The transient behaviour of an input protection

The high frequency behaviour of input protections has been measured with electro-optic sampling. These measurements allow the determination of the time dependence of the voltages at internal nodes as well as the time dependence of the current through the input protection. Simulations are performed using a detailed model of the input protection and a simplified model of the integrated circuit, including connections. The measurements are vital to the development of the model, which ultimately aims at explaining the differences found in Human Body Model testing and Charged Device Model testing.