Amplifiers dedicated for large area SiC photodiodes

Referat co-authors: Piotr Doroz, Mariusz Duk, Michal Borecki.

Large area SiC photodiodes find applications in optoelectronic sensors working at special conditions. These conditions include detection of UV radiation in harsh environment. Moreover mentioned sensors have to be selective and resistant to unwanted signals, therefore the modulation of light is used and the rejection of constant current component of signal. The popular frequency used in such sensor is 1kHz. The large area photodiodes are characterized by large capacitance that varies with polarization of photodiode and can significantly modified conditions of signal pre-amplification. The two pre-amplifiers circuits topology are analyzed: transimpedance amplifier and not inverting voltage to voltage amplifier with negative feedback. The feedbacks of both pre-amplifiers are equipped with elements used for initial constant current signal rejection. Both circuits are analyzed with simulation and experimental approach.