A low-noise preamplifier-filter system

Abstract The behaviour of an amplifier-filter circuit for low-noise measurements composed of a charge-sensitive preamplifier, an RC differentiator and a bridged-T integrator, has been studied. The signal and noise characteristics have been derived from the impulse response function, the latter has been calculated by application of the Laplace transform technique. Signal and noise functions are given in analytical form, while graphical presentations of the output characteristics illustrate their dependence on the parameters of the amplifier system.