Compact and Fast-Response Voltage Clamp for Bi-Directional Signal Swing Interface Applications

A compact bi-directional blocking voltage protection clamp with low overshoot voltage and high current handling capability is proposed. Under a high-stress 15-A very fast transmission line pulse, the initial overshoot voltage of the proposed structure is reduced to <80 V. The voltage is clamped below 20 V (safe operation voltage) within 2 ns. This allows for a fast turn-on speed to protect interface circuits in system-on-a-chip applications with a narrow electrostatic discharge design window.