P4SMAJ28 is an SMD transient voltage suppressor diode designed for overvoltage and ESD protection in commercial and industrial applications. It features a standoff voltage (VWM) of 28 V with a peak pulse power dissipation of 400 W (10/1000 µs waveform) and a steady-state power dissipation of 1 W at 75°C. The device exhibits very fast response time and is available in both unidirectional and bidirectional versions in the SMA (DO-214AC) package. With a maximum forward voltage of 3.5 V at 25 A and thermal resistance of 70 K/W junction-to-ambient, the P4SMAJ28 provides reliable protection for sensitive electronic circuits against transient overvoltage events and electrostatic discharge.