Electrical impedance spectroscopy (EIS) is a powerful technology for accurate disease detection at the pointof-care (POC) from biosensors. Nevertheless, EIS usually involves lock-in amplifiers and mixers to detect both the magnitude and phase of the complex impedances. This paper presents a highly digital impedance measurement system-onchip, which can convert the magnitude and phase of impedance to 10-bits digital codes integrated with a filter-based wide-range programmable sinusoidal wave synthesizer (SWS). The proposed SWS utilizes switched-capacitor circuits such that the corner frequency can be adjusted by changing its switching frequency. The proposed EIS system was fabricated using a 180nm process with an active area of only 0.35 mm 2 . The SWS generates output frequency in the range of 579 µHz-48.9 kHz with measured total harmonic distortion of 0.152% at 100 Hz and 0.116% at 10 kHz. The DNL of the proposed magnitude converter is within −0.34/+0.3 LSB and the INL is around −0.75/+2 LSB. To validate the function of the proposed EIS measurement system, it is utilized to detect the tumor necrosis factor α in biological samples.

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