In an integrated circuit device requiring electrostatic discharge (ESD) protection, a circuit is added between a power supply bus and a ground supply bus to shunt the ESD event current and thereby avoiding damage to the device. Specifically, the circuit uses bipolar junction transistors of the PNP type...http://www.google.com/patents/US6400540?utm_source=gb-gplus-sharePatent US6400540 - Clamp circuit to prevent ESD damage to an integrated circuit
