Fully integrated CMOS power amplifier design using the distributed active-transformer architecture

A novel on-chip impedance matching and power-combining method, the distributed active transformer is presented. It combines several low-voltage push-pull amplifiers efficiently with their outputs in series to produce a larger output power while maintaining a 50-Ω match. It also uses virtual ac grounds and magnetic couplings extensively to eliminate the need for any off-chip component, such as tuned bonding wires or external inductors. Furthermore, it desensitizes the operation of the amplifier to the inductance of bonding wires making the design more reproducible. To demonstrate the feasibility of this concept, a 2.4-GHz 2-W 2-V truly fully integrated power amplifier with 50-Ω input and output matching has been fabricated using 0.35-μm CMOS transistors. It achieves a power added efficiency (PAE) of 41 % at this power level. It can also produce 450 mW using a 1-V supply. Harmonic suppression is 64 dBc or better. This new topology makes possible a truly fully integrated watt-level gigahertz range low-voltage CMOS power amplifier for the first time

Novel active function blocks and their applications in frequency filters and quadrature oscillators

Kmitočtové filtry a sinusoidní oscilátory jsou lineární elektronické obvody, které jsou používány v široké oblasti elektroniky a jsou základními stavebními bloky v analogovém zpracování signálu. V poslední dekádě pro tento účel bylo prezentováno velké množství stavebních funkčních bloků. V letech 2000 a 2006 na Ústavu telekomunikací, VUT v Brně byly definovány univerzální proudový konvejor (UCC) a univerzální napět'ový konvejor (UVC) a vyrobeny ve spolupráci s firmou AMI Semiconductor Czech, Ltd. Ovšem, stále existuje požadavek na vývoj nových aktivních prvků, které nabízejí nové výhody. Hlavní přínos práce proto spočívá v definici dalších původních aktivních stavebních bloků jako jsou differential-input buffered and transconductance amplifier (DBTA), current follower transconductance amplifier (CFTA), z-copy current-controlled current inverting transconductance amplifier (ZC-CCCITA), generalized current follower differential input transconductance amplifier (GCFDITA), voltage gain-controlled modified current-feedback operational amplifier (VGC-MCFOA), a minus-type current-controlled third-generation voltage conveyor (CC-VCIII-). Pomocí navržených aktivních stavebních bloků byly prezentovány původní zapojení fázovacích článků prvního řádu, univerzální filtry druhého řádu, ekvivalenty obvodu typu KHN, inverzní filtry, aktivní simulátory uzemněného induktoru a kvadraturní sinusoidní oscilátory pracující v proudovém, napět'ovém a smíšeném módu. Chování navržených obvodů byla ověřena simulací v prostředí SPICE a ve vybraných případech experimentálním měřením.Frequency filters and sinusoidal oscillators are linear electric circuits that are used in wide area of electronics and also are the basic building blocks in analogue signal processing. In the last decade, huge number of active building blocks (ABBs) were presented for this purpose. In 2000 and 2006, the universal current conveyor (UCC) and the universal voltage conveyor (UVC), respectively, were designed at the Department of Telecommunication, BUT, Brno, and produced in cooperation with AMI Semiconductor Czech, Ltd. There is still the need to develop new active elements that offer new advantages. The main contribution of this thesis is, therefore, the definition of other novel ABBs such as the differential-input buffered and transconductance amplifier (DBTA), the current follower transconductance amplifier (CFTA), the z-copy current-controlled current inverting transconductance amplifier (ZC-CCCITA), the generalized current follower differential input transconductance amplifier (GCFDITA), the voltage gain-controlled modified current-feedback operational amplifier (VGC-MCFOA), and the minus-type current-controlled third-generation voltage conveyor (CC-VCIII-). Using the proposed ABBs, novel structures of first-order all-pass filters, second-order universal filters, KHN-equivalent circuits, inverse filters, active grounded inductance simulators, and quadrature sinusoidal oscillators working in the current-, voltage-, or mixed-mode are presented. The behavior of the proposed circuits has been verified by SPICE simulations and in selected cases also by experimental measurements.

Derivation of Closed-Form Design Equations for Idealized Operation of Inverse Class-E Power Amplifiers at Any Duty Ratio

Complementary to the conventional class-E topology, inverse class-E operation has several advantages over the class-E counterpart, such as lower peak switch voltage and smaller circuit inductance, which are attractive to high power RF design and MMIC implementation. This paper derives the closed-form design equations that can be used to synthesize the idealized operation of inverse class-E power amplifiers at any switch duty ratio. Calculation of the key design parameters, such as the maximum switch voltage and circuit components values, is elaborated and compared with the case of conventional class-E operation. Further, the theoretical analysis is confirmed and verified by numerical simulations performed on a 500mW, 2.4GHz idealized inverse class-E power amplifier

Silicon-germanium BiCMOS device and circuit design for extreme environment applications

Silicon-germanium (SiGe) BiCMOS technology platforms have proven invaluable for implementing a wide variety of digital, RF, and mixed-signal applications in extreme environments such as space, where maintaining high levels of performance in the presence of low temperatures and background radiation is paramount. This work will focus on the investigation of the total-dose radiation tolerance of a third generation complementary SiGe:C BiCMOS technology platform. Tolerance will be quantified under proton and X-ray radiation sources for both the npn and pnp HBT, as well as for an operational amplifier built with these devices. Furthermore, a technique known as junction isolation radiation hardening will be proposed and tested with the goal of improving the SEE sensitivity of the npn in this platform by reducing the charge collected by the subcollector in the event of a direct ion strike. To the author's knowledge, this work presents the first design and measurement results for this form of RHBD.M.S.Committee Chair: Cressler, John; Committee Member: Papapolymerou, John; Committee Member: Ralph, Stephe

