An electrostatic discharge protection circuit comprises a comparator coupled between a power supply terminal and ground. The comparator responds to an electrostatic discharge event producing a trigger signal at a comparator output. The comparator comprises a first and second current mirror. The first and second current mirrors each comprise a sense device and a mirror device. The mirror devices are coupled in series between the power supply terminal and ground. The first mirror device produces an incident current and the second mirror device receives an absorption current. With a supply voltage on the power supply terminal equal to or greater than a trigger supply voltage, the absorption current exceeds the incident current and produces a trigger signal at the comparator output. The trigger signal activates a shunt device that shunts current from the power supply terminal to ground.