宜宾职业技术学院毕业设计简易自动电阻测试仪的硬件设计系部电子信息工程系专业名称电子信息工程技术班级电子1091班姓名古亮亮学号200910305指导教师廖建文2012年02月10日简易自动电阻测试仪的硬件设计摘要本设计由电源模块,STM32F103ZET6单片机小系统模块,OPA548构成的5V恒压模块,继电器构成的换挡测电阻模块,步进电机模块,3.2寸TFT(ThinFilmTransistor薄膜场效应晶体管)真彩触摸屏显示模块组成。该设计是通过单片机控制一个内部集成的12位DA给OPA548运放芯片输入电压,从而控制运放芯片的输出电压,再送给继电器构成的换挡测电阻模块,最后通过测试电阻上产生的电压来判断所测电阻值。其中STM32单片机小系统还控制内部集成的两个12位AD,一个采集当OPA548输出的值,构成一个闭环系统使OPA548输出恒压5V,一个采集待测电阻值,从而控制继电器换挡测出待测电阻值。关键词:STM32F103ZET612位AD/DA继电器3.2寸TFT真彩触摸屏EasyAutoresistancetesterhardwaredesignAbstractThedesignofthepowersupplymodule,STM32F103ZET6smallsingle-chipsystemmodule,OPA548constitute5vconstantpressuremodule,relaymoduleconsistingoftheshiftresistor,steppermotormodule,3.2-inchTFT(ThinFilmTransistorfilmfield-effecttransistor)colortouchscreendisplaymodule.Thedesigniscontrolledbyaninternalintegratedsingle-chip12-bitDAchiptoOPA548op-ampinputvoltage,therebycontrollingtheoutputvoltageop-ampchip,andthensenttotherelaymoduleconsistingoftheshiftresistor,andfinallybytestingthevoltageontheresistortodeterminethemeasuredresistancevalue.STM32microcontrollerwhichcontrolsasmallsystemalsointegratesthetwo12-bitAD,acollectionwhentheOPA548outputvaluetoformaclosedloopsystemsothatOPA548outputconstant5v,acollectiontestresistancevalue,therebycontrollingtherelayshiftmeasuredmeasuredresistancevalues.Keywords:STM32F103ZET6;12-bitAD/DA;relay;3.2-inch;TFTcolortouch;screen目录1引言.............................................................12系统方案论证与选择................................................22.1主控芯片的选择..............................................22.25V恒压模块的选择............................................22.3显示模块的选择..............................................33系统设计..........................................................43.1系统总框图...................................................43.2系统设计思路................................................44硬件电路设计......................................................64.1电源模块的设计...............................................64.2OPA548构成的5V恒压模块设计.................................64.3继电器构成的自动换挡测电阻模块..............................74.4电机驱动模块................................................84.5TFT触屏显示模块.............................................95软件设计.........................................................106系统测试.........................................................116.1100档位的测试..............................................116.21KΩ档位的测试.............................................116.310KΩ档位的测试............................................126.410MΩ档位的测试............................................127设计总结.........................................................13参考文献...........................................................14致谢..............................................................15附录附录1主要元器件清单附录2STM32F103ZET6小系统板原理图附录3单片机小系统板转接板PCB图附录4恒压源PCB图附录5产品实物图片简易自动电阻测试仪的硬...