A rail-to-rail DC-enhanced adaptive biased fully differential OTA

In this paper a novel rail-to-rail fully differential operational transconductance amplifier (OTA) working at lowsupply voltages (1.5V) with reduced consumption and showing high DC gain is presented. An adaptive biasing circuit allows to obtain low stand-by power dissipation (lower than 0.19 mW in the rail-to-rail version), while the high DC gain (over 80 dB) is ensured by a positive feedback. The circuit, designed in a standard CMOS integrated technology (AMS 0.35 μm), has a 40 V/μs slew-rate for a capacitive load of 15 pF. The calculated values of two quality factors, named FOM
S/L
in the literature, show the validity of the proposed OTA.