High Slew-Rate and Very-Low Output Resistance Class-AB Flipped Voltage Follower Cell for Low-Voltage Low-Power Analog Circuits

A low output resistance and high slew rate class-AB flipped voltage follower (FVF) cell is presented in this paper. The proposed FVF cell consists of cascoding transistor which provides the extra gain to the feedback loop and leads to the low output resistance while the bulk-driven transistor acts as an adjustable current source to increase the current driving capability and slew rate. The proposed FVF cell offers numerous advantages such as low output resistance, high current driving capability, wide bandwidth, high symmetrical slew rate and occupies less chip area. The proposed circuit has been designed using Cadence virtuoso tool in 0.18 mu m CMOS technology and the post-layout simulation results are presented to validate its performance. To show the performance under extreme conditions, the analysis of the proposed circuit at various corners has also been presented.