基于MSP430的便携式水质毒性检测仪的设计

Design of portable water toxicity detector based on MSP430

为了在野外快速准确地测量水质毒性污染情况,设计了基于MSP430的便携式水质毒性检测仪。检测仪根据发光细菌毒性检测的原理和使用场合选用低功耗的CPU,待机功耗仅为0.8μA;传感器输入使用进口的光电倍增管和低失调电流的放大电路提高了仪器的精度;软件采用相对比较法,无需另外增加恒温电路和光路补偿电路即能避免被测样品因颜色、悬浮物对发光菌种亮度检测的误差。测试结果表明:该检测仪符合GB/T15441的要求,具有测试方法简单、误差小、成本低、使用方便、低功耗等特点,有广泛的市场前景。

In order to measure water quality of the toxic contamination quickly and accurately outdoors, a portable water toxicity MSP430-based detector was developed. The detector was designed with low-power CPU whose power consumption is only 0.8 μA according to the principles of the luminescent bacteria toxicity test and occasions of using. The accuracy of the instrument was improved by using imported photomultiplier tubes and low offset current amplifier in input circuit of sensor. It is able to avoid the errors of light-detection of the luminescent bacteria caused by color of the measured sample and the suspended solids without the additional thermostat and optical compensation circuits because the relative comparison method is used in the software design. Test results show that the detector meet the requirement of national standard GB/T 15441. It has the advantage of simple testing, small error, low cost, easy to use, low-power consumption and it has broad market prospects.