Low-voltage power-efficient adaptive biasing for CMOS amplifiers and buffers

Novel adaptive biasing techniques, suited for low-voltage operation, are presented. They provide small and accurately controlled quiescent currents, which are automatically boosted when an input signal is applied. Measurement results of an OTA using these techniques and fabricated in a 0.5 (mu)m CMOS technology show a slew rate of more than 40 V/(mu)s for an 80 pF load capacitance and a static power consumption of only 140 (mu)W.