A Wide-range 130-nm CMOS Statistic-based Frequency Ratio Calculator

This paper presents the first frequency ratio calculator (FRC), which calculates the frequency ratio of an input signal and a reference signal with an accuracy better than 0.01. The circuit implementation is based on the proposed statistic algorithm such that its performance is resistant to PVT variation. Developed in 130-nm CMOS technology, the input signal frequency range of the FRC is from 135 to 850 MHz. The ratio calculation time takes only two reference cycles. The FRC consumes 4.3 -15.9 mW from a 1.2V supply voltage for different input frequency.