數(shù)字溫度傳感器外文翻譯6(完整版)
【正文】 B20 is used in parasite power mode, the VDD pin must be connected to ground. In parasite power mode, the 1Wire bus and CPP can provide sufficient current to the DS18B20 for most operations as long as the specified timing and voltage requirements are met. However, when the DS18B20 is performing temperature conversions or copying data from the scratchpad memory to EEPROM, the operating current can be as high as . This current can cause an unacceptable voltage drop across the weak 1Wire pull up resistor and is more current than can be supplied by CPP. To assure that the DS18B20 has sufficient supply current, it is necessary to provide a strong pull up on the 1Wire bus whenever temperature conversions are taking place or data is being copied from the scratchpad to EEPROM. DS18B20 數(shù)字溫度傳感器提供 912 位的分辨率而且還有一種報(bào)警功能，它內(nèi)部有非易失的用戶可編程的單元用來(lái)設(shè)置溫度的上限和下限。 每個(gè) DS18B20 都有唯一的 64 位序列號(hào)。上下限寄存器和配置寄存器都是用非可易失性的材料做的，所以在掉電之后也 不會(huì)丟失數(shù)據(jù)。 DS18B20 的核心部位是其可以直接將外界溫度信息直接轉(zhuǎn)換成數(shù)字信號(hào)的溫度傳感器。溫度值在 DS18B20 中是以兩字節(jié)的補(bǔ)碼形式存儲(chǔ)在溫度傳感器中的。當(dāng) DS18B20 工作在寄生電源模式時(shí)，單總線和 CPP 能夠?yàn)槠浯蟛糠值牟僮魈峁┳銐虻碾娫础Ｈ绻?9 位精度的 話，納悶第一位、第二位和第三位都沒(méi)有定義 DS18B20 既可以通過(guò) VDD 管腳來(lái)提供額外的電源，也可以通過(guò)寄生電源的方式來(lái)為其自身供電。在傳感器接收到命令之后，并作出反應(yīng)后，溫度值被存儲(chǔ)在溫度傳感器內(nèi)部的兩字節(jié)的溫度寄存器中，這兩個(gè)字節(jié)在斷電后會(huì)丟失數(shù)據(jù)，然后溫度傳感器恢復(fù)等待命令狀態(tài)（即空閑狀態(tài)）。 DS18B20 另一個(gè)特征是它不需要額外的供電系統(tǒng)。 正如上面所說(shuō)的 64 位的 ROM 中存儲(chǔ)這溫度傳感器的唯一序列號(hào)。C，而且在 –10176。C to +85176。C. 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 64bit serial code, which allows multiple DS18B20s to function on the sa
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