SMCJ28A-Q is a transient voltage suppressor diode designed for surge and ESD protection in automotive and industrial applications. It features a surface-mount SMC (DO-214AB) package with a standoff voltage of 28V and peak power dissipation of 1500 watts, providing fast response times of less than 1.0 picosecond from 0V to breakdown voltage. The device is RoHS compliant and AEC-Q101 automotive grade certified, ensuring reliability in harsh environments. It is commonly used for protection of power buses, I/O interfaces, and overvoltage transient protection in telecom, computer, industrial, and consumer electronics applications.