Phase Interpolator with Improved Linearity

Abstract

An analog phase interpolator with improved step linearity is presented in this paper. The linearity is improved by setting the time constant of the output nodes in suitable value and by employing a fine trimming technique. The performance and the improved linearity have been verified with post-layout simulations using a well-established CMOS 65 nm technology and transistors with standard threshold voltages. The clock frequency is at 2.5 GHz and the core voltage supply at 1.2 V. Its low phase noise makes the circuit suitable for high-speed systems where low jitter performance is required. © 2015, Springer Science+Business Media New York.