A wide range PLL for 64X speed CD-ROMs & 10X speed DVD-ROMs

Abstract

In this paper, we propose a wide range PLL (phase locked loop) for 64X speed CD-ROMs and 10X speed DVD-ROMs. In order to develop a PLL with a wide locking range we designed a dual loop scheme which consists of a frequency detection loop and phase detection loop. The PLL has a locking range of 75 MHz-370 MHz A new V-I converter and a differential delay cell are used in a 3-stage ring VCO to reduce jitters. In addition, we propose a new charge pump which has perfect current matching characteristics for sourcing/sinking currents. This new charge pump improves the phase offset that reduces the locking range of the PLL. Implemented in a 0.25 /spl mu/m, 1-poly 5-metal CMOS process. It occupies an active area of 1.8 mm*1.1 mm.