Large swing CMOS power amplifier

A CMOS class AB power amplifier is presented in which supply-to-supply voltage swings across low-impedance loads are efficiently and readily handled. The amplifier consists of a high-gain input stage and a push-pull unity-gain amplifier output stage. The amplifier dissipates only 7 mW of DC power and delivers 36 mW of AC power to a 300-/spl Omega/ load, using standard power supplies of /spl plusmn/5.0 V. Lower impedance loads can be driven to higher power levels, providing the internal current limiting level is not exceeded.     

应用于10Gb/s光接收机的全差分CMOS跨阻前置电路设计

设计了一种的低成本、低功耗的10 Gb/s光接收机全差跨阻前置放大电路。该电路由跨阻放大器、限幅放大器和输出缓冲电路组成,其可将微弱的光电流信号转换为摆幅为400 mVpp的差分电压信号。该全差分前置放大电路采用0.18 m CMOS工艺进行设计,当光电二极管电容为250 fF时,该光接收机前置放大电路的跨阻增益为92 dB,-3 dB带宽为7.9 GHz,平均等效输入噪声电流谱密度约为23 pA/(0~8 GHz)。该电路采用电源电压为1.8 V时,跨阻放大器功耗为28 mW,限幅放大器功耗为80 mW,输出缓冲器功耗为40 mW,其芯片面积为800 m1 700 m。     

Multiple-quantum-well GaInAs/GaInAsP tapered broad-area amplifierswith monolithically integrated waveguide lens for high-powerapplications

A 1.48-μm tapered broad-area semiconductor laser amplifier with a monolithically integrated waveguide lens as demonstrated. The gain saturation characteristics of the tapered amplifier were examined. A maximum output power of 300 mW and a 3-dB saturation power of 200 mW under quasi-CW conditions were obtained from the amplifier without the waveguide lens. Output power of 200 mW was obtained with a broad emission spectrum of ~30 nm when the device was used as a superluminescent diode. The amplified output was focused to a single lobe by the monolithically integrated aspheric waveguide lens, which may be useful for efficient coupling of the output into a single-mode fiber     

High power, diffraction-limited emission from monolithically integrated active grating master oscillator power amplifier (lasers)

A novel monolithically integrated master oscillator power amplifier with a distributed amplifier/grating output coupler is demonstrated which emits 370 mW in a single-frequency diffraction-limited beam without any form of active phase control. The distributed amplifier/grating output coupler results in a guided mode power that saturates along the direction of propagation, providing a uniform carrier density to preserve the flatness of the radiated phase front.<>     

平均功率近2 W的被动锁模皮秒掺镱光纤激光器

报道了一个三级主振荡功率放大(MOPA)结构的瓦级皮秒光纤激光器.第一级利用半导体可饱和吸收镜(SESAM)和光纤光栅组成线性腔,构建了一个低功率的被动锁模掺Yb3+光纤激光器,其最大平均输出功率为9.2 mW,作为整个激光器的种子源;第二级采用单模掺镱光纤放大器对种子光进行预放大,得到108 mW平均输出功率;第三级采用带树状耦合器的双包层掺镱光纤放大器进行功率放大,获得了1.9 W平均输出功率.得到的脉冲脉宽36 ps,中心波长1064 nm,重复频率29.6 MHz,峰值功率1.8 kW,相应的单脉冲能量为61 nJ.实验中观察到种子源输出光谱中有一个凹陷,这是由于光纤光栅反射率过高并且带宽较窄引起的.     

A 4-terminal wide-band monolithic amplifier

A bipolar monolithic amplifier is described which achieves 18 dB gain, 725 MHz-3 dB bandwidth and 4.4 dB noise figure. The circuit is housed in a 4-lead TO-46 package, consumes 180 mW of DC power and requires no external components. Input and output impedances are matched to 50 /spl Omega/ with VSWR less than 1.5 across the band. A high-power version of the circuit consumes 1 W of DC power and gives 152 mW output power at 200 MHz.     

A 77 GHz FMCW radar transmitter with reconfigurable power amplifier in 65 nm CMOS

A frequency modulated continuous-wave (FMCW) radar transmitter in 65 nm CMOS is presented. The transmitter consists of one FMCW signal generator, one reconfigurable power amplifier and bias circuits. FMCW chirp signal comes from a sigma-delta modulated fractional-N phase-locked loop (PLL) with an integrated digital triangle-wave generator to control the output division-ratio of the sigma-delta modulator. A four-way power combining power amplifier is employed to improve the output power with a reconfigurable output power to satisfy different detection distance requirements. The measured results show that the chirp bandwidth achieves 2 GHz, from 76 GHz to 78 GHz, and the power amplifier achieves 13.1 dBm output P1dB with 8.1% PAE. The power amplifier and FMCW signal generator consume 228 mW and 56 mW power, respectively, with a 1.0 V power supply. The core die area is only 2.6×0.88 mm².     

