A sensor for on-chip monitoring the effects of operating conditions on a circuit, Integrated Circuit (IC) chips including the sensors, and a method of monitoring operating condition effects on-chip circuits, e.g., for the occurrence of electromigration. The sensor includes a multi-fingered driver associated with a monitored circuit, sensitive to known circuit parameter sensitivities. Sense and control logic circuit selectively driving the multi-fingered driver, and selectively monitoring for an expected multi-fingered driver response.