scholarly journals PENGUAT KELAS D DENGAN METODE SUMMING INTEGRATOR

eLEKTRIKA ◽  
2019 ◽  
Vol 11 (2) ◽  
pp. 12
Author(s):  
Budihardja Murtianta
Keyword(s):  
Main Part ◽  
Pulse Width Modulation ◽  
Audio Signal ◽  
Switching Frequency ◽  
Class Ab ◽  
Sawtooth Wave ◽  
Class D Amplifier ◽  
Class D ◽  
Class B ◽  
Digital Encoding

A class D amplifier is one in which the output transistors are operated as switches. When a transistor is off, the current through it is zero and when it is on, the voltage across it is small, ideally zero. Thus the power dissipation is very low, so it requires a smaller heat sink for the amplifier. Class D amplifier operation is based on analog principles and there is no digital encoding of the signal. Before the emergence of class D amplifiers, the standard classes were class A, class AB, class B, and class C. The classic method for generating signals driving a transistor MOSFET is to use a comparator. One input is driven by an incoming audio signal, and the other by a triangle wave or a sawtooth wave at the required switching frequency. The frequency of a triangular or sawtooth wave must be higher than the audio input. MOSFET transistors work in a complementary manner that operates as a switch. Triangle waves are usually generated by square waves fed to the integrator circuit. So the main part of processing audio signals into PWM (Pulse Width Modulation) is the integrator and comparator. In this paper, we will discuss the work of a class D amplifier system using the summing integrator method as its main part.

scholarly journals Analysis of the influence of load inductance on nonlinear distortions of a class D amplifier caused by «dead time»

2021 ◽  
pp. 32-37
Author(s):  
S. A. Naida ◽  
Y. O. Onykienko ◽  
O. I. Drozdenko ◽  
O. I. Smolenska ◽  
V. S. Baran ◽  
...  
Keyword(s):  
Computer Model ◽  
Dead Time ◽  
Audio Signal ◽  
Switching Frequency ◽  
Error Signal ◽  
Class D Amplifier ◽  
Input And Output ◽  
Class D ◽  
Nonlinear Distortions ◽  
Wide Range

Goal. Analysis of the effect of load inductance at the output of the class D amplifier for different values of the duration of «dead time» and assessment of the adequacy of existing mathematical models for calculating the THD at the output of the amplifier depending on the duration of «dead time». Methodology. The study of the effect of «dead time» on the THD was performed using a computer model of the half-bridge converter board EPC9035 from Efficient Power Conversion. This board contains GaN transistors EPC2022 eGaN®, the corresponding control driver and other necessary elements for operation. The use of GaN transistors has made it possible to investigate the operation in a wide range of frequent switching, both to control the motor and to amplify the audio signal. Results. It is established that the value of load inductance affects the level of nonlinear distortions caused by «dead time». At inductance values that provide a constant sign of the output current, a difference arises between the duration of the input and output pulses, which increases the THD. At inductance values, when the choke current changes sign during a pulse, there is no error between the duration of the input and output pulses. Changing the inductance changes the relationship between the error signal and the non-error signal. THD changes accordingly. At high conversion frequencies, the voltage spikes caused by the choke current through the built-in diodes during the dead time are partially compensated by overcharging the output capacitance of the transistors, which also reduces harmonic distortion. Originality. For the first time, the value of the THD at the outlets in the fallowness of the different indices of the inductance of the choke and the theoretical calculation of the value in the results of the computer model was obtained. Practical significance. The dependence of the THD values on the inductance of the choke for converters with a switching frequency range from 1 kHz to 400 kHz, which allows them to be used both to control the motor and to amplify the audio signal.

