A phase-locked loop circuit comprises a multi-phase oscillator having a plurality of coupled oscillators. A calibration module detects mismatches between frequency characteristics of the different oscillators in the phase-locked loop circuit during a calibration process. The calibration module then calibrates the various oscillators to compensate for the detected mismatch. Once calibrated, the phase-locked loop circuit can operate with little or no performance degradation despite the mismatch in frequency characteristics between the different oscillators.