Cell-Based Process Resilient Multiphase Clock Generation

Abstract

Multiphase clock generation (MPCG) is a problem that aims to generate a sequence of clock signals with the same frequency and uniformly shifted phases. In this brief, we present a cell-based MPCG design with two technical merits. We use a process calibration scheme that makes the per-phase delay (defined as the timing difference between two consecutive phases of clock signals) highly accurate. We further exploit a so-called cyclic property to make the achievable per-phase delay much smaller than a buffer delay. A design with 16-phase clock signal (with the per-phase delay of only 100 ps) is used to demonstrate its effectiveness.