This paper introduces a low-cost technique for SNR estimation of analog signals based on digital ATE acquisition. The idea is to use the comparator available in standard digital test channel to record level-crossing events and to apply post-processing in order to retrieve analog signal characteristics. In this paper, we develop an analytical expression that relates the signal SNR to the distribution of level-crossing events distribution. Validations demonstrate that accurate SNR estimation can be achieved under different conditions of signal and ATE capture parameters.