Vk1sv class e design class for beginners dimitrios tsifakis, vk1svsv1det. The class e amplifier with the capacitive coupling equivalent circuit is simulated in. Listed under the technical referenceamplifiershf amplifiers category that is about amateur linear amplifiers. Jan 27, 2015 this short video will provide an introduction to class f power amplifier design by first building a nonlinear device model and then using this model in a circuit simulation environment to generate.
The effect of the device output bondwire inductance on the optimum load network parameters is demonstrated. Jan 26, 2011 davis, rutledge,a lowcost class e amplifier with sinewave drive derstepanians, rutledge, 10mhz class e poweramplifiers melia, robert, oconner, class e power amplifier design. Classe cascode power amplifier analysis and design for long. Related to the hf tesla coil work, the class e rf power amplifier seeks to maximise the efficiency of the amplifier by optimising the times when the amplifier switching element turns on or off. Class t is a proprietary implementation of a class d amplifier it is not a class it its own right. The class e amplifier has a maximum theoretical efficiency of 100%. Class e amplifier was first presented by sokal in 1975. Filterless class d simplifies audio amplifier design ee times. Clever resonant load is constructed so that vt0 when the switch closes this avoids 12cv2f loss. In order to do this, the supply voltage can be increased. This is an aid for designing class e amplifiers, as described in nathan sokals paper titled class e rf power amplifiers, published in qex janfeb 2001. Brush up on the theory before designing a high power class.
Class e matching network typically presents a reactive load i. To download the project files referred to in this video visit. In order to calculate the values for the various components, the paper offers a set of equations that the amplifier designer can use. Class e amplifier driver vo voltage across switch is brought to zero when switch closes dvdt is also zero when switch closes. For many, it felt as if they truly started listening to. Perhaps there should be a section separate of the real classes of other or proprietary amplifiers which includes all other classes such as class i bca class td and class t oppose the merge w class t amplifier. Switchedmode parallelcircuit class e tuned power amplifiers. A 5v power supply is required for the driver and a dc input of 38v is required to acheive a 40w output. Class e amplifiers can be designed for narrowband operation or for fixedtuned operation over frequency bands as wide as 1. We would like to show you a description here but the site wont allow us. However, for a classe amplifier, as it will be explained later in detail, this causes a large stress on the dielectric of the switching. Threshold sa4e amplifier class a 100 wpc for sale us. In class e amplifiers there is a capacitor shunted across the.
A single rf amplifier is used for 80 and 160 meter operation, and there is. Classe cascode power amplifier analysis and design for. This used threshold sa4e amp is rated 100 watts per channel into 8 ohms and operates in pure class a mode. In this paper, an enhanced approach of a class e amplifier being insensitive to. Figure 1 shows a class ab amplifier configured in a bridgetiedload, btl, configuration. Fullyintegrated, programmable, polarmodulated class e. The classe amplifier has a maximum theoretical efficiency of 100%. The easy to use graphical interface will allow the user to increase the sound quality without causing any loss to the video files. Classe circuit calculator please input design specifications for your classe circuit. Class a amplifier circuit operation and applications. Audio amplifier software is need on operating systems like windows, linux, mac and also on mobiles which are ios and android base. The class g amplifier used in the multiple power supply rails of different voltages. With transistoramp you are able to create your individual transistor amplifier with a few mouse clicks. The efficiency of a power amplifier in the rf generator is improved by using class e amplifier.
The image of the conduction angle derives from amplifying a sinusoidal signal. The classe power amplifiers described here is based on a load network synthesized to have a. The tool transistoramp has a very easy to use user interface. This model shows a classe rf amplifier with circuit parameters chosen for an 80m wavelength. This short video will provide an introduction to class f power amplifier design by first building a nonlinear device model and then using this model in. Tayloe, class e amplifiers norcal qrp presentation class e design software from tonne software ive never used this, so use at your own risk wa0itp classe amplifier design spreadsheet ive never used this, so use at your own risk classe am forum. Tayloe, class e amplifiers norcal qrp presentation class e design software from tonne software ive never used this, so use at your own risk. The classe amplifier works in switched mode the transistor is driven hard enough to saturate in order to act as a switch with two discrete states, on and off. In this page, i will describe how to make a class e amplifier from scratch, that is how to design the circuitry required to produce a desired power at a desired frequency from a desired input voltage on a 50 ohm load or antenna. Making a software defined radio for the qrp enthusiast ae6ty.
