A Low‐Voltage Hybrid CMOS‐Memristor‐Based Wideband Class‐AB Amplifier for Portable Electronic Device Applications

Abstract

This paper presents a low-voltage high-gain wideband three-stage true-class-AB amplifier. This is realized in the 0.18 μm CMOS process. The three-stage class-AB amplifier is proposed based on a compensation topology called nested Miller compensation along with a memristor to get pole-zero cancellation, which arises beyond the unity gain frequency. The circuit is implemented without the need for extra components as transistors, resistors, and capacitors, thus saving the complexity of the circuit and power consumption. The circuit is designed to operate with a supply voltage of ±1 V along with a bias current of 175 μA. The simulation results indicate that this proposed amplifier is capable of driving wide range of resistive and capacitive loads, furthermore capable of maintaining a phase margin of more than 60°. The total compensation capacitor is 2 pF, which is much lesser as compared to pseudo- and true-class AB amplifier, which implies a reduction in area. Simulation results show that the unity gain frequency of the proposed class-AB amplifier is 136.7 MHz, which is much higher as compared to the counterpart topologies. The major advantage associated with this work is a very high bandwidth attained without affecting the gain of the amplifier.

Overview of Memristor-Based Design for Analog Applications

“…Its unity gain frequency is 136.7 MHz, offering a high bandwidth without affecting the amplifier gain. Also, the simulation results show that the proposed amplifier is designed to handle a variety of load configurations to ensure optimal performance in different scenarios (200 pF//1 MΩ, 100 pF//10 KΩ, and 25 pF//1 KΩ), as depicted in Figure 6b [51]. The amplifier's gain ranges from 70.5 dB to 92 dB.…”

“…The growing demand for multi-band and multi-standard wireless devices requires flexible designs that can support multiple frequency bands and communication protocols in a single device, such as Wi-Fi, Bluetooth, and cellular. In [51], a low-voltage high-gain wideband three-stage true-class AB amplifier is presented. The schematic of the proposed amplifier is depicted in Figure 6a [51] and designed using a 0.18 µm CMOS process.…”

“…The schematic of the proposed amplifier is depicted in Figure 6a [51] and designed using a 0.18 µm CMOS process. As shown in Figure 6b [51], the amplifier achieves a tunable high gain and operates at a low supply voltage of 1.8 V, making it suitable for low-power applications. The memristorbased pole-zero cancellation improves the amplifier's performance in terms of linearity and distortion, while the nested Miller compensation technique helps to make it more stable and widen its bandwidth.…”

“…posed amplifier is designed to handle a variety of load configurations to ensure optimal performance in different scenarios (200 pF//1 MΩ, 100 pF//10 KΩ, and 25 pF//1 KΩ), as depicted in Figure 6b [51]. The amplifier's gain ranges from 70.5 dB to 92 dB.…”