In the paper a new method of Random Telegraph Signal (RTS) noise identification is presented. The method is based on a standardized histogram of instantaneous noise values and processing by Gram-Charlier series. To find a device generating RTS noise by the presented method one should count the number of significant coefficients of the Gram-Charlier series. This would allow to recognize the type of noise. There is always one (first) significant coefficient (c0) representing Gaussian noise. If additional coefficients cr (where r > 0) appear it means that RTS noise (two-level as well as multiple-level) is detected. The coefficient representing the Gaussian component always has the highest value of all. The application of this method will be presented on the example of four devices, each with different noise (pure Gaussian noise signal, noise signal with two-level RTS noise, noise signal with three-level RTS noise and noise signal with not precisely visible occurrence of RTS noise).
The course of design of an optocoupler's PSpice macromodel including noise sources is described. The PSpice macromodel is proposed for the low frequency range. The PSpice model of a MOSFET transistor was applied as the noise source type 1/fα in an optocoupler PSpice macromodel. In the enhanced macromodel the value of an exponent α can be changed in the range of 0.8-1.25.