Design And Implementation Of Analog To Digital Conversion Module Based On PXI Bus

Analog-to-Digital Conversion is the core content of the data collection,that means,data collection is completed AD conversion process.With the development of current science and technology,data acquisition technology plays a more and more important role.A good performance,easy to use ADC module is more conducive to system integration,that is finished important work in large-scale comprehensive test system.This paper is mainly to design a analog-to-digital conversion module based on PXI bus.Using PXI 3 u board structure,integrated the module in the PXI system,finished high precision,low noise,portable design of real-time data acquisition card.The ADC module has a 100 KHZ sampling rate,64 channels parallel acquisition,witch is suitable for the multi-channel signal parallel sampling system at low speed.This ADC module uses FPGA as the core controller,In order to make communication with PCI bus,the FPGA+PCI9054 may be a good ideal.Meanwhile,taking advantage of PXI trigger functions.Under the control of the upper machine,the relevant configuration and control information acquisition signal transmission to the PCI9054 through PCI bus.After completed the communication between FPGA and PCI bus,then,the FPGA should control complete with PCI9054 local bus communication.When the FPGA receives the relevant control information,and transfer this control information to the analog switch circuit.The gain control information will be sent to the program-controlled amplifier.Will control the ADC sampling information sent to the control of AD7663 and read back to transform data.Finally the data through PCI bus back to the computer,then display and analysis functions performed by a computer.Moreover,this PXI board can control the multichannel parallel or single channel sampling,can be a single acquisition or continuous acquisition.The maximum sampling rate is 100 kHz,that means the secend sampling will begin after the last sampling.AD7663 will speend 4 ?s to complete a sampling,so that the sestem have plenty of time for data transmission after each sampling completed.This board test is mainly completed the dc measurement error test and test frequency measurement accuracy.Test results meet the requirements of performance indicators...