Design of a Programmable Gain Waveform Digitization Instrument for Detector Calibration

TL;DR

This paper presents a versatile calibration instrument combining a programmable gain pre-amplifier and a high-speed, high-resolution digitizer for detector calibration in physics experiments, capable of capturing detailed waveform information.

Contribution

It introduces a novel, integrated waveform digitization instrument with adjustable gain and high sampling rate, enhancing detector calibration accuracy and flexibility.

Findings

Bandwidth from DC to 450 MHz achieved

Effective number of bits (ENOB) exceeds 7 in high gain

Suitable for broad detector calibration applications

Abstract

To test and calibrate various detectors in nuclear and high energy physics experiments, a general purposed calibration instrument has been developed. All information including timing, amplitude and charge of signals can be directly obtained to calibrate detector with this instrument by amplifying and digitizing the signal waveform. The system consists of two parts, a large dynamic range pre-amplifier module and a high speed and high-resolution digitization module. The pre-amplifier module based on programmable gain amplifier and attenuator achieves gain from -26.2 dB to 24.4 dB, making it suitable to adapt to different detectors. Taking advantage of high speed and high-resolution analog-to-digit converter (ADC), the waveform digitization module samples the signal after conditioning with 12 bits resolution and up to 3.6 giga hertz samples per second (GSPS). To evaluate the feature of this instrument, an electronics testbench platform was installed and test results showed a bandwidth from direct current (DC) to 450 MHz and the effective number of bits (ENOB) is above 7 bits in high gain set and 5.8 bits in low gain set in the bandwidth range, which indicated that it had broad application prospect in detector calibration.