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A low-power integrated LC-oscillator-based broadband dielectric spectroscopy (BDS) system is presented. The real relative permittivity ε _r ' is measured as a shift in the oscillator frequency using an on-chip frequency-to-digital converter. The imaginary relative permittivity ε _r " increases the losses of the oscillator tank which mandates a higher dc biasing current to preserve the same oscillation amplitude. An amplitude-locked loop is used to fix the amplitude and linearize the relation between the oscillator bias current and ε _r " . The proposed BDS system employs a sensing oscillator and a reference oscillator where correlated double sampling is used to mitigate the impact of flicker noise, temperature variations, and frequency drifts. A prototype is implemented in 0.18-μm CMOS process with a total chip area of 6.24 mm2 to operate in 1-6-GHz range using three dual bands LC oscillators. The total power consumption …