Power-Combining Transformer Techniques for Fully-Integrated CMOS Power Amplifiers

Fully integrated CMOS power amplifiers (PAs) with parallel power-combining transformer are presented. For the high power CMOS PA design, two types of transformers, series-combining and parallel-combining, are fully analyzed and compared in detail to show the parasitic resistance and the turn ratio as the limiting factor of power combining. Based on the analysis, two kinds of parallel-combining transformers, a two-primary with a 1:2 turn ratio and a three-primary with a 1:2 turn ratio, are incorporated into the design of fully-integrated CMOS PAs in a standard 0.18-mum CMOS process. The PA with a two-primary transformer delivers 31.2 dBm of output power with 41% of power-added efficiency (PAE), and the PA with a three-primary transformer achieves 32 dBm of output power with 30% of PAE at 1.8 GHz with a 3.3-V power supply.     

A 2.4 GHz Fully Integrated Linear CMOS Power Amplifier With Discrete Power Control

A fully integrated 2.4 GHz CMOS power amplifier (PA) in a standard 0.18 $mu$m CMOS process is presented. Using a parallel-combining transformer (PCT) and gate bias adaptation, a discrete power control of the PA is achieved for enhancing the efficiency at power back-off. With a 3.3 V power supply, the PA has a peak drain efficiency of 33% at 31 dBm peak output power. By applying discrete power control, a reduction of 650 mA in current consumption can be achieved over the low output power range while satisfying the EVM requirements of WLAN 802.11g and WiMAX 802.16e signals.      

High‐Efficiency CMOS Power Amplifier Using Uneven Bias for Wireless LAN Application

This paper proposes a high‐efficiency power amplifier (PA) with uneven bias. The proposed amplifier consists of a driver amplifier, power stages of the main amplifier with class AB bias, and an auxiliary amplifier with class C bias. Unlike other CMOS PAs, the amplifier adopts a current‐mode transformer‐based combiner to reduce the output stage loss and size. As a result, the amplifier can improve the efficiency and reduce the quiescent current. The fully integrated CMOS PA is implemented using the commercial Taiwan Semiconductor Manufacturing Company 0.18‐μm RF‐CMOS process with a supply voltage of 3.3 V. The measured gain, P_1dB, and efficiency at P_1dB are 29 dB, 28.1 dBm, and 37.9%, respectively. When the PA is tested with 54 Mbps of an 802.11g WLAN orthogonal frequency division multiplexing signal, a 25‐dB error vector magnitude compliant output power of 22 dBm and a 21.5% efficiency can be obtained.     

A 0.25-/spl mu/m 20-dBm 2.4-GHz CMOS power amplifier with an integrated diode linearizer

A 2.4-GHz CMOS power amplifier (PA) with an output power 20 dBm using 0.25-/spl mu/m 1P5M standard CMOS process is presented. The PA uses an integrated diode connected NMOS transistor as a diode linearizer. It is believed that this is the first reported use of the diode linearization technique in CMOS PA design. It shows effective improvement in linearity from gain compression and ACPR measured results. Measurements are performed by using an FR-4 PCB test fixture. The fabricated power amplifier exhibits an output power of 20 dBm and a power-added efficiency as high as 28%. The obtained PA performances demonstrate the standard CMOS process potential for medium power RF amplification at 2.4 GHz wireless communication band.     

A 1.8-GHz CMOS Power Amplifier Using a Dual-Primary Transformer With Improved Efficiency in the Low Power Region

A 1.8-GHz CMOS power amplifier for a polar transmitter is implemented with a 0.18- RF CMOS process. The matching components, including the input and output transformers, were integrated. A dual-primary transformer is proposed in order to increase the efficiency in the low power region of the amplifier. The loss induced by the matching network for the low-output power region is minimized using the dual-primary transformer. The amplifier achieved a power-added efficiency of 40.7% at a maximum output power of 31.6 dBm. The dynamic range was 34 dB for a supply voltage that ranged from 0.5 to 3.3 V. The low power efficiency was 32% at the output power of 16 dBm.     

