An electrostatic discharge (ESD) protection circuit in a semiconductor integrated circuit (IC) having protected circuitry. The ESD protection circuit includes a silicon controlled rectifier (SCR) having at least one first type high dopant region coupled to a first reference potential of the protected circuitry, and at least one second type high dopant region coupled to a second reference potential of the IC. The SCR is triggered by an external on-chip trigger device, which is adapted for injecting a trigger current into at least one gate of the SCR.