is an X-ray fluorescence instrument for the analysis of materials:
Sinerlab and Nuclear Instruments developed a Digital Pulse Processor (DPP) with integrated 16k-Multichannel Analyzer ready to use for laboratory and OEM integration. The DPP-2570 Digital Pulse Processor can be used in applications requiring high resolution energy measurements like X-ray flourescence or X-ray spectroscopy. It works with all transistor reset detectors like Amptek SiPM XR-100CR or Moxtek XPIN. It integrates an analog shaper and amplifier, an HV voltage generator (up to 250V), programmable gain amplfier, 150 MSPS 14 bit ADC and FPGA based DPP algorithm.
The digitized signal is sent to a programmable decimator that enables the instrument to implement filters with a length up to 64 µs. The output of the decimation stage is then deconvolved by a three zeros digital deconvolutor circuit. An innovative algorithm automatically calculates the poles of the input signal to find the best zeros position on the z-plane. The deconvolved signal is split and sent to the triggering and processing units. The trigger circuit consists of a fast trapezoidal filter with discrimination. The signal is simultaneously processed by an energy filter with programmable trapezoidal shape that lasts from 40 ns to 40 µs. Pileup and saturation circuit are also implemented. The reference level (baseline) of the pulses is estimated and subtracted to the corresponding energy measure. The corrected energy values are collected in a histogram of 16k channels into the FPGA device. The FPGA is connected both to a microcontroller and to a USB interface. The microcontroller is devoted to managing the Ethernet LAN and WiFi.
The trapezoidal digital filter offer significantly enhanced throughputs and achieve energy resolutions comparable to analog systems. The DPP2570 has been tested with an Amptek SiPM 13mm XR-100CR detector. A Am241 source has been used to generate the following spectrum. The resolution on 13.95KeV peak is about 2%, that is comparable with the intrinsic detector resolution.