High output power from an efficient praseodymium-doped fluoridefiber amplifier

A praseodymium doped fluoride fiber amplifier (PDFFA) exhibiting efficient operation in both the large- and the small-signal regimes is described. The amplifier, based on a high NA fluoride fiber, exhibited a maximum small-signal gain of 29 dB and a low-pump small-signal. efficiency of 0.13 dB/mW. In the saturated regime a maximum output power of 212 mW was achieved. In this format, the signal-out versus pump-in characteristic, exhibited a slope efficiency of 30%, representing the most efficient conversion from pump to signal yet reported. Detailed spectral characterization reveals small-signal gain in excess of 20 dB over a wavelength range of almost 50 nm and in excess of 100 mW of saturated output available over a 30-nm wavelength range     

一种高效单相电源Ⅰ类线性音频功放的设计

采用SMIC0.18μm3.3V CMOS工艺,实现了单相电源Ⅰ类线性音频功放的设计。为了提高AB类功放的效率,设计了一种新型结构的Ⅰ类线性音频功放,并理论推导了它的效率。Ⅰ类音频放大器中的电源转换器能根据输入音频信号连续调节AB类功放的功率电源电压以减小功率管上的压降。为了使单相电源下PMOS和NMOS功率管功耗同时得到优化,设计了增益变化的信号处理电路。输出级采用桥式结构,并由三级运放构成以提高线性度。测试结果表明,该功放向8Ω阻性负载提供功率在小于270mW范围内时,总谐波失真与噪声之和小于0.45%,最大效率达到70%;功率在100mW范围内时,效率比AB类提高了一倍,且测试效率曲线与理论推导吻合。     

A Low Distortion and Low Dissipation Power Amplifier with Gate Bias Control Circuit for Digital/Analog Dual-Mode Cellular Phones

A power amplifier operating at 3.3 V. has been developed for CDMA/AMPS dual-mode cellular phones. It consists of linear GaAs power MESFET's, a new gate bias control circuit, and an output matching circuit which prevents the drain terminal of the second MESFET from generating the harmonics. The relationship between the intermodulation distortion and the spectral regrowth of the power amplifier has been investigated with gate bias by using the two-tone test method and the adjacent channel leakage power ratio (ACPR) method of CDMA signals. The dissipation power of the power amplifier with a gate bias control circuit is minimized to below 1000 mW in the range of the low power levels while satisfying the ACPR of less than ?26 dBc for CDMA mode. The ACPR of the power amplifier is measured to be ?33 dBc at a high output power of 26 dBm.     

GaAs HBT wideband matrix distributed and Darlington feedbackamplifiers to 24 GHz

The designs and performances of a 2-24 GHz distributed matrix amplifier and 1-20 GHz 2-stage Darlington coupled amplifier based on an advanced HBT MBE profile that increases the bandwidth response of the distributed and Darlington amplifiers by providing lower base-emitter and collector-base capacitances are presented. The matrix amplifier has a 9.5 dB nominal gain and a 3-dB bandwidth to 24 GHz. This result benchmarks the highest bandwidth reported for an HBT distributed amplifier. The input and output VSWRs are less than 1.5:1 and 2.0:1, respectively. The total power consumed is less than 60 mW. The chip size measures 2.5×2.6 mm². The 2-stage Darlington amplifier has 7 dB gain and 3-dB bandwidth beyond 20 GHz. The input and output VSWRs are less than 1.5:1 and 2.3:1, respectively. This amplifier consumes 380 mW of power and has a chip size of 1.66×1.05 mm²      

5.7 GHz low-power variable-gain LNA in 0.18 /spl mu/m CMOS

A variable-gain low-noise amplifier (LNA) suitable for low-voltage and low-power operation is designed and implemented in a standard 0.18 /spl mu/m CMOS technology. With a current-reused topology, the common-source gain stages are stacked for minimum power dissipation while achieving high small-signal gain. The fully integrated 5.7 GHz LNA exhibits 16.4 dB gain, 3.5 dB noise figure and 8 dB gain tuning range with good input and output return losses. The LNA consumes 3.2 mW DC power from a supply voltage of 1 V. A gain/power quotient of 5.12 dB/mW is achieved in this work.     