A 50 to 70 GHz Power Amplifier Using 90 nm CMOS Technology

A 50 to 70 GHz wideband power amplifier (PA) is developed in MS/RF 90 nm 1P9M CMOS process. This PA achieves a measured P_sat of 13.8 dBm, P_{1 dB} of 10.3 dBm, power added efficiency (PAE) of 12.6%, and linear power gain of 30 dB at 60 GHz under V_DD biased at 1.8 V. When V_DD is biased at 3 V, it exhibits P_sat of 18 dBm, P_{1 dB} of 12 dBm, PAE of 15%, and linear gain of 32.4 dB at 60 GHz. The MMIC PA also has a wide 3 dB bandwidth from 50 to 70 GHz, with a chip size of 0.66 times 0.5 mm². To the author's knowledge, this PA demonstrates the highest output power, with the highest gain among the reported CMOS PAs in V-band.     

Fully Integrated CMOS Power Amplifier With Efficiency Enhancement at Power Back-Off

This paper presents a new approach for power amplifier design using deep submicron CMOS technologies. A transformer based voltage combiner is proposed to combine power generated from several low-voltage CMOS amplifiers. Unlike other voltage combining transformers, the architecture presented in this paper provides greater flexibility to access and control the individual amplifiers in a voltage combined amplifier. In this work, this voltage combining transformer has been utilized to control output power and improve average efficiency at power back-off. This technique does not degrade instantaneous efficiency at peak power and maintains voltage gain with power back-off. A 1.2 V, 2.4 GHz fully integrated CMOS power amplifier prototype was implemented with thin-oxide transistors in a 0.13 mum RF-CMOS process to demonstrate the concept. Neither off-chip components nor bondwires are used for output matching. The power amplifier transmits 24 dBm power with 25% drain efficiency at 1 dB compression point. When driven into saturation, it transmits 27 dBm peak power with 32% drain efficiency. At power back-off, efficiency is greatly improved in the prototype which employs average efficiency enhancement circuitry.     

Tournament-Shaped Magnetically Coupled Power-Combiner Architecture for RF CMOS Power Amplifier

A tournament-shaped magnetically coupled power-combiner architecture for a fully integrated RF CMOS power amplifier is proposed. Various 1 : 1 transmission line transformers are used to design the power combiner. To demonstrate the new architecture, a 1.81-GHz CMOS power amplifier using the tournament-shaped power combiner was implemented with a 0.18-mum RF CMOS process. All of the matching components, including the input and output transformer, were fully integrated. The amplifier achieved a drain efficiency of 38% at the maximum output power of 31.7 dBm.     

应用于无线传感器网络的功率放大器的设计

给出一种基于TSMC 0.18 μm RF CMOS工艺,应用于无线传感器网络的2.4 GHz 功率放大器的设计.该功率放大 器工作频率范围为2.4 GHz～2.4835 GHz,采用全差分AB类共源共栅电路结构,使用功率控制技术以节省功耗,当输入信号 功率-12.5 dBm时,输出功率在-10.4 dBm至5.69 ...     

CMOS high linearity PA driver with an on-chip transformer for W-CDMA application

A fully integrated high linearity differential power amplifier driver with an on-chip transformer in a standard 0.13-μm CMOS process for W-CDMA application is presented.The transformer not only accomplishes output impedance matching,but also acts as a balun for converting differential signals to single-ended ones.Under a supply voltage of 3.3 V,the measured maximum power is larger than 17 dBm with a peak power efficiency of 21%.The output power at the 1-dB compression point and the power gain are 12.7 dBm and 13.2 dB,respectively. The die size is 0.91×1.12 mm~2.     

