Soft failures in integrated circuits as a matter of ESD events

Due to ESD events in powered ICs “soft failures” could occur in the input/output cells of the padframe or in the IC core itself. As shown in this paper, soft failures can occur despite corresponding standard ESD protective structures. In order to detect these disturbances and to distinguish between valid signal changes and bit errors, a corresponding digital detector with adjusted switching thresholds is presented. Since the detector cell is correspondingly small (150μm × 16.5μm), it can be placed several times in the IC and read out via a scan chain.