Driving an enable pin to its required logic level allows a circuit block, regulator, or integrated circuit to turn on and perform its function. When not enabled, the device typically enters a low-power standby mode or places its outputs into a high-impedance state. It is a fundamental method for power sequencing and bus management in digital electronics.
Heard on the job
You need to pull the regulator's enable pin high before the processor will get any core voltage.