A Pulse-Train Time Amplifier used for Time-based Phase detectors in ADPLLs

Abstract

This paper proposes a pulse-train time amplifier (PTTA) used in a Two-Step Time to Digital Converter (TDC) used as a phase detector in All-Digital Phase Locked Loops (ADPLLs). The proposed PTTA is an all-digital time amplifier based on the concept of time registers. Furthermore, the proposed PTTA has a lower amplification time compared to its counterpart. Therefore, the proposed PTTA allows reduction of the time resolution of the Two-Step TDC at the same conversion frequency or increase of the conversion frequency of the TwoStep TDC at the same time resolution.