The SM8S15A is an unidirectional transil diode (TVS), which is a type of voltage-sensitive, solid-state protection device used to suppress transient overvoltages. It is manufactured by Yint, and is designed to protect sensitive electronic components from electrostatic discharge (ESD) or transient voltage surges. This TVS has a maximum voltage (breakdown) of 6600W, and a maximum peak pulse current of 270A. It has a unidirectional, bidirectional, or positive-only level-dependent triggering voltage range of 16.7-18.5V, as well as a maximum operating voltage of 24.4V. Finally, the device has an average clamping current of 10uA and is ROHS compliant.