P波段100W（CW）硅大功率平衡晶体管的设计

本文介绍了采用网状发射极图形结构、浓硼扩散发射极镇流电阻以及用输入端内部网络匹配和平衡结构器件组装形式研制出的硅大功率器件，该器件在２２５～４００ＭＨｚ频率下输出功率１００Ｗ，增益７．５ｄＢ，效率５５％。     

Transistor input distortion and emitter degeneration

In the design of class A transistor amplifiers it is desirable to be able to predict and control the amount of distortion produced by the nonlinearity of the transistor input characteristic. This note presents an extension of a previously published method, to include the effects of emitter degeneration. The result provides a convenient means of determining the degenerations required to reduce the second-harmonic distortion to a given level.     

An experimental study of distributed effects in a microwave bipolar transistor

Conventional microwave transistors are normally considered to operate as a single lumped circuit element. That this is only an approximation has been accommodated in the past by the use of an equivalent circuit including some inductance to correct for the finite size of the contact metallization. The effect of this inductance can drastically change the properties of the transistor when the size of the device becomes a significant part of an electrical wavelength. To study this form of behavior, a transistor with an electrical length on the order of one eighth of a wavelength was constructed. When tested in a suitable circuit, feedback effects involving the metallization inductance caused the transistor to produce four times more stable power gain than would be expected from a conventional transistor having the same area. Amplifiers designed using the new transistor and an equivalent conventional transistor had equal gain-bandwidth products. Other circuit properties of the transistor were observed to be significantly modified, the emitter lead inductance becoming an insensitive parameter while the base lead inductance became very critical. The measured properties of the transistor were found to be in good agreement with theoretical predictions.     

A comparison of the GaAs MESFET and the AlGaAs/GaAs heterojunctionbipolar transistor for power microwave amplification

The study is normalized by constraining the devices to specific application: 1-W RF output power at 10 GHz. It is shown that the power gain and thermal resistance are higher and input impedances lower for the heterojunction bipolar transistor (HBT). Because of the higher thermal resistance, the operating temperature is significantly higher for the HBT, limiting the CW power output from the device. If the device area is increased to reduce the power density, then the input impedance (common emitter) will be proportionally reduced, making input matching much more difficult     

Parasitic extraction methodology for insulated gate bipolartransistors

This paper presents a methodology for extraction of the electrical package parasitics of insulated gate bipolar transistor power modules using simple electrical measurements. Non-idealities of device performance in zero-voltage and zero-current switching are exploited to obtain the parasitic collector and emitter inductance. Simple impedance measurements are performed to extract gate inductance and resistance. The extraction methodology is validated by comparing two-dimensional numerical simulation results including package parasitics with measured data. A close match between the two indicates the robustness of the extraction procedure     

A NOVEL Ku-BAND LOW NOISE AMPLIFIER WITH HEMT AND GaAs MMIC

A novel Ku-band low noise amplifier with a high electron mobility transistor (HEMT)and a GaAs monolithic microwave integrated circuit (MMIC) has been demonstrated. Its noisefigure is less-than 1.9dB with an associated gain larger than 27dB and an input/output VSWRless than 1.4 in the frequency range of 11.7-12.2GHz. The HEMT and the microwave series in-ductance feedback technique are used in the first stage of the amplifier, and a Ku-band MMIC isemployed in the last stage. The key to this design is to achieve an optimum noise match and a min-imum input VSWR matching simultaneously by using the microwave series inductance feedbackmethod. The B J-120 waveguides are used in both input and output of the amplifier.     

Cross modulation and nonlinear distortion in RF transistor amplifiers

In order to avoid untractable calculations, the transistor four-pole is assumed to be short-circuited for ac at its output. Furthermore, the internal impedance of the signal source is assumed to be zero. First the nonlinear distortion effects in a grounded base intrinsic transistor are calculated. Then, the formulas are reverted to a grounded emitter intrinsic transistor, taking into account the extrinsic base lead resistance. They are confirmed by measurements of third harmonic distortion and of cross modulation. The measured curves of cross modulation vs collector bias current show a sharp minimum. This unexpected effect is explained by an extension of the theory, which takes into account previously neglected terms. The explanation is successfully tested by experiments. Comparisons with cross modulation in amplifier tubes are made.     

