A Novel Structure of Wide-Swing CMOS Voltage Buffer

This paper presents a novel structure of wide- swing CMOS voltage buffer, which is based on the flipped voltage follower. When compared with the previously established buffer based on the same principle, the proposed circuit is less complex and consumes less power while attaining wide bandwidth and high slew-rate. Simulated results of the proposed buffer using a 0.35µm CMOS process are provided. I. INTRODUCTION Analog voltage buffers or voltage followers can be found in various analog applications such as current conveyors (1), current feedback amplifiers (2), output stages of power amplifiers and line drivers (3), and analog filter realizations (4). In order to drive large capacitive loads with high speed and attain high signal-to-noise ratios, analog buffers must provide an output current and voltage swing range which is as high as possible. To meet these requirements, a fast, unity-gain class-AB amplifier circuit with rail-to-rail signal capability is required. Combining the class-AB operation and rail-to-rail signal swing usually requires a complicated biasing circuit to extend the common-mode input range of the buffer (5). Unfortunately, this increases the buffer complexity and power