Fast-locking phase-locked loop and associated fast-locking method thereof

摘要

A fast-locking phase-locked loop (PLL) and an associated fast-locking method thereof are provided. The fast-locking PLL may include a gear-shifting loop filter, which is configured to have a dynamic bandwidth. The gear-shifting loop filter may include a resistor set and a capacitor set coupled to the resistor set, where the resistor set is configured to have a dynamic resistance, and the capacitor set is configured to have a dynamic capacitance. More particularly, the dynamic resistance is switched from a first resistance to a second resistance and the dynamic capacitance is switched from a first capacitance to a second capacitance, to make the dynamic bandwidth be switched from a first bandwidth to a second bandwidth.