－55℃～＋125℃,可编程为9位～12位A/D转换精度，测温分辨率可达0.0625℃，被测温度用符号扩展的16位数字量方式串行输出，支持3V～5.5V的电压范围，使系统设计更灵活、方便；其工作电源既可在远端引入，也可采用寄生电源方式产生-DALLAS DS18B20 is produced by first-line digital temperature sensor, a 3-pin TO-92 small-size package　temperature measurement range is-55 ℃ ~+125 ℃, programmed for the 9 ~ 12-bit A/D conversion precision, the measured Temperature resolution up to 0.0625 ℃, the measured temperature of 16-bit with sign extension mode digital serial output, 3V ~ 5.5V voltage range, making the system design more flexible and convenient　its work in the remote power supply can introduce , may also have parasitic power mode