An equivalent circuit model approach has been used to understand the influence of the DC bias on the physical behaviour of the peaks recently reported in the transient photoconductive (PC) decay curves of mercury cadmium telluride (HgCdTe) samples. This has resulted in an improved model, which provides more insight into the physical process responsible for the appearance of these peaks in the decay curves. Interpretation of the results and the effects of annealing on HgCdTe samples covered with anodic oxide are presented. (C) 2004 Elsevier B.V. All rights reserved.