数控直流电流源(F 题)设计与总结报告摘 要 : 本 设 计 基 于 单 片 机 控 制 技 术 , 系 统 以 单 片 机 AT89S51 为 核 心 ,TLC5615,TLC1549,ZLG7289 等元件构成辅助电路,采纳 D/A 转换输出可变电压和利用压控恒流源,差动放大与信号调节电路实现对数控直流电流源的控制。系统可预置输出电流,通过采样将实际输出反馈到单片机中构成闭环系统,进行比较、调整,提高了电流的输出精度 。关键词:单片机、压控恒流源、D/A 转换Abstract: This design based on the Singlechip Control Technology. The system takes singlechip AT89S51 as the core, and takes the TLC5615, TLC1549, ZLG7289 and other devices to constitute the auxiliary circuit. It produces changeable voltage by using D/A conversion. It implements the control to the numerical controlled direct current source by using the voltage controlled constant current source, differential amplification and signal adjustment circuit. The system can preset output current, feed back the actual output through sampling to the singlechip to constitute the closed loop system, carry on comparison and adjustment, and increase the electric current output precision.Keywords: singlechip, voltage controlled constant current source, D/A conversion.目录1. 系统设计……………………………………………………………………………………31.1 设计要求……………………………………………………………………………………31.2 总体设计方案………………………………………………………………………………3 设计思路…………………………………………………………………………………3 方案论证与比较………………………………………………………………………… 3 系统组成…………………………………………………………………………………52. 单元电路设计……………………………………………………………………………… 52.1D/A 转换电路 …………………………………………………………………………… 52.2 键盘显示电路 …………………………………………………………………………… 62...