The J-V characteristics of an illuminated solar cell can be represented as a simple explicit form of v(eta) + j(xi) = 1, here the normalized voltage, v and normalized current density j can be represented as v = V/V-oc and j = J/J(sc) respectively, where V-oc is the open circuit voltage and J(sc) is the short circuit current density. Here eta and xi are the shape parameters of the J-V curve which can be obtained from the experimental data. In this paper it is shown that the model parameters, eta and xi can be used for the analytical representation of the single exponential model parameters of an illuminated solar cell, namely ideality factor n, parasitic series resistance R-s, parasitic shunt resistance R-sh, dark-current density J(0), and photo-generated current density J(ph). The simple measurement of voltage (V) and corresponding current density (J) of an illuminated solar cell experimentally determines the parameters eta and xi with which the physical parameters of the illuminated solar cells can be determined. The proposed analytical expression is used to determine the physical parameters for wide variety of solar cells and gives satisfactory results. (C) 2012 Elsevier Ltd. All rights reserved.