An apparatus includes a protection circuit electrically connected to first and second voltage domains. The protection circuit includes a first silicon-controlled rectifier (SCR) and a second SCR connected in anti-parallel configuration. The first SCR is configured to connect the first voltage domain and the second voltage domain based on detection of a first triggering condition. The second SCR is configured to connect the second voltage domain and the first voltage domain based on detection of a second triggering condition. The protection circuit is configured to isolate the first and second voltage domains without the triggering conditions.