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Zhu C.,CAS Anhui Institute of Optics and Fine Mechanics | Zhu C.,Anhui Key Laboratory of Environment Optics and Technology | Liu J.,CAS Anhui Institute of Optics and Fine Mechanics | Liu J.,Anhui Key Laboratory of Environment Optics and Technology | And 6 more authors.
Yi Qi Yi Biao Xue Bao/Chinese Journal of Scientific Instrument | Year: 2010

In order to fulfill the requirements of high-speed, real-time data acquisition and large scale data storage during the development of aerodynamic particle sizer (APS), a dual-port RAM chip CY7C028 is used as the shared memory. The hardware interface circuits of the dual-port RAM, CPLD and MCU, and the software flow are shown in this paper, which achieve high-speed and large-capacity communication between the CPLD and microcontroller, and effectively extract the information of aerodynamic particle diameter. The memory capacity is up to 32 768 channels and each one can count up to 65 635 particles, and the operation speed is in the order of nano-seconds. The dual-port memory has successfully applied in the APS and fully meets the requirements of speed and storage capacity in continuous, real-time and online monitoring. And the dual port RAM works very stable and reliable. Source

Li D.,CAS Anhui Institute of Optics and Fine Mechanics | Li D.,Anhui Key Laboratory of Environment Optics and Technology | Li D.,CAS Hefei Institutes of Physical Science | Liu J.,CAS Anhui Institute of Optics and Fine Mechanics | And 17 more authors.
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2014

Because of its aerodynamic diameter of the aerosol particles are stranded in different parts of different human respiratory system, thus affecting human health. Therefore, how to continue to effectively monitor the aerosol particles become increasingly concerned about. Use flight time of aerosol particle beam spectroscopy of atmospheric aerosol particle size distribution is the typical method for monitoring atmospheric aerosol particle size and particle concentration measurement, and it is the key point to accurate measurement of aerosol particle size spectra that measurement of aerosol particle flight time. In order to achieve accurate measurements of aerosol particles in time-of-flight, this paper design an ECL-TTL high-speed timer with ECL counter and TTL counter. The high-speed timer includes a clock generation, high-speed timer and the control module. Clock Generation Module using a crystal plus multiplier design ideas, take advantage of the stability of the crystal to provide a stable 500MHz clock signal is high counter. High count module design using ECL and TTL counter mix design, timing accuracy while effectively maintaining, expanding the timing range, and simplifies circuit design. High-speed counter control module controls high-speed counter start, stop and reset timely based on aerosol particles time-of-flight, is a key part of the high-speed counting. The high-speed counting resolution of 4ns, the full scale of 4096ns, has been successfully applied Aerodynamic Particle Sizer, to meet the precise measurement of aerosol particles time-of-flight. © 2014 SPIE. Source

Huang S.-H.,CAS Anhui Institute of Optics and Fine Mechanics | Huang S.-H.,Anhui Key Laboratory of Environment Optics and Technology | Liu J.-G.,CAS Anhui Institute of Optics and Fine Mechanics | Liu J.-G.,Anhui Key Laboratory of Environment Optics and Technology | And 16 more authors.
Guangxue Jingmi Gongcheng/Optics and Precision Engineering | Year: 2010

To characterize the size distribution of aerosol particles, a measuring simultaneously method for aerodynamic diameters and optic diameters of the aerosol particles is studied, and then the classifying count principle is described. Based on large-scale programmable logic chips and dual-port high-speed large-capacity memory chips, a high-speed and large-capacity classifying count storage for aerosol particles is designed by using a multi-channel storage technology. By combining with the functions of single pulse counters and characteristic signal classifying counters, the storage can offer the capacity up to 65 535 channels, each of which can count to 65535 particles with a operating speed up to 15 ns. The storage has a simple circuit, and its multiple channel circuits make only up of two MACH435 and two IDT7009 chips. The characteristics of aerosol particles with the sizes of 0.5~20 μm in air is counted, and the particle distribution spectra are obtained. As a key storage component of the aerodynamic particle sizer developed by our institute, this storage satisfies the requirements of the measurement in real time for the speed and capacity. Source

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