We propose an RLC model for PEDOT:PSS electrochemical transistors to interpret the persistent oscillating currents observed in experiments. The electrochemical reaction is represented by an inductor in the equivalent circuit. The simulation results show that an electrochemical device can be operated as normal transistors or oscillators under different voltage bias. This model predicts that analog circuit functions can be realized with "inductor-like" electrochemical devices. (c) 2011 Elsevier Ltd. All rights reserved.