Abstract This paper presents Haar wavelet based method of analysis for observer design in the generalized state space or singular system of transistor circuits. The technique can be interpreted from the incremental and multiresolution view point. Accurate solutions can be obtained by changing the time scale ( m ) , at the same time the main features of the solution are preserved. It can be easily implemented with a digital computer and it is found to be fast, flexible, convenient and computationally attractive.