A Programmable Waveform Generator for Voltammetry

Abstract

ABSTRACT The voltammetric investigations of organic electrode reactions require a versatile waveform generator. Such a unit, to be used with a conventional potentiostat circuit, was constructed at modest cost using digital and linear integrated circuits. The basic design follows that of Myers and Shain [1], but its capabilities have been increased by using a 1600-Hz tuning fork clock and digital dividers to control hold times, differential comparators to sense preset voltage levels for logic control, and operational amplifiers to give first and second derivatives of the cell current. The output capabilities of this functjon generator are single and multiple triangular waves, ramps with variable holds at preset levels, and combinations of these modes. The initial and final voltages are selectable with either positive or negative voltage ramps. Scan rates with good linearity have been obtained over the range of 10 mV/sec to 100 V/sec.