Multichannel monolithic front-end system design Part I. Peculiarities of the monolithic transistor application in head stages. Construction and operation mode optimization

In this work we discuss the features of BJT-JFET monolithic multichannel front-end ICs to be used in detectors of high energy physics. The noise calculation method has been developed for charge-sensitive preamplifiers (CSP), taking into account series terminal resistances, the dependence of fT on the BJT operation point, and stray capacitances. The method makes it possible to investigate separate ENC components produced by various noise sources and to work out the recommendations to optimize the input transistorʹs structure and performance as well as the total CSP circuit.