供电(Powering) DS18B20支持两种供电模式,一种是寄生供电(parasite power),另一种是外部供电(external power)。寄生供电是将18b20的1,3脚接地 直接“窃取”DQ上的电压,这种方式操作起来似乎不太稳定。所以我使用了外部电源供电(开发板上正好有5V的直流电源比较方便) 1-WIRE BUS SYSTEM(单总线系统) 这个比较有意思,...
(±°C)Parasite Pwr.Temp. Thresh.Temp. Resolution (bits)Multi DroppableOper. Temp. (°C)Package/PinsBudgetary Price See Notes DS18B20Local1-WireOne0.5YesProgrammable (NV) 9 10 11 12 Yes-55 to +125 µMAX/8 SOIC(N)/8 TO92/3
Parasite power +3.0 4.0 V + 0.3 DD Sink Current Standby Current Active Current DQ Input Current Drift V = 0.4V mA nA mA µA °C I/O I (Notes 7, 8) V = 5V (Note 9) DD 750 1 1000 1.5 DDS I DD DQ I (Note 10) (Note 11) 5 ±...
accurate to ±0.5°C over the range of -10°C to +85°C. In addition, the DS18B20 can derive power directly from the data line (“parasite power”), eliminating the need for an external power supply.二、FEATURES:1.Can Be Powered from Data Line; Power Supply Range is 3.0V to ...
The advantages ofparasite power are twofold: 1) by parasiting off this pin, no local po 16、wer source is needed for remotesensing of temperature, and 2) the ROM may be read in absence of normal power.In order for the DS18B20 to be able to perform accurate temperature conversions, ...
directlyfromthedataline(“parasitepower”),eliminatingtheneedforanexternalpowersupply. EachDS18B20hasaunique64-bitserialcode,whichallowsmultipleDS18B20stofunctiononthesame 1-Wirebus.Thus,itissimpletouseonemicroprocessortocontrolmanyDS18B20sdistributedoveralarge ...
In addition, the DS18B20 can derive power directly from the data line (“parasite power”), eliminating the need for an external power supply. Each DS18B20 has a unique 64-bit serial code, which allows multiple DS18B20s to function on the same 1-Wire bus. Thus, it is simple to use one...
DS18S20 and DS1822. "parasite power" is a feature of most 1-Wire® devices, which allows them to derive power directly from the data line. The DS18B20, DS18S20 and DS1822 temperature sensors require that the VDD pin be connected to ground for parasite-power operation, which may require ...
(parasite power) 方框图(图 1)示出寄生电源电路 当 I/O 或 VDD 引脚为高电平时 这个电路便 取得 电源 只要符合指定的定时和电压要求 I/O 将提供足够的功率 标题为 单总线系统 一节 寄生电源的优点是双重的 1 利用此引脚 远程温度检测无需本地电源 2 缺少正常电源条件下 也可以读 ROM 为了使 DS1820 ...
具有节省I/O口线、资源结构简单、成本低廉、便于总线扩展和维护等诸多优点，单总线器件内部设置有寄生供电电路(ParasitePowerCircuit)。当单总线处于高电平时，一方面通过二极管VD向芯片供电，另方面对内部电容C(约800pF)充电；当单总线处于低电平时，二极管截止，内部电容c向芯片供电 ...