Analysis, design, and optimization of InGaP-GaAs HBTmatched-impedance wide-band amplifiers with multiple feedback loops

The realization of matched impedance wide-band amplifiers fabricated by InGaP-GaAs heterojunction bipolar transistor (HBT) process is reported. The technique of multiple feedback loops was used to achieve terminal impedance matching and wide bandwidth simultaneously. The experimental results showed that a small signal gain of 16 dB and a 3-dB bandwidth of 11.6 GHz with in-band input/output return loss less than -10 dB were obtained. These values agreed well with those predicted from the analytic expressions that we derived for voltage gain, transimpedance gain, bandwidth, and input and output impedances. A general method for the determination of frequency responses of input/output return losses (or S₁₁, S₂₂) from the poles of voltage gain was proposed. The intrinsic overdamped characteristic of this amplifier was proved and emitter capacitive peaking was used to remedy this problem. The tradeoff between the input impedance matching and bandwidth was also found     

下一代移动通信LTE中功率放大器芯片设计

基于0.18μm SiGe BiCMOS工艺,设计了一种应用于下一代移动通信3GPP LTE TDD2.6 GHz频段(Band38)的射频功率放大器(PA)芯片。射频功率放大器采用共发射极3级级联的全差分结构,提高了输出电压摆幅,减小了功率晶体管的集电极电流,且降低了寄生的键合线电感。在预放大级和中间放大级、功率级中分别设计了电阻偏置和有源偏置两种偏置电路以提高线性度性能,并通过MOS开关管实现功率控制功能。测试结果表明:在2.57～2.62 GHz工作频段内,正向增益S21大于30.5 dB,输入回波损耗S11和输出回波损耗S22分别均小于-13 dB,功率增益大于31 dB,输出1 dB压缩点功率达28.6 dBm,功率附加效率为18%。     

A 6-b 12-GSamples/s track-and-hold amplifier in InP DHBT technology

This paper presents a 6-b 12-GSample/s track-and-hold amplifier (THA) fabricated in an InP-InGaAs-InP double heterojunction bipolar transistor (DHBT) technology. The THA is intended for the front end of a high-speed analog-to-digital converter in a digital-based electronic polarization-mode dispersion compensation circuit for a 10-Gb/s optical receiver. With a high-speed switched emitter follower and clocked track-to-hold transition operation, it shows the signal bandwidth over 14 GHz and features a total harmonic distortion (THD) compatible with 6-b operation with input frequency of 6 GHz and a sampling frequency of 12 GHz. The THD increases better than -23 dB with a 12-GHz input signal of 1 V/sub pp/, corresponding to a 4-b resolution, under a differential clock of 12 GHz.     

晶体管非线性失真分析

本文从器件物理和结构上提出双极型晶体管非线性失真模型。模型包含8个参量:(1)有效基区展宽效应;(2)发射极电流集边效应;(3)基区电导调制效应;(4)发射结电阻的非线性效应;(5)发射结电容的非线性效应;(6)集电结电容的非线性效应;(7)寄生电容的非线性效应;(8)电流放大系数和雪崩倍增效应与电压的非线性关系。利用Taylor级数展开分析各模型参数,并编制了计算程序,定量计算了互调失真与工作频率、发射极条宽、基区宽度、发射极线电流密度,基区掺杂浓度等重要参数的关系。计算结果与实验结果基本吻合。     

Surface and geometry effects on large signal base input voltage and input resistance of junction transistors

A design theory for large signal base input voltage and input resistance of junction transistors is presented with emphasis on the effect of surface recombination and transistor geometry. Two-dimensional distributions of minority carrier density and electric field are obtained for the separate portions of the base region. These distributions are then expressed in terms of emitter current and are used to derive expressions for the large signal base input voltage and resistance. The dependence of carrier distribution on surface recombination velocity and transistor geometry is illustrated by curves. The theory is corroborated by a series of experiments carried out with p-n-p power transistors. The parameters varied are surface recombination velocity (by baking), emitter diameter, base ring diameter, dice thickness and base region resistivity. The measured base input voltage and resistance are plotted and compared with calculated values based on the theory presented. Good agreement is found between calculated and measured values. The results deviate in several interesting respects from the values predicted by the small signal or low injection level theory. Based on this theory, design considerations for the large signal input voltage and input resistance are discussed.     

Sinusoidal Burst Generator for Auditory Evoked Response Research

A simple stimulator has been devised in which sinusoidal signals in the audio range are linearly modulated to generate tone bursts of controlled duration and shape for auditory research. The stimulator comprises a transistor differential pair modulator whose differential collector voltage is the product of the voltage applied at a base (sine wave input) and the emitter current (varied by the modulating waveform). A trapezoidal generator is provided for the modulating waveform. The output is greater than 60 dB above noise and switching transients and the ON-OFF ratio is greater than 60 dB up to 50 kHz. The frequency response is flat to 50 kHz, and there is no appreciable distortion. The trapezoidal generator has equal rise and fall times which are independent of the flat-top duration.     