CMOS RF power amplifier with reconfigurable transformer

A CMOS RF power amplifier that can change the output transformer ratio is presented. The CMOS power amplifier is fully integrated in a 0.13 /spl mu/m process and has a power added efficiency (PAE) of 38% at 2.1 GHz and an output power of 30.7 dBm with 3.0 V supply voltage. The PAE at an output power of 16 dBm was increased by 40% by altering the transformer ratio.     

A Watt-Level Stacked-FET Linear Power Amplifier in Silicon-on-Insulator CMOS

A single-stage stacked field-effect transistor (FET) linear power amplifier (PA) is demonstrated using 0.28-$mu$ m 2.5-V standard I/O FETs in a 0.13- $mu$m silicon-on-insulator (SOI) CMOS technology. To overcome the low breakdown voltage limit of MOSFETs, a stacked-FET structure is employed, where four transistors are connected in series so that their output voltage swings are added in phase. With a 6.5-V supply, the measured PA achieves a small-signal gain of 14.6 dB, a saturated output power of 32.4 dBm, and a maximum power-added efficiency (PAE) of 47% at 1.9 GHz. Using a reverse-link IS-95 code division multiple access modulated signal, the PA shows an average output power of up to 28.7 dBm with a PAE of 41.2% while meeting the adjacent channel power ratio requirement. Using an uplink wideband code division multiple access modulated signal, the PA shows an average output power of up to 29.4 dBm with a PAE of 41.4% while meeting the adjacent channel leakage ratio requirement. The stacked-FET PA is designed to withstand up to 9 V of supply voltage before reaching its breakdown limit. This is the first reported stacked-FET linear PA in submicrometer SOI CMOS technology that delivers watt-level output power in the gigahertz frequency range with efficiency and linearity performance comparable to those of GaAs-based PAs.      

基于40 nm CMOS工艺的高效率功率放大器设计

针对硅基毫米波功率放大器存在的饱和输出功率较低、增益不足和效率不高的问题,基于TSMC 40nm CMOS工艺,设计了一款工作在28GHz的高效率和高增益连续F类功率放大器。提出的功率放大器由驱动级和功率级组成。针对功率级设计了一款基于变压器的谐波控制网络来实现功率合成和谐波控制,有效地提高了功率放大器的饱和输出功率和功率附加效率。采用PMOS管电容抵消功率级的栅源电容,进一步提高线性度和增益。电路后仿真结果表明,设计的功率放大器在饱和输出功率为20.5dBm处的峰值功率附加效率54%,1dB压缩点为19dBm,功率增益为27dB,在24GHz~32GHz频率处的功率附加效率大于40%。     

A Fully Integrated 3.3–3.8-GHz Power Amplifier With Autotransformer Balun

This paper demonstrates the usage of a differential autotransformer as an output balun for an integrated power amplifier (PA) operating at low-gigahertz frequencies. In comparison with a conventional transformer balun, an autotransformer balun offers lower power losses, thereby increasing the saturated output power and reducing the gain compression at the edge of target power range. A theoretical analysis of an integrated autotransformer is given, comparison with a magnetic transformer is performed. The concept was experimentally verified in a fully integrated PA for a 3.3-3.8-GHz WiMAX band fabricated in SiGe : C bipolar technology. The active part of the amplifier implements the derivative superposition method aimed at linearizing the power transfer characteristic. Measured PA delivers saturated output power above 29 dBm. The maximum achieved power-added efficiency exceeds 40% at 3.4 GHz. At 3.5 GHz, 1-dB gain compression occurs for P _out = 24.6 dBm.     

