Digital Approaches on Frequency Tuning for Magnetoelectric Sensors

Magnetoelectric sensor concepts typically require magnetic or electrical excitation signals with a specific frequency and amplitude for operation. These required signals present a challenge in terms of the necessary frequency accuracy to enable ME sensors operation at their particular resonance frequency. This work compares two digital designs for generating the electrical signal that drives the composite ME sensors. The first one includes a Variable-Content Look-Up-Table Single-Side-Band modulation, and the second one is a Direct-Digital-Synthesizer implementation. The Direct-Digital-Synthesizer proves to be the best in terms of its obtained Signal-to-Noise-Ratio equal to 38.09 dB, Spurious-Free-Dynamic-Range equal to 39.12 dB, and Total-Harmonic-Distortion plus Noise equivalent to 1.25% after the filtering stage. Additionally, it can cover the frequency range from 384.62 kHz to 781.23 kHz with an achievable resolution of ( $11.95\pm 1.10$ ) Hz. The DDS architecture is synthesized in a 180 nm integrated circuit technology on Gate-Level-Netlist hierarchy using Cadence Genus Synthesis Solution Tool. The simulated power consumption is $46.46\ \mu\mathrm{W}$ , and the area consumption is $91 \mu\mathrm{m}\times91\ \mu\mathrm{m}$ .