A crystal-based digital ring oscillator

A 0.16 mW, 2.3 Volt multi-channel digitally controlled oscillator (MDCO) core is designed in a 0.6 micron CMOS process and its prototype design is mapped on an Altera FPGA that can be used for clock recovery applications. This architecture is suitable for digital wireless and cable transceivers that use different bands for transmit and receive modes. As crystal-based-delay cells control its dominant propagation delay, we have obtained a reduced phase-noise in comparison to recently published analog-based DCOs.