The adaptive filters has been traditional developed in digital environment which involves several and large, computations time to get the coefficients that make the desired approximation. Most of the times, this calculations required a great capacity machines and there is no practical for some applications like channel equalization in cellular systems. This article shows an alternative way to develop adaptive filter using Low-Pass function and applying the LMS algorithm to reduce the error between the desired signal and the approximation and an application of this filter in a Decision Feedback Equalizer.