Digital pulse processor using moving average technique

Abstract

A digital pulse processor with improved differential linearity and reduced dead time has been designed. The circuit uses an 8-b flash ADC (analog-to-digital converter) running at 36 MHz and continually sampling the signal from the preamplifier or shaping amplifier. The digitized signal is then processed by a digital moving averager. A digital peak detector is used for measuring the amplitude of the shaped pulses. A novel, threshold-free circuit has been designed that combines both the moving average and peak detection functions. The circuit also provides a timing signal with an uncertainty of one sampling period. The number of the averaged samples (equivalent to the shaping time constant) is digitally controlled. The resolution of the processor is limited by the finite ADC resolution and the finite sampling frequency. Increasing the sampling frequency should improve the resolution in pulse height analysis and the timing precision.<>