A system on chip includes a debugging controller, a plurality of clusters, and a power management unit (PMU). The debugging controller is included in a first power domain and a joint test action group (JTAG) interface is included in the first power domain. Each of the clusters is included in at least second power domain different from the first power domain. The PMU is configured to release a powered-off state of the debugging controller in response to a debugging request signal output from the JTAG interface.