Patent ID: 8247839
Filing Date: 2012-08-21
Classification: H01L

Abstract:
1. An electrostatic discharge (ESD) protection circuit comprising: an SCR including at least a PNP transistor and at least a NPN transistor, said PNP transistor is coupled to an anode and the NPN transistor is coupled to a cathode; said PNP transistor including a PNP first base, a PNP first emitter and a PNP first collector; said NPN transistor including a NPN first base, a NPN first emitter and a NPN first collector; said PNP first emitter is coupled to the anode, the first PNP base is coupled to the NPN first collector, the PNP first collector is coupled to the NPN first base and the NPN first emitter is coupled to the cathode; said at least one of the PNP transistor and the NPN transistor having at least one second collector; and at least one control circuit coupled between the anode and the cathode, said at least one control circuit coupled to said at least one second collector to control holding voltage of the SCR.