An MVT based all-digital DAQ for energy determination

Traditional energy determination methods with shaper circuits are not suitable for high count rates applications, for which the analog-to-digital converters (ADC) with very high sampling rate are often used to digitize the pulse signal directly. The high sampling rate ADC brings the problems of high power consumption, high data bandwidth, and less stability and so on. In this paper, an all-digital data acquisition system (DAQ) for energy determination based on multi-voltage thresholds (MVT) technique is proposed to achieve high energy resolution and process pile-ups without using ADC. An energy resolution (ER) of 5.9% at 511 keY is obtained with a LaBr3/PMT detector, which is equivalent to that of a 750 MSPS ADC. With pile-up processing for a LYSOIPMT detector, the MVT based DAQ recovered 8% more singles with an energy windows of 400-600 keY and improved the energy resolution from 27.3% at 511 keY to 20.5% at 511 keY. The promising results demonstrated the potential of the all-digital MVT based DAQ for energy determination in high count rate and high resolution radiation detection.