A fully reconfigurable low-power floating-gate transistor-capacitor filter

This paper presents a fully reconfigurable low-power filter that is composed of a cascade of floating-gate transistor-capacitor (FGT-C) biquadratic sections suitable for biomedical applications. The proposed FGT-C filter provides both the lowpass and bandpass outputs to the following stage with all filter parameters reconfigurable, including the gains, natural frequency, quality factor, DC levels for input and outputs. The filter topology exhibits good modularity so that the biquadratic sections can be cascaded and scaled up to implement high-order frequency responses easily with efficient area and power consumption. A prototype chip has been fabricated in a 0.35μm 2P4M CMOS process and each FGT-C biquadratic filter occupies an area of 0.0313mm2. From measurement results, the filter consumes 118.4nW of power with a dynamic range of 45.5dB while operating at 1.8V power supply with a 10kHz bandwidth.