Abstract
This work presents an off-line Built -In Self-Test for timing systems based on synchronous BCD counters. We adopt for this case study a functional approach, exploiting the functional characteristics of the modules in the system for test pattern generation. Different alternatives for test sequences, simulation and experimental results are shown. Fault coverage of 95% and 100% are obtained under different test sequences. The test time scales up linearly with the number of cascaded counters, and the hardware overhead becomes less significant as the number of counters increases.