A phase-locked loop (PLL) is proposed for low-voltage applications. A new charge pump (CP) circuit, using gate switches affords low leakage current and high speed operation. A low-voltage voltage-controlled oscillator (LV-VCO) composed of 4-stage delay cells and a low-voltage segmented current mirror (LV-SCM) achieves low voltage-controlled oscillator gain (K(VCO)), a wide tuning range, and good linearity. A LV-SCM generates more current with small area by switching the body rather than the gate. The PLL is implemented in standard 90-nm CMOS with regular V(T) (RVT) devices. Its output jitter is 2.22 ps (rms), which is less than 0.5% of the output period. The phase noise is -87 dBc/Hz at 1-MHz offset from a 2.24-GHz center frequency. Total power dissipation at 2.24-GHz output frequency, and with 0.5-V power supply is 2.08 mW(excluding the buffers). The core area is 0.074 mm(2).
IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS I-REGULAR PAPERS