Medipix2:: a 64-k pixel readout chip with 55 μm square elements working in single photon counting mode
Medipix2:: a 64-k pixel readout chip with 55 μm square elements working in single photon counting mode
复制标题
DOI：
10.1109/tns.2002.803788
复制
发表时间：
2002-10-01
影响因子：
1.8
通讯作者：
Pemigotti, E
中科院分区：
文献类型：
--
作者：
Llopart, X;Campbell, M;Pemigotti, E
Medipix 2芯片是一种像素探测器读出芯片，由256 x 256个相同的元件组成，每个元件都以单光子计数模式工作，用于正或负输入电荷信号。每个像素单元包含大约500个晶体管，并且占据55 μ m × 55 μ m的总表面积。一个20微米宽的八角形开口连接检测器和通过凸点焊接的输入端。该反馈提供逐像素地对检测器漏电流的补偿。两个相同的脉冲高度鉴别器用于创建一个脉冲，如果脉冲输出福尔斯落在一个定义的能量窗口。然后用13-B伪随机计数器对这些数字脉冲进行计数。基于移位寄存器的计数器逻辑也充当像素的输入输出寄存器。每个单元还具有一个8-B配置寄存器，可对每个寄存器进行屏蔽、测试使能和3-B单独阈值调整。该芯片可以配置为串行模式，并以串行或并行方式读出。该芯片的设计和制造在6金属0.25妈妈CMOS技术。第一次测量显示140 e（-）均方根（rms）的电子像素噪声和360 e（-）rms左右的未经调整的阈值变化。
The Medipix2 chip is a pixel-detector readout chip consisting of 256 x 256 identical elements, each working in single photon counting mode for positive or negative input charge signals. Each pixel cell contains around 500 transistors and occupies a total surface area of 55 mum x 55 mum. A 20-mum wide octagonal opening connects the detector and the preamplifier input via bump bonding. The preamplifier feedback provides compensation for detector leakage current on a pixel by pixel basis. Two identical pulse height discriminators are used to create a pulse if the preamplifier output falls within a defined energy window. These digital pulses are then counted with a 13-b pseudorandom counter. The counter logic, based in a shift register, also behaves as the input-output register for the pixel. Each cell also has an 8-b configuration register which allows masking, test-enabling and 3-b individual threshold adjust for each discriminator. The chip can be configured in serial mode and readout either serially or in parallel. The chip is designed and manufactured in a 6-metal 0.25-mum CMOS technology. First measurements show an electronic pixel noise of 140 e(-) root mean square (rms) and an unadjusted threshold variation around 360 e(-) rms.