Cheng Xinyi, Hu Kun, Shao Yiping
Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, TX 75391, USA.
IEEE Trans Nucl Sci. 2019 Sep;66(9):2107-2113. doi: 10.1109/tns.2019.2932270. Epub 2019 Jul 31.
We investigated a simple and effective method to extend 1-bit sigma-delta modulation (SDM) circuit based charge-to-digital converter (QDC) to read dual-polarity silicon photomultiplier (SiPM) output signals. With the same QDC circuit but different voltage biases to the circuit components, the new circuit can read and process both positive and negative polarity signals. We conducted experimental studies to validate its ability to read and process dual-polarity signals and evaluated its performance for Positron Emission Tomography (PET) detector applications. The results, based on energy, coincidence timing and crystal identification measurements, show that the circuit provides equal electronics capability for readout of both polarity signals and good performance for SiPM array-based PET imaging detector applications. Overall, the dual-polarity QDC readout electronics can be easily implemented to extend the range of signal polarity and to provide effective and flexible detector front-end electronics for reading single- or dual-polarity SiPM output signals.
我们研究了一种简单有效的方法，将基于1位sigma-delta调制（SDM）电路的电荷数字转换器（QDC）扩展为读取双极性硅光电倍增管（SiPM）输出信号。使用相同的QDC电路，但对电路组件施加不同的电压偏置，新电路可以读取和处理正极性和负极性信号。我们进行了实验研究，以验证其读取和处理双极性信号的能力，并评估其在正电子发射断层扫描（PET）探测器应用中的性能。基于能量、符合定时和晶体识别测量的结果表明，该电路为读取两种极性信号提供了同等的电子能力，并且在基于SiPM阵列的PET成像探测器应用中表现良好。总体而言，双极性QDC读出电子设备可以轻松实现，以扩展信号极性范围，并为读取单极性或双极性SiPM输出信号提供有效且灵活的探测器前端电子设备。
