A 0.5-V all-digital clock-deskew buffer with I/Q phase outputs

Abstract

This paper proposes a low supply voltage all-digital clock-deskew buffer with in-phase and quadrature phase (I/Q) outputs on an intra-chip. In some application-specific integrated chips or silicon intellectual properties might enter hibernation mode to conserve energy. The long locking time induces a large standby current, which results in greater power consumption. Furthermore, I/Q clock signals are widely adopted in the communication systems and double data rate memories. The proposed all-digital clock-deskew buffer can operate from 220 to 570 MHz at 0.5 V and the power consumption is 1.95 mW at 570 MHz. This buffer can also supply a quadrature phase output using a proposed two-step edge detector.