A charge preamplifier for converting an electric charge generated in a charge source sensor into a voltage signal, including: a phase inverting amplifier including an input related to the charge source sensor, and an output for providing the voltage signal; a storage capacitor connected between the input and the output of the phase inverting amplifier; a reset system connected to the input of the phase inverting amplifier, for providing to the storage capacitor a discharging current as a function of a control signal, and a control element including: a first input connected to the output of the phase inverting amplifier, for withdrawing the voltage signal, a second input subjected to a reference voltage, a set of components configured and arranged to generate a control signal proportional to the deviation between the voltage signal and the reference voltage, the proportionality coefficient being lower than one in a high frequency band, an output connected to the reset system to provide thereto the control signal.