A 60-dB Dynamic-Range CMOS Sixth-Order 2 . 4-Hz Low-Pass Filter for Medical Applications

The design and implementation of a fully integrated complementary metal–oxide–semiconductor (CMOS) sixth-order 2.4 Hz low-pass filter (LPF) for medical applications is presented. For the implementation of large-time constants both linearized operational transconductance amplifiers with reduced transconductance and impedance scalers schemes for grounded capacitors are employed. Experimental results for the filter have shown a dynamic range (DR) of 60 dB, while the harmonic distortion components are below 50 dB. The power consumption for the filter is below 10 W, the power supply is 1.5 V, and the active area is 1 mm. The filter was fabricated in a double poly double metal 0.8 m CMOS process.

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