Inverse class of operation by duality, any pa can be transformed into its dual where the role of currentvoltage are switched by imposing the complementary admittance condition for instance a class d voltage switching amplifier can be transformed into a current switching amp 44 chapter 3. These are tested, proven circuits that have been reproduced many times. In this paper, a new topology of the class e power amplifier pa is. In proceedings of the iasted international conference on wireless sensor networks, part of the sixth iasted international multiconference on wireless and optical communications vol. Power amplifier circuits output stages are classified as a, b, ab and c for analog designsand class d and e for switching designs. The ab amplifier is provided with an additional power supply unit operating with half the voltage.
Nocompromise audio performance with improved efficiency it is useful to expand class ab amplifier technology with class h switching, especially high output power amplifiers. Classe from tonne software, ltspice from linear technology. Classe amplification is easily differentiated from other classes of power amplification. Classes of amplifier operation rf amplifiers are classified a, ab, b or c according to the phaseangle number of degrees of current flow during each 360degree rf cycle over which plate or collectorcurrent flows. This is an aid for designing classe amplifiers, as described in nathan sokals paper titled classe rf power amplifiers, published in qex janfeb 2001.
Design specifications of the amplifier are to achieve an output rf power of. Classe amplifiers achieve high efficiency levels as the mosfets never have simultaneously high vds and ids. The main idea behind switchmode power amplifier technology is to operate the transistor in saturation, so that either voltage or current, depending on amplifier class. Typical classe power amplifier design for the clarification of the goals of this paper, a power amplifier circuit has been designed and simulated using a commercial microwave cad program. A programmable and selfadjusting class e amplifier for.
It is taken from sokals qex article see references. Classe, education technology, created and designed by teachers, classe adheres to the timeless principles of education while allowing the teacher to enhance the everyday classroom experience. Achieved output power of 27w at 92% efficiency successful class e power amplifier at. Advanced design system ads software for a different duty. Classe switchmode tuned power amplifier offers extremely high dc to ac conversion efficiency at high frequencies because of a significant reduction in switching losses 115. If harmonic outputs must be well below the carrier power, any amplifier other than class a or pushpull class ab cannot operate over a band. Operation is intuitive and encourages circuit exploration.
This transmitter uses a 5 mosfet pulse width modulator implemented using the class e pwm board set, and can be operated up to 1kw power input. For many, it felt as if they truly started listening to music after buying their first classe amplifier. The class e f amplifier is a highly efficient switching power amplifier, typically used at radio frequencies. Automatically switches between the supply rails as the input signal changes. The load network is used to shape the voltage and current waveforms. Audio management subsystem power amplifier, class d. In this page, i will describe how to make a classe amplifier from scratch, that is. Complete class e rf amplifiers are presented here, with all circuit and component values specified. If you are building a class e amplifier with a different configuration numbers of mosfets, frequency, etc. Class e amplifier 100% theoretical efficiency low number of components high reliability goal. The amp is a dual mono design with a pair of 800va toroidal transformers, 26 output transistors per channel and 190,000 total micro farads of filter capacitors. Classe amplifiers can be designed for narrowband operation or for fixedtuned operation over frequency bands as wide as 1.
In addition, these devices have been provided even more. They are also very well suited for amplification of frequency modulation or other modes where linear amplification is not a requirement. The simulation of the proposed circuit is performed using pspice software. Transistor amplifier circuit designer software electronic. You need to provide q, vcc, vo, p, f and l1 and the calculator will provide values for the rest. The main category is amateur linear amplifiers that is about hf amplifiers for ham radio use. By using a lowq resonant network in the drain circuit, we.
However, it does produce a digitallike output because the signals are generated by turning a switch fully on or off. The circuit operation is determined by the transistor when it is on and by the transient response of the load network when the transistor is off. It consists of a single transistor that is driven as a switch and a passive load network. Class e cascode power amplifier analysis and design for long term reliability by karan kutty b. This program simplifies the design of the singleended class e amplifier. This is a basic class e power amplifier designed using the procedures in rf power amplifiers for wireless communications crippsartech, chapter 6. We will now evaluate the software which runs on different operating platforms.
Jun 29, 2016 the classe amplifier works in switched mode the transistor is driven hard enough to saturate in order to act as a switch with two discrete states, on and off. Design of class e power amplifier with new structure and flat top. A single rf amplifier is used for 80 and 160 meter operation, and there is an individual rf ampflier for 40 meters. Class d amplifiers were developed as a way to increase the efficiency of audiopoweramplifier systems. The following schematic is a typical classe amplifier. Class a amplifier design produces a good linear amplifier, but most of the power produced by the amplifier goes wastage in the form of heat. The main concept used in this amplifier is to model the active switching device, such as a transistor or mosfet, as a linear combination of two parts. The driver stage must provide the output speci fied below. This link is listed in our web site directory since wednesday mar 14 2012, and till today 24 mosfet class e rf amplifier has been followed for a total of 1659 times. The passive load network is designed to minimize drain collector voltage and current waveforms overlapping, which minimize the output power dissipation. For example, as shown in figure 4, linear power amplifier in which the transistors is biased to an operating point and follows. Notice how the gate voltage waveform is rather bumpy and asymmetrical. Class e transmitters rf amplifier output circuit values.