一种用于5G通信的高稳定双模功率放大器

采用国产40 nm CMOS工艺,设计了一种用于5G通信的28 GHz双模功率放大器。功率级采用大尺寸晶体管,获得了高饱和输出功率。采用无中心抽头变压器,消除了大尺寸晶体管带来的共模振荡问题。在共源共栅结构的共栅管栅端加入大电阻,提高了共源共栅结构的高频稳定性。采用共栅短接技术,解决了大电阻引起的差模增益恶化问题。在级间匹配网络中采用变容管调节,实现了双模式工作,分别获得了高功率增益和高带宽。电路后仿真结果表明,在高增益模式下,该双模功率放大器获得了20.8 dBm的饱和输出功率、24.5%的功率附加效率和28.1 dB的功率增益。在高带宽模式下,获得了20.6 dBm的饱和输出功率、22.6%的功率附加效率和12.2 GHz的3 dB带宽。     

A Fully Integrated UHF CMOS Power Amplifier for Spacecraft Applications

A power amplifier (PA) is designed for a surface-to-orbit proximity link microtransceiver on Mars exploration rovers, aerobots, and small networked landers and works in conjunction with a 0.2-dB loss transmit/receive switch to allow nearly the full 1 W to reach the antenna. The fully integrated UHF CMOS PA with more than 30-dBm output is reported for the first time. A differential pMOS structure with floating-bias cascode transistors and 1:3-turn ratio output transformer are chosen to overcome low breakdown voltage (V _bk) of CMOS and chip area consumption issues at UHF frequencies. The high-Q on-chip transformer on a sapphire substrate enables the differential PA to drive a single-ended antenna effectively at 400 MHz. The PA in a standard package delivers 30-dBm output with 27% power-added efficiency. No performance degradation was observed in continuous-wave operation and the design has been tested to 136% of its nominal 3.3-V supply without failure.     

A High Gain 77 GHz Power Amplifier Operating at 0.7 V Based on 90 nm CMOS Technology

A 77 GHz 90 nm CMOS power amplifier (PA) demonstrates a gain of 17.4 dB and a saturated output power of 5.8 dBm at a low supply voltage of 0.7 V. To take care of hot-carrier injection degradation, the supply voltage is reduced from a standard voltage of 1.0 V. The saturated output power is increased to 9.4 dBm with a linear gain of 20.6 dB at 1.0 V operation. The amplifier consists of three-stage common-source nMOSFETs with gate widths of 40, 80, and 160 $mu{rm m}$. To our best knowledge, the developed PA shows the highest gain ever achieved for W-band CMOS amplifier. The measured temperature characteristics suggest that a simple compensation technique is possible by gate bias control.      

2.4GHz CMOS高线性功率放大器

采用A类与B类并联的结构,设计了一种2.4GHz高线性功率放大器.输入信号较小时,A类放大器起主要作用;随着输入信号的增大,B类放大器起的作用越来越明显,来补偿A类的压缩,由此显著提高了放大器的线性度.电路主体为共栅管采用自偏置方法的共源共栅结构,提升了功放大信号工作时的可靠性.电路采用中芯国际0.13 μmCMOS工...     

A 1.83 GHz 28.5 dBm CMOS Power Up-Mixer

A power up-mixer is proposed in this letter. A merged CMOS linear power amplifier (PA) and mixer allows low current consumption and smaller chip size than a conventional integrated transmitter including a mixer and a CMOS linear PA. The chip is fabricated in a 0.18 $mu{rm m}$ CMOS process and in an integrated-passive-device. Measurements show a drain efficiency of 27% at 27.2 dBm of 1 dB compression point (P1dB) output power from 1.75 to 1.95 GHz. Power conversion gain is 26.4 dB and LO leakage is $-$43 dBc.      

一种用于便携式射频识别阅读器的CMOS功率放大器

针对一种特定的射频识别技术的通讯协议(ISO1800-6B),提出了一种应用于射频识别读写器中的发射机前端结构,以实现发射信号的OOK调制.采用0.18μm CMOS工艺实现的这种高效率、高度集成的无线发射机前端由射频信号调制器、E类功率放大器以及相应的逻辑控制单元组成,其中的功率放大器的小信号增益约为23dB,其1dB压缩点输出功率为17.6dBm,最大输出功率为19.0dBm,而最大功率增加效率为35.4%.整个发射机的输出信号满足相应协议的特定要求,可以实现不同调制深度(18%和100%)的射频信号输出.