STS321240B301 is a bi-directional TVS diode ESD suppressor designed to protect single I/O lines from electrostatic discharge and transient overvoltage events. It features a reverse working voltage rating of 24 V, reverse breakdown voltage of 26.7 V (at 1 mA), and delivers 400 W peak pulse power dissipation on an 8/20 µs waveform. The device provides low clamping voltage (40 V at 1 A, 50 V at 8 A) and low reverse leakage current (1 µA maximum at 24 V), with junction capacitance of 30 pF typical. It meets IEC 61000-4-2 ESD protection standards up to ±30 kV (air and contact) and IEC 61000-4-5 lightning surge protection up to 22 A. This device is ideal for protecting microprocessor-based equipment, portable electronics, notebooks, desktops, servers, and cellular handsets from ESD damage.