Modeling and Simulation of Monolithic Single-Supply Power Operational Amplifiers

Ivailo Milanov Pandiev

doi:10.3390/en14154611

Abstract

In this paper a simple PSpice (Personal Simulation Program with Integrated Circuit Emphasis) macro-model was developed, and verified for monolithic power operational amplifiers operated with a single-supply voltage. The proposed macro-model is developed using simplification and build-up techniques for macro-modeling of operational amplifiers and simulates the basic static and dynamic characteristics, including input impedance, small-signal frequency responses at various voltage gains, output power versus supply voltage, slew-rate-limiting, voltage limiting, output offset voltage versus supply voltage ripples, and output resistance. Furthermore, the macro-model also takes into account the ground reference voltage in the amplifier at a single power supply voltage. The model is implemented as a hierarchical structure suitable for the PSpice circuit simulation platform. The sub-circuit is built using standard PSpice components and analog behavioral modeling blocks. The accuracy of the model is verified by extracting the model parameters for single-supply power operational amplifier TDA2005 from ST Microelectronics as example. The effectiveness of the model is validated by comparing the simulation results of the electrical parameters with the corresponding measured values obtained by experimental testing of sample circuits. The comparative analysis shows that the relative error of the modeled large-signal parameters is less than 15%. Moreover, an error of 15% is quite acceptable, considering the technological tolerances of the electrical parameters for this type of analog ICs.

Highlights

Despite the growing part of the digital devices in the modern electronic systems, there are still many applications that will always perform by analog circuits
According to the complexity of the amplitude-frequency characteristic of a concrete amplifier, the number of frequency-shaping stages can be increased, as well as the structure of the stage modeling the suppression of the pulsations in the supply voltage can be changed
The relative error, for some values of the input frequency, was greater than 20% (as the maximum value of the total harmonic distortion (THD) was below 1%), the results showed that the proposed macro-model can simulate the trend of change of nonlinear distortions in the process of preliminary studies of sample electronic circuits

Summary

Introduction

Despite the growing part of the digital devices in the modern electronic systems, there are still many applications that will always perform by analog circuits. In this paper, based on the simulation models, represented in [1,2,7], a simple electrical macro-model was developed, and verified for monolithic power amplifiers operated with a single-supply voltage. Some integrated circuits of the power amplifiers contain only an output stage, but often a preamplifier is included in the chip Their basic electrical circuit is similar to those with discrete components [11,12,13,14,15]. According to the complexity of the amplitude-frequency characteristic of a concrete amplifier, the number of frequency-shaping stages can be increased, as well as the structure of the stage modeling the suppression of the pulsations in the supply voltage can be changed

Thermal T3 protection

PSpice Implementation stage

Parameter Extraction

Findings

Conclusions