A detonator for initiating a detonation event in an explosive charge. The detonator comprises an exploding foil initiator and a switch. The exploding foil initiator includes a detonator bridge with a bridge member and a bridge contact that are electrically coupled to one another. The switch includes a switch contact that is spaced apart from the detonator bridge such that a spark gap of a predetermined width is defined between the bridge contact and the switch contact. A discharge arc, which is formed when a voltage in excess of a predetermined gap breakdown voltage is applied across the spark gap, closes the switch to thereby permit current to flow between the bridge contact and the switch contact.