Class e power amplifier design and optimization for the. Since the transistors in class a amplifier, are forward biased all the time, few current will flow through them even though there is no input signal and this is the main reason for its poor efficiency. This makes operation relatively insensitive to rise time of input. About 24 mosfet class e rf amplifier the resource is currently listed in in a single category.
Fullyintegrated, programmable, polarmodulated class e power amplifier. Each of the six design parameters can be specified using a freeform entry scheme. Design of highly efficient broadband classe power amplifier using. The classes and classification of amplifiers and its applications. The original and lauded dr2 classe amplifier was an unconventional product. As long as the power amplifier does not require a high output. In this page, i will describe how to make a classe amplifier from scratch, that is how to design the circuitry required to produce a desired power at a desired frequency from a desired input voltage on a 50 ohm load or antenna.
In class e amplifiers there is a capacitor shunted across the drain to source. The ncp2704 is a cost effective audio subsystem designed for portable applications such as cellular phones and portable media players. The rationale behind the selection of the final topology is discussed in detail. Transistoramp bjt transistor amplifier circuits designer software. A programmable and selfadjusting class e amplifier for efficient. At this range of frequency, class e amplifier has shown to exhibit efficiencies as high as 96% sokal, 1975.
There is none used here because the output capacitance of the device is slightly larger than the optimum value for that. Class e switchmode tuned power amplifier offers extremely high dc to ac conversion efficiency at high frequencies because of a significant reduction in switching losses 115. The operating power gain achieved with the parallelcircuit class e. The amp is a dual mono design with a pair of 800va toroidal transformers, 26 output transistors per channel and. Design of input matching networks for classe rf power. Class d amplifiers were developed as a way to increase the efficiency of audiopower amplifier systems.
To design a high efficient power amplifier capable of delivering high power for wireless communications andor wireless power transmission applications. Class e is a switching mode of operation, and exhibits extremely linear modulation characteristics, making these amplifiers well suited for high quality, amplitude modulation. The enhancement of class g amplifier is the basic of class ab amplifier. The applications of class e amplifiers were limited to the vhf band.
This model shows a class e rf amplifier with circuit parameters chosen for an 80m wavelength. For the design of transistor amplifiers there is a new software available. The class ef amplifier is a highly efficient switching power amplifier, typically used at radio frequencies. A class d amplifier or switching amplifier is an electronic amplifier in which the amplifying devices transistors, usually mosfets operate as electronic switches, and not as linear gain devices as in other amplifiers. The contact switching decreases the average power consumption hence, the power loss is produced by the wasted heat. Robust design methodology for classe amplifiers for microwave applications by srdjan aleksandar pajic. Then the input matching network will be designed using simulation software and a predesigned load network which is suggested to complete the class e amplifier. It has been designed to cover the power audio requirements in portable equipment, including a high fidelity class d speaker amplifier and a class g equivalent longplay true ground headphone amplifier.
Class e design program and it generated starting design values for the circuit. The efficiency of a power amplifier in the rf generator is improved by using classe amplifier. The official class e transmitter web site by wa1qix. The class e power amplifiers described here is based on a load network synthesized to have a. Some detailed notes on the derivation of the formulas for class e design. This type of behaviour seems to be usual and has been reported by davis and rutledge ibid. Voltage and current across transistor do not overlap, hence no power loss 8. Vk1sv classe design class for beginners dimitrios tsifakis, vk1svsv1det. It inspired the company name and inspired those music lovers with the good fortune to own one. You need to provide q, vcc, vo, p, f and l1 and the calculator will provide values for the. Tuning the drain capacitor shows a sharp tradeoff between efficiency and. The class d amplifier works by varying the duty cycle of a pulsewidthmodulated, pwm, signal. This section describes the various components used in class e rf amplifiers, and how the values of these components affect amplifier operation. Apt9903 4 class e design program and it generated starting design values for the circuit.
The classes are based on the proportion of each input cycle conduction angle during which an amplifying device passes current. Class e amplifiers achieve high efficiency levels as the mosfets never have simultaneously high vds and ids. Melia, robert, oconner, classe power amplifier design. Class e circuit calculator please input design specifications for your class e circuit.
The waveforms show the typical class e asymmetrical current pulse, and highly peaked voltage. The switching mode conditions and the bias network will be chosen too. You have the flexibility to choose the software which you need. Filterless class d simplifies audio amplifier design ee. University of central florida, 2008 a thesis submitted in partial fulfillment of the requirements.