S波段超宽带固态功率放大器的研制

本文结合一款新研制的S波段超宽带固态功率放大器,介绍了超宽带固态功率放大器的设计理论和方法,根据砷化镓场效应晶体管的小信号S参数和I-V曲线,用微波仿真软件对功率管的输入、输出阻抗匹配电路及其偏置电路进行优化仿真设计.通过制作并测试此放大器,验证了该设计方法的可行性.最后,给出了测试数据,它在2GHz～4GHz的频带范围内,输入功率为40mW时,输出功率大于20W,带内功率起伏小于1.5dB.     

瓦级输出全光纤结构2.0μm掺铥皮秒脉冲光纤激光器

研制了高功率全光纤结构2μm波段掺铥皮秒脉冲光纤激光器。该激光器采用了主振荡功率放大(MOPA)结构设计,种子源采用790nm的多模半导体激光器作为抽运源、双包层掺铥光纤作为激光增益介质、半导体可饱和吸收镜(SESAM)作为锁模器件,从而实现了重复频率为10.4MHz的皮秒激光脉冲输出,其最大平均输出功率为15mW。种子源经过一级掺铥光纤放大器后,获得了1.1W高平均功率输出,相应的单脉冲能量高达105nJ,激光脉冲宽度为9ps,峰值功率为11.6kW。此时测得激光脉冲的中心波长为1963nm,3dB光谱带宽为0.5nm。     

Nd/sup 3+/-doped single mode fibre superfluorescent source with 320 mW output power

A diode array pumped Nd/sup 3+/-doped superfluorescent fibre source with 320 mW output power and a 4.6 nm FWHM bandwidth centred at 1058 mu m is reported. The device is prevented from lasing off reflected light from Rayleigh backscatter by seeding an Nd/sup 3+/-doped fibre amplifier with a primary superfluorescent source of moderate power.<>     

Stimulated Raman amplification of 1.6-μm-band pulsed light inoptical fibers

A synchronous Raman fiber amplifier is proposed which is pumped at a wavelength around 1.55 μm by output pulses from an erbium-doped fiber amplifier. This arrangement achieves an output optical peak power exceeding 200 mW and a 3-dB net gain bandwidth of 33 nm around 1.66 μm. The Raman fiber amplifier is useful for 1.6-μm-band OTDR as it can be used in live maintenance of optical transmission networks     

High-speed multiple-quantum-well optical power amplifier

A multiple-quantum-well optical amplifier is used at 8 Gb/s with high input power such that the average gain is compressed by 2.6 dB. Under these conditions, the output signal level is 35 mW and there is negligible intersymbol interference (ISI) penalty at the receiver. This is possible because of a rapid (7 ps) gain recovery process in the amplifier. A conventional semiconductor amplifier operating at a similar level of gain compression shows 2 dB ISI penalty     

Analysis of monolithic integrated master oscillator poweramplifiers

An analysis of a novel, monolithic integrated master oscillator power amplifier (M-MOPA) is presented. The M-MOPA consists of a DBR master oscillator which injects power into a linear chain of amplifiers and detuned second-order grating output couplers. The analysis self-consistently includes amplified spontaneous emission buildup and residual reflections throughout the amplifier stages. It predicts that output powers in excess of 1 W can be expected from a single-lateral-mode waveguide multistage amplifier less than 1 cm in length, injected with less than 15 mW of input power. In addition to the signal gain of >25 dB, the signal-to-noise ratio at 1-W output exceeds 15 dB. Because of the small reflections associated with the grating output couplers, and gain saturation by the injected signal, the amplifier self-oscillation threshold is suppressed to current densities above 15 kA/cm²     

A 77-100 GHz power amplifier using 0.1-μm GaAs PHEMT technology

A wideband MMIC power amplifier at W-band is reported in this letter. The four-stage MMIC, developed using 0.1 μm GaAs pseudomorphic HEMT (PHEMT) technology, demonstrated a flat small signal gain of 12.4±2 dB with a minimum saturated output power (Psat) of 14.2 dBm from 77 to 100 GHz. The typical Psat is better by 16.3 dBm with a flatness of 0.4 dB and the maximum power added efficiency is 6% between 77 and 92 GHz. This result shows that the amplifier delivers output power density of about 470 mW/mm with a total gate output periphery of 100 μm. As far as we know, it is nearly the best power density performance ever published from a single ended GaAs-based PHEMT MMIC at this frequency band.     

一种900-MHz 20-mW CMOS功率放大器的设计

提出了一个工作电压为3V，工作频率900MHZ，输出功率为20mW的高效率CMOS功率放大器。为了达到设计目标，文章采用了一些特殊的方法，包括三级放大结构，级间的调谐匹配和层叠差分结构。