A 0.7V 24µA Hybrid OTA Driving 15 nF Capacitive Load With 1.46 MHz GBW

A cascade structure of six proposed signal-current enhancers is applied to a standard operational transconductance amplifier (OTA) to improve its gain-bandwidth (GBW) product, slew rate (SR), and voltage gain through significant enhancements of the small-signal and transient output currents from the proposed enhancers. The proposed hybrid OTA is implemented in a standard 0.13 μm CMOS technology, with an active chip area of 0.0027 mm. Working under a 0.7 V supply and as proven by the measurement results, the resultant OTA when driving an output capacitor of 15 nF attained ∼100 dB gain, a GBW of 1.46 MHz, and an SR of 0.47 V/μs, consuming only 24 μA of current and requiring no compensation capacitor.