高速ADC多道能谱测井仪的道宽稳定方法

Reducing DNL of Fast ADC for High Resolution Energy Spectral Log Instrument

多运能谱测井仪是高分辨能谱测井和元素测井的重要仪器。通用高速ADC用于多道脉冲变换时降低仪器成本，减少分析死时间，提高测量效率。使用通用高速ADC时若不对其进行改进全运成多运能谱仪的道宽严重不一致，变化量可达50％～150％，能借明显失真。通过分析通用高速ADC引起的道还变化原因，及所阐述的实时向上或向下均遭的原理和方法稳定道宽，脉冲转换时间小于1～3μs，道宽变化减小到1％左右，为多道能谱测井仅使用通用高速ADC提供了重要的改进方法。

This paper describes commercial fast ADC application in the high resolution Gamma-ray energy spec-trum logging instrument. The commercial ADC has a lower cast ratio. But there are also serious DNL at-taining 50~150% to cause spectrum shape for the instrument. In this paper a new sliding scale averagingscheme was presented. By this scheme the upwards and downwards averaging in data circuit realtime pro-cess are permitted and the DNL reduced to 1%. This is important for high resolution gamma-ray energyspectral logging.