Abstract: This paper presents a novel adaptive-bandwidth charge pump PLL with low jitter and a wide tuning range.With an adaptive bandwidth,the proposed PLL can scale its loop dynamics proportional to the output frequency and maintain optimal performance over its entire output range.In order to improve the jitter performance of the PLL,a matching technique is employed in the charge pump,and a voltage-to-voltage converter is used to achieve a low gain VCO.The experimental chip was fabricated in a 0.35μm CMOS process.The measured results show that the PLL has perfect jitter performance within its operating range from 200MHz to 1.1GHz.

Key words: PLL, adaptive bandwidth, low jitter, wide tuning range