Abstract: An improved system and method for determining the lock condition of a Phase Locked Loop (PLL) is described. The lock detect circuit generates a fast lock detect signal that may be used to detect a transient loss of lock. The lock detect circuit may also include a phase alignment detect circuit to detect a misalignment in the phase of a reference clock and a feedback clock. Additionally, the lock detect circuit may include a reference clock detect circuit to detect if the reference clock signal is detected. Output signals from all of the above circuits may be communicated to a logic circuit in order to create an enhanced lock detect signal. An extended lock detect signal may also be communicated to the logic circuit.