Low power log-domain filter

This paper presents a second order low-pass filter employing the log-domain technique for low-voltage, low- power biomedical applications. The filter design is based on the dynamic translinear principle which exploits the non-linear current-voltage relationship of MOS transistors operating in sub- threshold region. The filter, designed in UMC 180 nm CMOS technology, operates with a 0.9 V supply voltage. It consumes a power of 45 nW for a cutoff frequency of 100 Hz. The dynamic range (DR) and figure of merit (FoM) of the filter are 55.6 dB and 61.3 fJ respectively. The DR and FoM of the filter is better than many designs found in the literature.