一入三出智能信号电流分配器设计.docx

摘 要4-20mA是标准电流信号，工业上一般用的仪器仪表的信号电流都是4-20mA，即指最小电流为4mA，最大电流为20mA。在应用中若使用电压传输时，会有噪声、压降等影响，为了解决此类问题的影响，我们用电流来传输信号，因为电流对噪声并不敏感。4～20mA的电流环便是用4mA表示零信号，用20mA表示信号的满刻度，而低于4mA高于20mA的信号用于其故障的报警。本设计以AT89C52单片机为核心，通过ADC0832数模转换器进行采样，LED显示电路进行大小的显示，MAX517数模转换器进行输出，并通过放大电路对信号进行放大输出，以达到三路输出的目的。同时有告警电路对使用者进行提醒。为保证输出之间不受影响，三路输出之间为电气隔离的。并设计软件以实现所需的功能。经过调试，最后验证本设计实现了以上所提到的功能，具有一定的创新性和使用价值。本设计系统可以实现对一路信号的输入转化为三路的输出，可实现对多路数据的采集。可与各种工业传感器配合，取回参数信号，隔离变送传输。已经实现了对多路信号的检测、监控。 关键字：单片机，AD模数转化器，DA数模转换器，放大器ABSTRACT4-20mA standard current signal, industrial instrumentation on the general use of signal current is 4-20mA, referring to the minimum current of 4mA, a maximum current of 20mA. If used in the application of the voltage transfer, there will be noise, pressure drop and other effects, in order to solve such problems impact, we use electric current to transmit the signal, because the current is not sensitive to noise. 4-20mA current loop is to use that 4mA zero signal, the signal with a 20mA full-scale, higher and lower than 4mA 20mA signal for the failure of the police.The design AT89C52 microcontroller as the core, through the digital to analog converter ADC0808 sampling, LED display shows the size of the circuit, DAC0832 digital to analog converter for output, And in order to achieve the purpose of three outputs, through the amplifier circuit amplifies the signal output. At the same time there is an alarm to remind the user circuit. To ensure that between the output is not affected, for the three-way electrical isolation between the outputs. And the design software to achieve the desired functionality. After commissioning, the final validation of the design and implementation of the above mentioned features, with some innovative and value in use.The design of the system can be achieved on one way the input signal into a three-way output, can realize the multi-channel data acquisition. Match with a variety of industrial sensors, retrieve parameter signal isolation transmitter transmission. H