This document provides specifications for the ST04-27F1 SMD transient voltage suppressor diode made by Shindengen Electric Mfg. Co. Ltd. including maximum ratings, electrical characteristics, clamping voltage as a function of peak current and pulse width, reverse current as a function of junction temperature and applied voltage, breakdown voltage as a function of junction temperature, and junction capacitance as a function of applied voltage and frequency. Dimensions and a copyright notice are also included.