High-Performance Multi-Stage CMOS OTA Design Using Differential Block As Compensation Network

This work presents an effective and straightforward frequency compensation scheme in CMOS three-stage amplifiers. Using a differential block in the compensation network, the proposed circuit shows independent and large first dominant pole regarding the DC gain path. The presented three-stage architecture is frequency-compensated just by a single Miller capacitor. Mathematical analysis is presented along with ample simulations that are performed using TSMC 0.18-[Formula: see text]m CMOS technology. According to the results, the proposed circuit shows DC gain equal to 118[Formula: see text]dB, GBW equal to 466[Formula: see text]MHz, PM equal to 74.3∘ and 1.2[Formula: see text]mW as power consumption, respectively. The high values of DC gain and GBW make the proposed amplifier appropriate for more speedy operations such as high-speed modulators and data converters.

A High Bandwidth-Power Efficiency, Low THD2,3 Driver Amplifier with Dual-Loop Active Frequency Compensation for High-Speed Applications

This paper presents a driver amplifier with high bandwidth-power efficiency, high capacitor-driving capacity, and low total harmonic distortion (THD). One complementary differential pair composed of self-cascode transistors is incorporated to obtain a full input voltage swing. Flipped voltage follower (FVF) buffers are applied as second stage to drive the last class-AB output stage. Moreover, a dual-loop active-feedback frequency compensation (DLAFC) is presented, which can stabilize the proposed multistage amplifier and keep the dominant pole on high frequency to obtain high-frequency total harmonic distortion (THD) suppression. To achieve a low-frequency phase margin protection (PMP), one left half-plane (LHP) zero is introduced to compensate for the nondominant pole caused by the load capacitor. Meanwhile, two high-frequency LHP zeros are injected to achieve high-frequency phase margin boosting (PMB) and reduce the amplifier’s settling time and integration area. This proposed amplifier is implemented in a standard DBH 0.18 μm 5 V CMOS process, and it achieves over 115-dB DC gain, 150–300 MHz GBW under 0–100 p load capacitors, ultra-high THD2,3 suppression ranges from 100 kHz to 10 MHz under 1–2 V output swing, and over 250 V/μs average slew rate, by only dissipating 12.5 mW at 5 V power supply.

A High Gain, High BW OP AMP with Frequency Compensation Techniques at 65 nm Technology

OP-AMPs finds applications in different domains of electronics engineering including communications. There has been several OP-AMP configurations realized in the last decades for different target applications. But with the evolution of communication standards, to meet the demand for high data rate over the years, requirement for a high frequency and high BW OP-AMP is gaining attention. This makes the design challenge much higher. This paper presents a two-stage CMOS amplifier which uses frequency compensation method to facilitate higher BW. Different parameters like Gain, Gain band width product (GBWP), Phase Margin and Total Power dissipation are considered in this design. A step-by-step procedure for an efficient amplifier design is followed using frequency compensation. We have achieved a gain-bandwidth product (GBWP) of 110 MHz that is capable of driving large capacitive loads. It also achieves 77.7 dB gain with a phase margin of 60o.

Power-Law Compensator Design for Plants with Uncertainties: Experimental Verification

A power-law compensator scheme for achieving robust frequency compensation in control systems including plants with an uncertain pole, is introduced in this work. This is achieved through an appropriate selection of the compensator parameters, which guarantee that the Nyquist diagram of the open-loop system compensator-plant crosses a fixed point independent of the plant pole variations. The implementation of the fractional-order compensator is performed through the utilization of a curve-fitting-based technique and the derived rational integer-order transfer function is realized on a Field-Programmable Analog Array device. The experimental results confirm that the the phase margin is well preserved, even for ±40% variation in the pole location of the plant.