Comparison of hot electron and related amplifiers

It is proposed that novel amplifiers be compared with each other and with existing amplifiers on the basis of as many figures of merit as are calculable. The bipolar transistor; field-effect transistor; Schottky-emitter, space-charge-limited-emitter, and tunnel-emitter, metal-base, hot-electron amplifiers are compared with respect to frequency cutoff and maximum frequency of oscillation. Using reasonable ground rules for the comparison, the amplifiers rank (with respect to frequency cutoff) in the order: Schottky emitter, bipolar transistor, space-charge-limited emitter, and tunnel emitter. With respect to maximum frequency, the amplifiers rank in the order: Schottky emitter; space-charge-limited emitter; tunnel emitter and bipolar transistor equivalent; and field-effect transistor.     

硅低温低频低噪声双极晶体管的分析与设计

对硅双极晶体管低频噪声的本征与非本征两种分量进行了系统的理论分析，并研究了各自的温度特性，在此基础上，设计并研制出一种多晶硅发射极低温低频低噪声晶体管，其等效输入噪声电压。     

DC boosting effect of active bias circuits and its optimization for class-AB InGaP-GaAs HBT power amplifiers

In this paper, dc sourcing capability (DSC), which is a very important consideration in design of active bias circuits for power amplifiers based on bipolar technologies, will be explained. The nonlinear effect of bias circuits on the dc sourcing characteristics has been analyzed with simplified circuits for power amplifiers using the Volterra series. The analysis shows that the second-order distortion generated by a bias buffer transistor can boost bias level of the RF transistor to compensate finite DSC available in the absence of this effect. The bias-level boosting due to RF injection can be optimized by tuning the value of a series resistor between the emitter of the buffer transistor and the base of the RF transistor. Amplifiers with different series resistors have been implemented and tested with an IS95-B code-division multiple-access signal at the cellular band (824-849 MHz). The experimental results verify that a circuit-level optimization for the second-order distortion of the bias circuits is very important for optimizing the linearity and efficiency of the HBT amplifiers.     

高灵敏度穿通型异质结光电晶体管

报导了一种带有独特隔离环结构的宽禁带发射区平面穿通型光电晶体管（ＧＲ－ＰＴＨＰＴ），在弱光信号下具有高灵敏度。器件工作时基区全部耗尽，基极电流基本为零，输出噪声电流大大下降，使光电增益提高了一个量级以上。已研制成的ＧａＡｌＡｓ／ＧａＡｓ穿通型光电晶体管（发射极直径φ＝４μｍ）。在５Ｖ工作电压下，对０．８μｍ，１．３ｎｗ和４３ｎｗ弱光的光电增益分别为１２６０和８１０８。折合到输入端暗电流为０．８３ｎＡ。     

New implementation of high linear LNA using derivative superposition method

New implementation of a high linear low-noise amplifier (LNA) using the improved derivative superposition (DS) method is proposed. The input stage is formed by two transistors connected in parallel. One transistor is biased in the strong inversion region as usual and another one is biased in the moderate inversion region instead of the weak inversion region, thus allowing a feasible source degeneration inductance at the sources of the two transistors to achieve a good input impedance matching and low noise figure (NF) while keeping high third-order input intercept point (IIP3) improvement with the DS method. The new implementation has been used in a 0.18-μm CMOS high linear LNA. The measured results show that the LNA achieves +11.92 dBm IIP3 with 9.36 dB gain, 2.25 dB NF and 7.5 mA at 1.8 V power consumption.     

Two-dimensional nonisothermal carrier flow in a transistor structure under reactive circuit conditions

The current density and temperature distribution in a bi-polar power transistor operating in the switching mode under transient conditions has been computed as a function of circuit environment. A modeling was done of the turnoff of the transistor in a circuit containing resistive and inductive elements. Of particular interest was the study of the local current and temperature distribution achieved in the transistor during turnoff in a circuit with a large inductance; in the process of shutoff this inductance maintains the transistor collector current at a high value as the collector junction undergoes avalanche multiplication due to the high voltage induced across this junction by the inductive load. The length of time that the transistor remains in the high-current high-voltage mode during the turnoff transient determines the extent of current crowding and local heating in the device. The method of computation was to solve numerically the electrical carrier flow as well as Poisson's and the heat-flow equations in a two-dimensional model of an n⁺-p-n-n⁺transistor structure, as a function of time. The electrical boundary conditions on the emitter, base, and collector contacts were determined by considering the transistors interaction with its electric circuit environment. This interaction was calculated at each step in time, in an iterative fashion, as the transistor was turned off by extracting current from its base lead. The study permits the evaluation of a given bipolar transistor design with respect to current crowding, heating, and impact ionization in switching circuits containing inductive loads.     

基于多β晶体管的双边沿D触发器及其应用

通过对多 β晶体管的开关特性分析 ,结合其射极输入、射极输出、高速工作等特点设计了二值双边沿 D触发器 ,计算机模拟表明该设计具有正确的逻辑功能和高速的工作特性。文中还介绍了双边沿 D触发器在时序电路中的应用。