Designed to protect telecommunication systems from dangerous transients conducted through transmission lines, the surface-mount SGT Series of SCR thyristors provides bi-directional overvoltage and lightning protection. The devices are manufactured in a double-diffused silicon thyristor technology and offer voltage clamping from two directions in a single chip.The thyristors turn on in less than 1 ns with a low clamping voltage (as low as 80V), even during fast-rising transient pulses. Their low-profile SMT packaging allows individual placement of devices on line cards or in other locations that offer little headroom, such as PCMCIA cards.In addition to their speedy transient response, the SGT Series thyristors offer high transient current capability and an automatic reset function with low shunt capacitance. Nine parts range in standoff voltages from 65V to 300V are available. Peak pulse transient current ratings are 100A.