A synthesis of ESD input protection scheme

Abstract

A synthesis of total effective input protection, consisting of primary and secondary protection devices, is presented here for advanced CMOS technologies. In particular, it is shown that for efficient protection the primary circuit needs to be a low trigger SCR and the secondary circuit needs to be either a diffusion resistor with avalanche suppression or even a polysilicon resistor. The latter scheme with the poly resistor is shown to give greater than 6 kV of reliable performance, which can be particularly attractive for analog circuit applications.