US Patent 10332871 Area-efficient and robust electrostatic discharge circuit

Described is an apparatus which comprises: a pad; a first transistor coupled in series with a second transistor and coupled to the pad; and a self-biasing circuit to bias the first transistor such that the first transistor is to be weakly biased during an electrostatic discharge (ESD) event. Described is also an apparatus which comprises: a first transistor; and a first local ballast resistor formed of a trench contact (TCN) layer, the first local ballast resistor having a first terminal coupled to either the drain or source terminal of the first transistor.