P4SMAJ170 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 170 V with a breakdown voltage (VBR) of 178 V, and delivers a peak pulse power dissipation of 400 W at a 10/1000 µs waveform. The device operates with a maximum steady-state power dissipation of 1 W at 75°C and exhibits very fast response time for transient suppression. With a junction temperature range of -50°C to +150°C and thermal resistance of 70 K/W (junction to ambient), the P4SMAJ170 is ideal for protecting sensitive circuits against voltage spikes in power supplies, communication lines, and industrial control systems.