Communication Subsystems for Emerging Wireless Technologies

The paper describes a multi-disciplinary design of modern communication systems. The design starts with the analysis of a system in order to define requirements on its individual components. The design exploits proper models of communication channels to adapt the systems to expected transmission conditions. Input filtering of signals both in the frequency domain and in the spatial domain is ensured by a properly designed antenna. Further signal processing (amplification and further filtering) is done by electronics circuits. Finally, signal processing techniques are applied to yield information about current properties of frequency spectrum and to distribute the transmission over free subcarrier channels

Class E/F switching power amplifiers

The present invention discloses a new family of switching amplifier classes called class E/F amplifiers. These amplifiers are generally characterized by their use of the zero-voltage-switching (ZVS) phase correction technique to eliminate of the loss normally associated with the inherent capacitance of the switching device as utilized in class-E amplifiers, together with a load network for improved voltage and current wave-shaping by presenting class-F.sup.-1 impedances at selected overtones and class-E impedances at the remaining overtones. The present invention discloses a several topologies and specific circuit implementations for achieving such performance

A very low distortion high efficiency class-F power amplifier at 900 MHz.

This paper presents a novel class - F power amplifier for mobile applications in which with a proper harmonic tuning structure the need f or an extra fil tering section is eliminated . A class - F power a mplifier employing a GaN HEMT device has been designed, fabricated and measured at 900 MHz . The fabricated circuit achieves a n excel lent harmonic - suppression level and the t otal h armonic distortion is around 1.2% . It overcomes the narrow band performance of class - F power amplifier s, giving more than 70% efficiency over a 100 MHz bandwidth . Experimental results show that the amplifier is able to deliver 38.5 dBm output power while achieving the state - of - the - art PAE of 8 0.5 % with a peak drain eff iciency of 8 4 % , and a power gain of 13.6 dB for an input power of 25 dBm . A good agreement between measurement and simulation results is observed for the proposed structure.Peer ReviewedPostprint (published version

The Switched Mode Power Amplifiers

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High-Power Microwave/ Radio-Frequency Components, Circuits, and Subsystems for Next-Generation Wireless Radio Front-Ends

As the wireless communication systems evolve toward the future generation, intelligence will be the main signature/trend, well known as the concepts of cognitive and software-defined radios which offer ultimate data transmission speed, spectrum access, and user capacity. During this evolution, the human society may experience another round of `information revolution\u27. However, one of the major bottlenecks of this promotion lies in hardware realization, since all the aforementioned intelligent systems are required to cover a broad frequency range to support multiple communication bands and dissimilar standards. As the essential part of the hardware, power amplifiers (PAs) capable of operating over a wide bandwidth have been identified as the key enabling technology. This dissertation focuses on novel methodologies for designing and realizing broadband high-power PAs, their integration with high-quality-factor (high-Q) tunable filters, and relevant investigations on the reliabilities of these tunable devices. It can be basically divided into three major parts: 1.Broadband High-Efficiency Power Amplifiers. Obtaining high PA efficiency over a wide bandwidth is very challenging, because of the difficulty of performing broadband multi-harmonic matching. However, high efficiency is the critical feature for high-performance PAs due to the ever-increasing demands for environmental friendliness, energy saving, and longer battery life. In this research, novel design methodologies of broad-band highly efficient PAs are proposed, including the first-ever mode-transferring PA theory, novel matching network topology, and wideband reconfigurable PA architecture. These techniques significantly advance the state-of-the-art in terms of bandwidth and efficiency. 2.Co-Design of PAs and High-Q Tunable Filters. When implementing the intelligent communication systems, the conventional approach based on independent RF design philosophy suffers from many inherent defects, since no global optimization is achieved leading to degraded overall performance. An attractive method to solve these difficulties is to co-design critical modules of the transceiver chain. This dissertation presents the first-ever co-design of PAs and tunable filters, in which the redundant inter-module matching is entirely eliminated, leading to minimized size & cost and maximized overall performance. The saved hardware resources can be further transferred to enhance system functionalities. Moreover, we also demonstrate that co-design of PAs and filters can lead to more functionalities/benefits for the wireless systems, e.g. efficient and linear amplification of dual-carrier (or multi-carrier) signals. 3.High-Power/Non-Linear Study on Tunable Devices. High-power limitation/power handling is an everlasting theme of tunable devices, as it determines the operational life and is the threshold for actual industrial applications. Under high-power operation, the high RF voltage can lead to failures like tuners\u27 mechanical deflections and gas discharge in the small air spacing of the cavity. These two mechanisms are studied independently with their instantaneous and long-term effects on the device performance. In addition, an anti-biased topology of electrostatic RF MEMS varactors and tunable filters is proposed and experimentally validated for reducing the non-linear effect induced by bias-noise. These investigations will enlighten the designers on how to avoid and/or minimize the non-ideal effects, eventually leading to longer life cycle and performance sustainability of the tunable devices