A type III fast locking time PLL with transconductor-C structure

Abstract

This paper is presented a type III third-order charge pump PLL with transconductor-C (Gm-C) structure to achieve a PLL with fast locking time. To reach this goal, we have used Gm-C structure in the PLL loop. The advantage of this architecture is great loop gain while increases with the ratio Gm/C. As a result, the small signal settling time decreases and then, the locking time is reduced, significantly while the loop stability increases, as well. The performance of this architecture has been verified in an example. The simulation results show that there is almost 70% reduction in the settling time in comparison with the conventional second-order PLLs.