Abstract:

Time-to-Digital Converter (TDC) is an important component of the all-digital phaselocked loop (ADPLL), which plays the role of phasefrequency detector.This paper focuses on the enhancement of alldigital TDC resolution.We present the basic structures of three categories of alldigital TDC, which are counter based TDC,gate-delay-line based TDC and subgate delay TDC.We also demonstrate their respective advantages from the aspects of resolution,dynamic range,nonlinearity and etc.Finally,we summarize and make projection on future research priorities.

Key words: TDC；resolution；dynamic range；ADPLL