【正文】 基于 MSP430單片機的數(shù)控直流電流源的設(shè)計 摘要 本系統(tǒng)是一個基于單片機的數(shù)控直流電流源系統(tǒng)。采用單片機作為核心，輔以帶反饋自穩(wěn)定的串調(diào)恒壓源，可以連續(xù)設(shè)定電流值。由 D/A 轉(zhuǎn)換器TLC561 ZLG728中文字庫液晶顯示塊、放大電路和大功率調(diào)整電路組成。通過獨立鍵盤輸入給定值，由 D/A 轉(zhuǎn)換器將數(shù)字信號轉(zhuǎn)換成模擬信號，經(jīng)D/A 輸出電壓作為恒流源的參考電壓，利用晶體管平坦的輸出特性得到恒定的電流輸出，最后用中文液晶顯示輸出。其中單片機選用美國 TI 公司的MSP430F2274 作為控制核心，利用閉環(huán)控制原 理，加上反饋電路，使整個電路構(gòu)成一個閉環(huán)。軟件方面主要利用 PID 算法來實現(xiàn)對輸出電流的精確控制。系統(tǒng)可靠性高，體積小，操作簡單方便，人機界面友好。 關(guān)鍵字： 數(shù)控 MSP430 PID算法 反饋電路 單片機 Digital Controlled DC Current Source Design Based On MSP430 MCU ABSTRACT This system is a based on SCM numerical control dc current source system. Using single chip microputer as the core, with the strings with feedback from stability constant pressure source, can tone set by continuous. By D/A converter ZLG7289, Chinese word stock TLC5615, liquid crystal display (LCD) block, amplifying circuit and highpower regulating circuit ponent. The given value through independent keyboard input by D/A converter, converts digital signals into analog signals, the D/A constant current source voltage output as A reference voltage, using the plain output characteristic get the transistor constant current output, finally use Chinese LCD display output. One of the American TI pany microcontroller choose MSP430F2274 as control core, using the closedloop control principle, plus feedback circuit, make whole circuit constitute a closedloop. Mainly using PID algorithm software to achieve output current the precise control. The system reliability high, small volume, easy to operate, friendly manmachine interface. Key Words： Numerical Control MSP430 PID Algorithm Feedback Circuit SCM I 目 錄 前 言 ...................................................................................................................... 1 第一章 緒論 ............................................................................................................... 2 課題背景 .....................................................................................................................................2 數(shù)控直流電流源概述 .................................................................................................................2 電流源簡介 ..........................................................................................................................2 數(shù)控直流電流源的必要性 ..................................................................................................2 數(shù)控直流電流源簡介 ..........................................................................................................3 課題進展 .....................................................................................................................................3 后話 .............................................................................................................................................3 第二章 芯片簡介 ....................................................................................................... 4 單片機芯片 MSP430F2274........................................................................................................4 D/A 芯片 TLC5615 ....................................................................................................................5 TLC5615 功能簡介 ............................................................................................................6 TLC5615 工作原理 ............................................................................................................7 ZLG7289A 芯片介紹 .................................................................................................................8 芯片簡介 ..............................................................................................................................8 引腳說明 ..............................................................................................................................8 第三章 系統(tǒng)硬件設(shè)計 .............................................................................................. 10 總體方案設(shè)計與比較 ...............................................................................................................10 單元電路 設(shè)計 ..........................................................................................................................11 電源電路 ...........................................................................................................................11 D/A 電路 .............................................................................................................................12 恒流源電路 .......................................................................................................................12 數(shù)碼管顯示電路 ...............................................................................................................14 PROTEL 99SE 介紹 .................................................................................................................15 第四章 系統(tǒng)軟件設(shè)計 .............................................................................................. 17 程序語言介紹 ...........................................................................................................................17 機器語言 ............................................................................................................................17 匯編語言 ............................................................................................................................17 II 高級語言 ............................................................................................................................17 PID 算法介紹 ............................................................................................................................18 PID 增量式算法 .................................................................................................................18 PID 位置算法 ..................................................................................................