A 2.5-GHz four-phase clock generator with scalable no-feedback-loop architecture

An accurate yet simple multiphase clock generator has been developed by usi ng a delay compensation technique based on phase interpolation that supplie s a multiphase clock signal without increasing local circuit area. This gen erator is applied to the 2.5-GHz four-phase clock distribution of a 5-Gb/s x 8-channel receiver fabricated with 0.13-mum CMOS technology. The four-pha se generator in the receiver consumes 30 mW and occupies only 0.009 mm(2). It requires only 1.5 clock cycles to produce accurate phase differences and can operate from 1.5 to 2.8 GHz, with a range of phase error within +/-5 d egrees.