A circuit design of a cyclic voltage generator

Chourasia Ashish Bhupatprasad and Kelkar Deepali Shrikant

The present paper describes a simple circuit for construction of a cyclic voltage generator, which can be used in electrochemical synthesis of conducting polymer films like polyaniline(PANI), polythiophene, polypyrrol etc. The circuit consists of a clock generator; its frequency is converted into digital voltage which is further converted to analog form using digital to analog converter (DAC). This analog voltage, after boosting, is used as a source of voltage in the synthesis of conducting polymer. Since the oxidation potential for a polymer is unknown, the circuit developed has a facility to change output in cyclic fashion from initial to final value at a rate of 45 mV/s and return back to the initial position. The designed circuit can also hold the potential at any desired value and hence can also be used in the potentiostatic configuration as a potentiostat for synthesizing a conducting polymer.

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