On the Equation i = i 0 [exp α (v − Ri) − 1]

In general, the current-voltage characteristic of a nonlinear resistive element can be represented by an exponential function: i = i0(eαe− 1), where i is the current through the nonlinear resistor, e is the voltage across the resistor, and i0and α are constants. In a circuit containing a linear resistor R in series with the nonlinear resistor, the characteristic becomes i = i0[eα(v−R i)− 1], where v is a series voltage source.