A Wideband Low-Power LC-DCO-Based Complex Dielectric Spectroscopy System in 0.18- $\mu \text{m}$ CMOS

A low-power integrated LC-oscillator-based broadband dielectric spectroscopy (BDS) system is presented. The real relative permittivity εr' is measured as a shift in the oscillator frequency using an on-chip frequency-to-digital converter. The imaginary relative permittivity εr" increases the losses of the oscillator tank which mandates a higher dc biasing current to preserve the same oscillation a...