摘要
This work introduces an enhanced operational amplifier architecture in which four flipped voltage follower (FVF) cells act as adaptive tail current sources to improve the performance of a conventional current mirror (CM)-based design. The FVF cells dynamically boost the differential pair current beyond the nominal bias level during the slewing interval, enabling a significantly higher slew rate and reduced settling time. By employing both n-channel and p-channel input stages driving cascode loads, the proposed dual FVF-controlled tail sources improve efficiency for both small-and large-signal operations. Additionally, the use of supplementary input devices increases the overall transconductance, thereby achieving higher DC gain and extended gain-bandwidth product. The amplifier was implemented in TSMC 0.18-& micro;m CMOS technology and validated through measurements, demonstrating a DC gain of 73.3 dB, a unity-gain bandwidth of 98.4 MHz, and a slew rate of 102.7 V/& micro;s. The circuit operates from a 1.8-V supply, driving a 16-pF capacitive load, with a power consumption of 642 & micro;W.