A dual-level dual-phase pulse-width modulation class-D amplifier with 0.001% THD, 112 dB SNR

2014 ◽  
Author(s):  
Shang-Hsien Yang ◽  
Yuan-Han Yang ◽  
Ke-Horng Chen ◽  
Chung-Chih Hung ◽  
Chin-Long Wey ◽  
...  
Keyword(s):  
Pulse Width ◽  
Pulse Width Modulation ◽  
Dual Phase ◽  
Class D Amplifier ◽  
Class D

scholarly journals An Energy-Efficient Integration of a Digital Modulator and a Class-D Amplifier

Electronics ◽  
2020 ◽  
Vol 9 (8) ◽  
pp. 1319
Author(s):  
Muhammad Yousuf Irfan Zia ◽  
Raúl Tierno ◽  
Miguel-Ángel Luque-Nieto ◽  
Pablo Otero
Keyword(s):  
Power Amplifier ◽  
Energy Efficient ◽  
Pulse Width Modulation ◽  
Cost Effective ◽  
Theoretical Concept ◽  
Integrated System ◽  
Class D Amplifier ◽  
Class D ◽  
Shift Keying ◽  
Efficient Integration

Energy consumption is always a key feature in devices powered by electric accumulators. The power amplifier is the most energy-demanding module in mobile devices, portable appliances, static transceivers, and even nodes used in underwater acoustic networks. These devices incorporate a modulator, typically a pulse-width modulation (PWM) and a class-D power amplifier, for higher efficiency. We propose a technique to integrate the modulator of a transmitter and PW-modulator of a class-D amplifier to improve the overall efficiency of the system. This integrated set operates as an up-converter, phase modulator (PM), and binary phase-shift keying (BPSK) modulator under certain conditions. The theoretical concept is verified using Matlab and a model is designed and simulated in Simulink. For validation purposes, an electronic circuit is built and tested using Multisim. The results obtained by simulations and circuit implementation show that the proposed integrated system is an energy-efficient and cost-effective solution compared to conventional techniques.

Robust digital control of a class-D amplifier with low switching frequency for vibration generator

2017 ◽  
Author(s):  
Kazuki Hanabusa ◽  
Kohji Higuchi ◽  
Tatsuyoshi Kajikawa ◽  
Suttichai Premrudeepreechacharn ◽  
Kamon Jirasereeamornkul
Keyword(s):  
Digital Control ◽  
Switching Frequency ◽  
Class D Amplifier ◽  
Class D

scholarly journals Realisierung eines verzerrungsarmen Open-Loop Klasse-D Audio-Verstärkers mit SB-ZePoC

2007 ◽  
Vol 5 ◽  
pp. 225-230
Author(s):  
O. Schnick ◽  
W. Mathis
Keyword(s):  
Pulse Width Modulation ◽  
High Efficiency ◽  
Open Loop ◽  
Modulation Scheme ◽  
Audio Signals ◽  
Class D Amplifier ◽  
Class D ◽  
Zero Position ◽  
Digitally Controlled ◽  
Position Coding

Abstract. In den letzten Jahren hat die Entwicklung von Klasse-D Verstärkern für Audio-Anwendungen ein vermehrtes Interesse auf sich gezogen. Eine Motivation hierfür liegt in der mit dieser Technik extrem hohen erzielbaren Effizienz von über 90%. Die Signale, die Klasse-D Verstärker steuern, sind binär. Immer mehr Audio-Signale werden entweder digital gespeichert (CD, DVD, MP3) oder digital übermittelt (Internet, DRM, DAB, DVB-T, DVB-S, GMS, UMTS), weshalb eine direkte Umsetzung dieser Daten in ein binäres Steuersignal ohne vorherige konventionelle D/A-Wandlung erstrebenswert erscheint. Die klassischen Pulsweitenmodulationsverfahren führen zu Aliasing-Komponenten im Audio-Basisband. Diese Verzerrungen können nur durch eine sehr hohe Schaltfrequenz auf ein akzeptables Maß reduziert werden. Durch das von der Forschungsgruppe um Prof. Mathis vorgestellte SB-ZePoC Verfahren (Zero Position Coding with Separated Baseband) wird diese Art der Signalverzerrung durch Generierung eines separierten Basisbands verhindert. Deshalb können auch niedrige Schaltfrequenzen gewählt werden. Dadurch werden nicht nur die Schaltverluste, sondern auch Timing-Verzerrungen verringert, die durch die nichtideale Schaltendstufe verursacht werden. Diese tragen einen großen Anteil zu den gesamten Verzerrungen eines Klasse-D Verstärkers bei. Mit dem SB-ZePoC Verfahren lassen sich verzerrungsarme Open-Loop Klasse-D Audio-Verstärker realisieren, die ohne aufwändige Gegenkopplungsschleifen auskommen. Class-D amplifiers are suiteble for amplification of audio signals. One argument is their high efficiency of 90% and more. Today most of the audio signals are stored or transmitted in digital form. A digitally controlled Class-D amplifier can be directly driven with coded (modulated) data. No separate D/A conversion is needed. Classical modulation schemes like Pulse-Width-Modulation (PWM) cause aliasing. So a very high switching rate is required to minimize the aliasing component within the signal band. This paper shows a first implementation of the new SB-ZePoC modulation scheme (Zero Position Coding with Separated Baseband), which allows the generation of a binary signal with separated baseband. Therefore Class-D amplifiers using SB-ZePoC can be run with very low switching rates. Some benefits and problems in the design process because of low switching rates will be discussed. Measurements of a realtime implementation will be presented.

