Abstract

HERNANDEZ COLLADO, Alexei; IGLESIAS BENITEZ, Adrián; RODRIGUEZ PEREZ, Ángel  and  VAL, Osleidy. Transimpedance amplifier with programmable gain for multimodal plate reader. EAC [online]. 2017, vol.38, n.1, pp.17-32. ISSN 1815-5928.

This paper reports the main design elements of a programmable gain transimpedance amplifier (TIA) with a photodiode as sensor device. The photodiode and the TIA are part of the measurement system of a plate reader with two reading modes, absorbance and fluorescence. The photodiodes are one of the most used sensors in spectroscopy systems and TIA are fundamental for conditioning signals from such sensor block. An analysis of some aspects that must be considered in their design, such as bandwidth, gain, noise as well as the main sources of noise that affect their operation is done. An analysis of the stability of the system to ensure proper operation. Emphasis on the characteristics of the components used and detail some layout suggestions of printed circuit boards in order to minimize the leakage currents. The design presented is a novel and feasible alternative to maximize the dynamic range of measurement plate readers or other optical spectroscopy system designed and produced by the Cuban biopharmaceutical industry.

Keywords : TIA; gain; programmable; photodiode; noise; bandwidth; leakage currents.

        · abstract in Spanish     · text in Spanish     · Spanish ( pdf )