1. Veljko Radeka: Notes on the origin of charge amplifiers July2, 2014 1

2. The first record of a Charge-Sensitive Amplifier Circuit Classical “integrator” known from WWII (1941-5,) appears as charge amplifier in ~1950-ies (Gatti, et al.): Input capacitance ~ open-loop gain x C f 1948 Vacuum tube at the input until ~1963 when the first JFET is used … CfCf CfCf

3. The “last word” from vacuum tubes – introducing Ge detectors (Tavendale,1963) 3 Noise: ~200 e rms at 20pF, 1-2 μs The Cascode! Feedback Original charge preamp with JFET, 1968

4. From: V. Radeka “State of the art of low noise amplifiers for semiconductor radiation detectors” Proc. Intern. Symp. Nuclear electronics, vol. I (1968), p. 46.1, 28