scholarly journals Design of Class D Audio Power Amplifier Suitable to Hearing Aid Devices

2020 ◽  
Vol 9 (3) ◽  
pp. 143-152
Keyword(s):  
Power Amplifier ◽  
Power Efficiency ◽  
Hearing Aid ◽  
Power Level ◽  
Class Ab ◽  
Class A ◽  
Class D Amplifier ◽  
Audio Amplifier ◽  
Class D ◽  
Audio System

An amplifier is an electronic circuit that improves the strength of the signal. Using an amplifier in an audio system is essential to improve the strength of the signal. Based on different applications and specifications different types of amplifiers are used. Generally in an audio system, the input signal is amplified to a minimum required power level and then the speaker is driven by it. Conventionally, the output stage of an audio amplifier uses Class-A or Class-AB operating in a linear transfer region. The power efficiency of the Class-D amplifier has a better output efficiency compared to Class-A and Class-AB amplifiers, and its distortion is lower than that of the Class-C amplifier. This is based on a known fact that the Class D amplifier has a switching action in which the transistors are either completely on or off. As a result, the amplification is achieved with no power dissipation. Hence, the size of the amplifier can be highly reduced and a smaller heat sink is required. This paper focuses on designing a Class-D power amplifier which is suitable for hearing aid devices to deliver 500mW output power and for the THD to be less than 3%. The circuit implementation is done using UMC high voltage 0.18μm technology. This amplifier consists of three stages such as the modulation stage, the driver stage, the bridge stage, and the demodulation stage. Unfortunately, the Class-D power amplifier has inherent non-linear distortion problems, which is more significant than conventional audio power amplifiers. In this thesis, negative feedback is employed to reduce THD. Without feedback, the THD is obtained as above 3%. By employing feedback, the THD was reduced by 1.96dB. This design result is discussed and through to realization; whereupon the effectiveness of each of the implementation is evaluated.

scholarly journals Perbandingan Efisiensi Daya Penguat Audio Kelas AB dengan Penguat Audio Kelas D untuk Keperluan Sound System Lapangan

2018 ◽  
Vol 10 (2) ◽  
pp. 54-58
Author(s):  
Muhamad Kharis ◽  
Dhidik Prastiyanto ◽  
Suryono Suryono
Keyword(s):  
Output Power ◽  
Power Efficiency ◽  
Input Power ◽  
Sound System ◽  
Class Ab ◽  
Audio Amplifiers ◽  
Class D Amplifier ◽  
Audio Amplifier ◽  
Class D ◽  
Field Sound

Class AB audio amplifiers are commonly used but the efficiency is 50%. While the efficiency of class D audio amplifiers is 90% but are rarely used. The purpose of this research is to know how much the power efficiency of field sound system between 1000 watts class AB amplifier and 900 watts class D amplifier. This study is a comparative study that compares different variables with the same sample. The results of power efficiency are obtained from the percentage comparison between the output power and the input power of each audio amplifier. The power efficiency of class D audio amplifiers with IRS D900 type larger than class AB audio amplifiers with Apex B500 type. The efficiency value of class D audio amplifiers at the highest output power reaches 87% while class AB audio amplifiers are only 73%.

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