Construction of a Fast Potentiostat

At the time of writing, the available commercial instruments do not allow for the full range of time scales for CV or DPS experiments. In particular, they are generally limited to less than l(X)0V/s or to time steps exceeding 1ms. Most likely this situation will soon change, as the utility of such experiments becomes apparent. Electrochemical instrumentation that can perform high speed experiments can be constructed rather simply and at relatively small cost. 

O As have large input resistance. In other words, no current is allowed to flow through the — or -t- inputs. 

OAs have a low output resistance. Large currents can be drawn from the 

Besides the voltage follower configuration, which we have mentioned, the current follower and voltage amplifier configurations are important in designing a potentiostatic circuit. 

To complete the picture, we must examine the working electrode. It is connected in a current follower mode so that current through the working electrode is shunted around op amp 3. In a feedback mode, the inputs are equal. 

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