A circuit design of a cyclic voltage generator

Authors: 

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.

[1] Bacon J. and Adams R.: J. Am. & Chem. Soc., 1968, 90, 6596.
[2]. MacDiarmaid A., Chiang J., Huagg W. et al.: Mol. Cryst. Liq. Cryst., 1985, 125, 309.
[3] Sinha U., Bandyopadhyay B., Roy R. and Sen S.: Indian J. Pure and Appl. Phys., 1999, 37, 921.
[4] Gaykwad R.: Operational Amplifiers and Linear ICs, 4th ed., Prentice Hall of India 2000.
[5] Horowitz P. and Winfield H.: The Art of Electronics, 2nd ed., Cambridge University Press. 
[6] Diaz A. and Logan J.: J. Electronal Chem., 1980, 111, 111.
[7] Chowdhury P. and Saha B.: Indian J. Chem. Tech., 2005, 12, 671.