The present invention relates to a conversion device, or commonly called transimpedance amplifier, able to convert an input electric current (Id) from a current source such as a photonic sensor (D) into an output voltage (Vo) and comprising an integrated electronic circuit comprising, inter alia, a resistive component (Rf) of adjustable value and a capacitive component (Cf) of adjustable value. The invention also relates to a method for determining the values of the resistive component and of the capacitive component.