Phase-Locked Loop-Based Nanoresonator Integrated Circuit for Motional Resistance Sensing with Automatic Gain Control

This paper presents a phase-locked loop (PLL)-based resonator driving integrated circuit (IC) for motional resistance sensing with automatic gain control(AGC). The PLL makes the driving frequency to be locked at the nanoresonator resonant frequency. The automatic parasitic capacitance cancellation loop included in the IC automatically compensates the parasitic capacitance of the nanoresonator. The AGC loop keeps the oscillation at the suitable amplitude, and the motional resistance can be detected by the AGC digital output.