There are three basic input structures for single-supply voltage-feedback amplifiers. This video provides an overview of various input structures for CMOS voltage-feedback amplifiers, and discusses how these structures affect the amplifier's ability to support rail-to-rail operation. For further information, please visit www.microchip.com/linear, or the Op-amp Self Paced Training.
Basic Amplifier Input Structure
Amp'titudes Episode 3 - Rail-to-Rail Input Stage