Research On Data Acquisition System Of Laser Particle Size Analyzer

Particle and particle size measurement is closely related to the life and production.According to Mie scattering theory and the combination of spectrum measurement methods,on the basis of the developed laser particle size analyzer prototype,data acquisition hardware system is produced.The photoelectric conversion of Laser particle size analyzer combination photoelectric receptor,I/V conversion,A/D conversion is finished under the control of the MCU.Data is transmitted and processed by communicating with PC.Computer program is written based on Keil uVision4.Communication is achieved using serial debugging assistant software.At last,the feasibility of the system is verified through experiments.The main tasks done are as follows.1.According to the scattering theory,on the basis of the principle of laser particle size analyzer and special photoelectric detectors characteristic parameter,33 channels parallel data acquisition hardware circuit is designed.Key components such as MCU,which is designed of tightly packaged and patch-typed;ADS7953,which is integrated with gating of multiplexer and A/D conversion;precision amplifier are chosen,the feasibility of the scheme is demonstrated by the parameter calculation.2.According to the principle of photoelectric conversion and data acquisition,hardware circuit schematics and PCB are designed.Hardware welding is completed.Achieving photoelectric signal data acquisition of common anode and common cathode.3.Debugging the developed circuit boards.Lower computer program is written.By using the serial port debugging assistant to achieve the communication of upper and lower computer.By using the photoelectric detectors to debug 33 channels signal acquisition module of circuit board successively.In addition,these experiments achieve the desired effect.