Importance

Loading Importance Indicators...

Abstract

Circuit configurations and related methods are disclosed that may be implemented to protect circuitry from adverse effects of transistor snapback that may occur during ESD events. The circuitry and methods may be implemented as part of distributed ESD rail clamping circuitry that includes ESD circuit elements that are coupled to power nodes or supply rails and not to signal nodes or signal pads of the circuitry in a manner that reduces parasitic loading on signal pads to reduce or substantially eliminate NMOS and/or PMOS transistor snapback occurrence, while at the same time providing rail-clamping capability during occurrence of ESD events. Using the disclosed circuitry and methods, at least a portion of ESD current may be diverted by clamp circuitry from or to a supply rail to reduce voltage differential across the sources of CMOS output transistors relative to their bulk terminals in a manner that reduces forward biasing of parasitic BJTs present at each of the CMOS output transistors, thus reducing or substantially eliminating occurrence of transistor snapback during an ESD event.

Loading the Abstract Image...

First Claim