Design of High Precision Universal Hybrid Acquisition Circuit
REN Yongfeng
DU Ruonan
WANG Shuqing
Abstract：Aiming at the problems of inapplicability and low acquisition accuracy of data hybrid acquisition system,a hybrid acquisition system with high universality,acquisition and isolation acquisition is designed.Each board of the system is cascaded by inter board connectors to enhance universality and scalability.An isolation acquisition card is added on the basis of the original ac-quisition card.Isolation acquisition is to isolate the same and different input signals,different types of signals,signals to be collect-ed and analog switches.In terms of hardware,the acquisition is uniformly controlled by the main control card FPGA,and only one-level analog switch is used for gating.The linear optocoupler is used to isolate the signal to be collected from the analog switch,DC/DC provides different isolation power supplies,and the Digital Isolator isolates the control signal.These measures reduce the signal oscillation,reduce the layered value,and improve the acquisition accuracy.In terms of software,the coding rules of ROM ta-ble are improved,the hardware circuit is simplified,and the load pressure is released.Accurate sampling conversion is achieved by analyzing AD acquisition timing.The test shows that the acquisition accuracy of the design can meet the accuracy requirement of 3‰and has high application value.It has been adopted in engineering.
Keywords：hybrid acquisitionROM tablesignal oscillationlinear optocoupler
Publication Date：2023-10-20
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：6( 2282-2286,2350 )