CHARGE-SENSITIVE AMPLIFIER FRONT-END WITH AN NJFET AND A FORWARD-BIASED RESET DIODE

A new configuration of a resistorless charge sensitive preamplifier wi th an nJFET as an input device was tested, The de level of the input o f the amplifier was kept constant by a slightly forward-biased np junc tion connected between the input of the amplifier and ground, A noise level of 22 root mean square (r.m.s,) electrons is measured at 295 K a nd 15 r,m,s, electrons at 253 K. The dynamic behavior of the amplifier is investigated with different leakage current conditions. The techno logical benefits and the suitability of the front-end connection for r oom temperature detectors, particularly multianode drift chambers, are highlighted.