LOW-NOISE POTENTIOSTAT FOR AMPEROMETRIC MEASUREMENTS IN MAGNETICALLY STIRRED SOLUTIONS

摘要

The invention relates to a low-noise potentiostat meant to be used for amperometric analyses in magnetically stirred solutions, using an electrochemical cell with three electrodes: an indicating electrode (WE), a reference electrode (RE) and an auxiliary electrode (CE). According to the invention, the potentiostat comprises an analogue circuit consisting of an operational circuit (OA) in a repeater mounting, with the role of taking over the steady voltage V, an operational circuit (OA) in amplifier mounting with negative reaction, with the role of providing a current Ineeded by the electrochemical cell and an operational circuit (OA) in a repeater mounting, with the role of applying the voltage Vto the cell with three electrodes, as well as a circuit processing the signal I, consisting of an instrumentation amplifier (INA) in trans-impedance mounting, the output voltage of which linearly depends on the cell signal and has a value sufficiently high for it to be read by an analogue-digital processing circuit of microcontroller type.