簡介：采用支持菊鏈模式的新型數(shù)字溫度傳感器芯片DS28EA00組建的單總線測溫網(wǎng)絡(luò)。無需進(jìn)行傳統(tǒng)的ROM搜索步驟，允許用戶將器件在鏈路中的物理位置與序列號對應(yīng)，節(jié)省了RAM開銷，簡化了基于單總線的應(yīng)用設(shè)計(jì)。
    
基本特點(diǎn)：

DS28EA00數(shù)字溫度傳感器是具有9位(0.5℃)至12位(1/16℃)分辨率和用戶可編程非易失性(NV)上、下觸發(fā)點(diǎn)報(bào)警功能的數(shù)字溫度計(jì)。每個(gè)DS28EA00都具工廠編程的唯一64位序列號。通信時(shí)只需一根數(shù)據(jù)線和地線，就可通過1-Wire?協(xié)議串行傳輸數(shù)據(jù)。改進(jìn)型1-Wire接口具有滯回和干擾濾波功能，使得DS28EA00能夠在大的1-Wire網(wǎng)絡(luò)中可靠工作。與其他1-Wire溫度計(jì)不同，DS28EA00具有兩個(gè)額外的引腳用以執(zhí)行順序檢測功能。該特性允許用戶將器件在鏈路中的物理位置與序列號對應(yīng)，例如，用來測量儲存塔不同高度處的溫度。如果無需順序檢測功能，這些引腳可作為通用輸入或輸出。DS28EA00能夠直接從數(shù)據(jù)線獲取電源進(jìn)行工作("寄生供電")，因此無需外部電源。

·數(shù)字溫度計(jì)測量范圍：-40℃至+85℃

·用戶可選擇的9至12位溫度分辨率

·獨(dú)特的1-Wire接口，僅需單個(gè)引腳即可進(jìn)行通信

·每個(gè)器件都具有在工廠激光刻蝕的唯一64位序列號

·ROM多節(jié)點(diǎn)能力簡化分布式溫度檢測應(yīng)用

·具有滯回和干擾濾波器的改進(jìn)型1-Wire接口

·用戶可定義的非易失性(NV)報(bào)警溫度設(shè)置/用戶字節(jié)

·報(bào)警搜索命令能夠快速確定溫度超出設(shè)定范圍的器件

·標(biāo)準(zhǔn)和高速1-Wire通信模式

·2個(gè)通用可編程IO (PIO)引腳

·級聯(lián)功能使用PIO引腳檢測器件在網(wǎng)絡(luò)中的物理順序

·工作范圍：3.0V至5.5V，-40℃至+85℃

·可由數(shù)據(jù)線供電

方案特點(diǎn)

The DS28EA00 evaluation system (EV system) consists of a single evaluation kit (EV kit) that includes an evaluation board (EV board) made up of three subsections that can be broken/snapped off into three independently exercisable boards. Since one of the major features of the DS28EA00 is detection of physical sequence, a block of dip switches are provided on each subsection of the EV board to re-order the physical connection between the chips. Optionally, the customer can break off the subsections of the eval board, connect them together with the provided cables, and re-order the physical sequence of the DS28EA00s that way.

Easy Setup 

Stand-Alone EV Board 

Contains Three Separate, Breakable Subsections with a DS28EA00 Per Subsection 

The Dipswitch Block on Each EV Board Subsection Routes Physical Chain-Mode

Connections Between Chips When Used as a Stand-Alone Board

EV Board’s Subsections are Breakable Into Three Separate Boards Each of Which  Evaluates a Single DS28EA00 or, When Cabled Together, Evaluate Chain-Mode Searching

LEDs Give Visual Indicators of PIO Activity

6-Pin Terminal Strip Allows PIO Testing Outside of Chain Mode

PC Connectivity Included

RoHS Compliant

Free Downloadable Evaluation Software Available

參考原理圖 



                                 圖1 參考原理圖

參考pcb圖



                                  圖2 參考layout top

  

圖3 參考layout bottom



圖4： 參考layout composite

詳情請見：http://datasheets.maximintegrated.com/en/ds/DS28EA00EVKIT.pdf