Controlled dither in 90 nm digital to time conversion based direct digital synthesizer for spur mitigation

Abstract

Dithering is used in many discrete to continuous value conversion functions to provide an effective fractional value. This paper reviews the application of dither to a digital-to-time converter (DTC) based digital synthesizer suitable for many common wireless communication systems. Measurements of a 90 nm CMOS implementation using a 5 bit DTC show extension to effective 8 bits.