Currently, some upcoming experiments plan to use the muon tagging systems based on the fast plastic scintillators with the readout via the wavelength shifter fibers and SiPM as the photo detector. The goal of these systems is to detect cosmic muons in the energy range from 0.1 to 1 GeV with high efficiency under high background counting rate. The paper describes the design of the custom electronics for the SiPM readout and signal processing we developed. The parameters of the analog and digital path were tested with 8 channels prototype. Our measurements reveal a good prototype performance. Achieved parameters satisfy the requirements of the experiments.