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Presently a common characteristic trend in low and medium energy nuclear physics is to develop more complex detector systems to form multi-detector arrays. The main objective of such an elaborated set-up is to obtain comprehensive information about the products of all reactions. State-of-art γ-ray spectroscopy requires nowadays the use of large arrays of HPGe detectors often coupled with anti-Compton active shielding to reduce the ambient background. In view of this complexity, the front-end electronics must provide precise information about energy, time and possibly pulse shape. The large multiplicity of the detection system requires the capability to process the multitude of signals from many detectors, fast processing and very high throughput of more that 106 data words/sec. The possibility to handle such a complex system using traditional analogue electronics has shown rapidly its limitation due, first of all, to the non negligible cost per channel and, moreover, to the signal degradation associated to complex analogue path. Nowadays, digital pulse processing systems are available, with performances, in terms of timing and energy resolution, equal when not better than the corresponding analogue ones for a fraction of the cost per channel. The presented system uses a combination of a 15-bit 100 MS/s digitizer with a PowerPC-based VME single board computer. Real-time processing algorithms have been developed to handle total event rates of more than 1 MHz, providing on-line display for single and coincidence events.
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