Self-aligned open-loop local quadrature phase generator

Abstract

A circuit architecture to generate differential CMOS quadrature (I/Q) local oscillator (LO) signals from a differential input at the same frequency is presented. The phase accuracy of the proposed architecture relies on the matching of two delays and linear phase interpolation. The feasibility of this approach is demonstrated by implementing an I/Q generator covering the operating frequency range from 1 GHz to 2.6 GHz, manufactured in a 28 nm Bulk-CMOS process. The phase accuracy is better than ±3° up to 2.5 GHz and better than ±5° among the entire operating frequency region achieving a phase noise performance of -163.2 dBc/Hz at 100 MHz offset at 2 GHz with a power consumption of only 4.4 mW with a 1.1V supply.