SP1053 & SP1054 Unidirectional Discrete TVS Littelfuse SP1053 & SP1054 Unidirectional Discrete TVS avalanche breakdown diodes are fabricated in a proprietary silicon avalanche technology and protect each I/O pin to provide a high level of protection for electronic equipment from electrostatic discharge (ESD). These robust diodes can safely absorb repetitive ESD strikes at ±30kV (contact discharge, IEC 61000-4-2) without performance degradation. Additionally, each diode can safely withstand 1.0A (SP1053) or 2.5A (SP1054) surge (8/20 waveshape as defined in IEC 61000-4-5 2nd edition) at a very low clamping voltage.