Two new high-performance output stages are proposed. These output stages are basically designed by using a flipped voltage follower (FVF). The proposed low-power and low-voltage output stages have utilized the advantages of the FGMOS technology. They are characterized by low-power dissipation, reduced power supply requirement, and larger bandwidth. By using FGMOS-based FVF in place of conventional FVF, the linearity of the output stages has been highly improved. The small-signal analysis of FGMOS-based FVF is done to show the bandwidth enhancement of conventional FVF. The circuits are simulated to demonstrate the effectiveness using SPICE, in TSMC 0.25-micron CMOS device models. The simulation results show that the power supply requirement of the proposed output stages is highly reduced and bandwidths are extremely higher than the conventional circuits. 1. Introduction The challenge of designing of high performance low-voltage and low-power analog circuits is increasing due to the scaling down of CMOS technology and the increasing demand for portable electronic equipments [1]. The speed of conventional analog integrated circuits is degrading on reducing the supply voltage for a given technology. To fulfill these requirements, the researchers are focusing on the development of new integrated circuits that have low voltage supply requirement, without any degradation in the performance. One of the basic building blocks in analog signal processing circuits is voltage buffer, which is used to drive low-impedance loads (Figure 1(a)). The flipped voltage follower (FVF) [2] is a low-voltage operating buffer that can be used in different circuits in place of conventional voltage buffer very efficiently. A FVF circuit is shown in Figure 1(b). Figure 1: (a) Voltage follower and (b) flipped voltage follower. A FVF cell has found increasing applications in areas where a voltage buffer is required. These applications include operational amplifier, current mirror, output stages, and arithmetic circuits and act as a basic building block in various analog circuits [2–7]. The advantages of FVF include low supply voltage requirement, almost unity gain, and high current-sinking capabilities [2]. Ramirez-Angulo et al. [3] have introduced an FVF which is based on FGMOS level shifter stage, shown in Figure 2. Due to its high swing and low voltage operation, the FGMOS-based FVF can be preferred over conventional FVF in many high-swing, low-power, and wideband analog integrated circuits. Figure 2: FVF using floating gate level shifter [ 3]. Applications for communication
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