The ALTRO chip: a 16-channel A/D converter and digital processor for gas detectors
The ALTRO chip: a 16-channel A/D converter and digital processor for gas detectors
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DOI：
10.1109/nssmic.2002.1239377
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发表时间：
2002-11
期刊：
影响因子：
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通讯作者：
R. E. Bosch;A. J. D. Parga;B. Mota;L. Musa
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文献类型：
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作者：
R. E. Bosch;A. J. D. Parga;B. Mota;L. Musa
ALTRO (ALICE TPC Read Out) 芯片是一种混合信号集成电路，旨在成为气体探测器读出电子器件的构建模块之一。最初是为 CERN LHC 的 ALICE 实验的时间投影室 (TPC) 构思和优化的，其架构和可编程性使其适用于更广泛类别的气体探测器的读数。在一颗芯片中，来自 16 个通道的模拟信号被数字化、处理。压缩并存储在多采集存储器中。芯片中嵌入的模数转换器具有 10 位动态范围和 20 至 40 MHz 范围内的最大采样率。数字化后，流水线硬连线处理器能够从输入信号中消除各种系统和非系统扰动，这些扰动与轻型探测器的非理想行为、电子设备的温度变化、环境噪声等有关。处理器能够以 0.1% 的精度将脉冲峰值后的信号拖尾抑制在 1 /spl mu/s 之内，从而缩小脉冲以提高其识别能力。然后，通过删除低于可编程阈值的所有数据来压缩信号，每个峰值周围指定数量的前后样本除外。这会产生非零数据包。最终，每个数据包都标有时间戳和大小，以便随后可以重建原始数据并将其存储在读出带宽为 300 Mbyte/sec 的精简型多采集存储器中。本文讨论了 lite 实现的数字功能的算法以及 ALTRO 芯片在测量数据上的性能。
The ALTRO (ALICE TPC Read Out) chip is a mixed-signal integrated circuit designed to be one of the building blocks of the readout electronics for gas detectors. Originally conceived and optimised for the Time Projection Chamber (TPC) of the ALICE experiment at the CERN LHC, its architecture and programmability makes it suitable for the readout of a wider class of gas detectors. In one single chip, the analogue signals from 16 channels are digitised, processed. compressed and stored in a multi-acquisition memory. The Analogue-to-Digital converters embedded in the chip have a 10-bit dynamic range and a maximum sampling rate in the range of 20 to 40 MHz. After digitisation, a pipelined hardwired processor is able to remove from the input signal a wide range of systematic and non- systematic perturbations, related to the non-ideal behaviour of lite detector, temperature variation of the electronics, environmental noise, etc. Moreover. the processor is able to suppress the signal tail within 1 /spl mu/s after the pulse peak with 0.1% accuracy thus narrowing the pulses to improve their identification. The signal is then compressed by removing all data below a programmable threshold, except for a specified number of pre- and post-samples around each peak. This produces non-zero data packets. Eventually, each data packet is marked with its time stamp and size - so that the original data can be reconstructed afterwards and stored in lite multi-acquisition memory that has a readout bandwidth of 300 Mbyte/sec. This paper addresses the algorithms of lite implemented digital functions and the performance of the ALTRO chip on measured data.