Digitized preamplifiers: a circuit structure for sliding-scale optimization of the ADC range

Abstract

This work deals with the digitization of chargepreamplifier waveforms obtained from X-ray and -ray sensors. We suggest that the well-known "sliding-scale correction" structure can be inserted into a negative-feedback control loop to cancel the signal walks brought about by event pileup, low-frequency disturbances, microphonism, and hum. Cancellation of the walks permits to use the full analog-to-digital converter (ADC) range for the signals, even in high event rate conditions. The signal distortion caused by such cancellation is then eliminated numerically by the sliding-scale mechanism. As a result an extended dynamic range is obtained. Using a 12-bit ADC we got two extra bits to accomodate the baseline walks and 1.14 to 1.43 extra bits on individual signals with 0.1 to 1 s rise time.

Using Analog-to-Digital Converter ADC1413D for high-resolution gamma-ray spectroscopy

“…the European Advanced Gamma Tracking Array detector, in the nuclear-physics measurement campaigns performed at LNL and GSI Laboratories [1]- [3]. Other more sophisticated cases in which an offset is introduced adaptively before conversion for performance optimization are also found in literature [4], [5]. In this work we study the relation between such an offset and the ADC noise, using Analog-to-Digital Converter ADC1413D [6] as installed in a DIGI-OPT12 digitizer card [7].…”

Open-source diagnostic tool with GUI for the new AGATA/GALILEO/EUCLIDES digitizer cards

“…N current and next generation nuclear phy employing segmented high-resolution detectors, like AGATA and GALILEO digitization of the preamplifier signals is a pre the shape of the preamplifier signals, inc frequency component, contains important info be used by digital-filtering algorithms for opt the pulse height, the occurrence time, the t position of the interaction points inside the d of the trajectory of the impinging particles parameters. Availability of fast, low-power flash ADC's (Analogue to Digital Conver optical links, and high capacity storage d possible to sample, transmit to a remote locat locally elaborate the entire preamplifier sig saving the mere pulse height as in traditional "Digi-Opt12" is a 12-channel digitizer card architectures and conceived for digital semiconductor detector signals [7]- [13]. A stacked Digi-Opt12 cards is shown in Fig.…”