Working 225 V Over-Voltage Protection Cell With Tunable Trigger and Holding Voltages for Latch-Up Immunity

This paper describes the challenges encountered and solutions found to be the problem of developing over-voltage protection for 225 V circuit applications with measured tunable trigger voltages of 100-300 V, measured tunable holding voltages for latch-up immunity of 50-240 V, and corresponding strengths of 8.0-2.4 A Transmission Line Pulse (TLP). The device is engineered using technical computer-aided design and the performance is measured with dc characterization, unpowered TLP, powered and unpowered Electrostatic Discharge (ESD), as well as a 225 V product placement with a 1500-h High Temperature Operating Life lifetime reliability monitor. The final cell enables both 225 V powered and unpowered protection from high voltage switching transients and ESD events.