Ring and coupled ring oscillator in subthreshold region

In this paper, the implementation of oscillators in the subthreshold region is proposed. The ring and coupled ring oscillators are implemented. The technique of swapped body biasing technique has been introduced for coupled ring oscillators to enhance their performance. The functionality of the oscillators in subthreshold region is verified through simulations using 180 nm TSMC CMOS technology parameters. A comparison in performance of the oscillators is carried out. It is found that coupled ring oscillator based on the swapped body biasing shows the best performance with the frequency of oscillation, power and propagation delay as 19.79 MHz, 973 nW and 12.84 ns respectively.