新颖运放驱动OCL功率放大器

在音响电路中,将集成电路运放用于音频功率放大的驱动段,已不鲜见。这种设计大大地简化了驱动电路,给制作者带来了方便。 但集成运放电路的典型接法,输出信号的幅度比较小,因为它的电源电压均处于±18伏以内,其电压输出幅度也不会超过±15伏,显然用它来驱动工作于射级状态的推挽功率管,负载上得到的电压也就被限制在这个范围内了,从而限制了集成电路在大功率功放电路中的应用。     

RX1500大功率功率放大器

BAL RX1500型H级功率放大器是一台采用MOTOROLA（摩拖罗拉）大功率三极管作双对称驱动,不失真单边功率高达1500W/8Ω的演出级大功率放大器。RX1500具备低噪音信号路径和高电流设计,减低磁场泄漏的环形变压器用于降低电压的嗡嗡声和噪声,以及多级能量变换器可得到高瞬态反应能力和低失真率,这些优点组成了现有的最佳模拟放大器设计标准。     

平衡式E/F类功率放大器的设计与实现

为了解决功率放大器设计过程中存在的效率低和输入/输出端回波损耗较大的问题,设计了一种工作频率为1.5 GHz的平衡式功率放大器。通过采用3 dB定向耦合器对射频信号进行分配及合成,大大降低了输入/输出端的驻波系数,并将逆F类功率放大器的谐波控制网络引入E类功率放大器的匹配电路中。使用ADS对晶体管进行负载牵引和源牵引,得到晶体管的输入/输出阻抗,同时结合晶体管的寄生参数,在输出匹配电路中对二次谐波、三次谐波分别进行开路和短路处理,且为了进一步提高功率放大器的工作性能,在输入电路结构中抑制了二次谐波。选用GaN HEMT器件CGH40010F晶体管,利用ADS软件进行电路仿真,并采用Rogers4350b高频板材制作该功率放大器的实际测试电路板。仿真优化和实测表明：在输入功率为28 dBm时,该功率放大器的输出功率为41.54 dBm,漏极效率为76.99%,功率附加效率（power additional efficiency,PAE）达到73.59%,输入/输出端驻波系数小于2,同时具有160 MHz的高效率带宽,且最大输出功率较单管功率放大器提高了3 dB。实测结果与仿真数据有一定的误差,但仍有较好的一致性,满足设计指标要求,验证了设计方法的可行性。该设计方法具有效率高和回波损耗低的优势,提高了功率放大器的设计效率,使它在当今高效绿色节能的射频微波通信系统中具有广阔的应用前景。     

影响真空溅射用射频电源特性因素的研究

研究了用于真空溅射沉积射频电源的功率转换效率和频率稳定性的影响因素,分析了E类功率放大器和射频驱动级电路的工作特性。推演了最大输出功率公式,运用matlab对其归一化处理,得出最优占空比;在最优占空比条件下,根据射频电源功率放大器对射频驱动级电路的要求,设计了射频驱动级电路,提高了射频电源功率输出频率的稳定度。经电路实验测试,其结果显示,波形规整、稳定。     

电子管功率放大器中的倒相电路

在电子管推挽功率放大器中,功率放大级需要一对大小相等,相位相反的驱动信号,这就需要设置倒相电路,它在放大器中起着非常重要的作用。倒相电路的种类较多,工作性能也不尽相同,它直接影     

EP-CPA401电影院功率放大器电路简析

功率放大器的作用是将前置放大器输出的声频信号进行放大，并推动扬声器发声。在立体声电影重放技术中，是将解码、均衡后的各路音频信号进行放大。对功率放大器的要求是高效率、低失真、大功率、高保真，确保声音的重放有足够的功率，并能如实地反映音频信号的音质与音色。掌握功率放大器的各项技术性能，是正确选择与使用功率放大器的必要条件；懂得功率放大器的电路原理是检     

30MHz-90MHz线性功率放大器的研制

研究和设计射频功率放大器,具有较高的线性度,同时又能实现高功率的稳定输出。着重对射频功率放大器的性能进行分析研究,指出提高功放的线性度的方法;仿真该功率放大器并给出射频功率放大器的硬件电路设计;最后对射频功率放大器进行测试,其性能指标完全达到系统设计要求。     

30MHz-512MHz宽带功率放大器的研制

功率放大器是射频前端中的关键部件，宽带是目前功率放大器的主要发展趋势。根据宽带功率放大器的设计原理，采用推挽结构晶体管，前馈线性化技术，传输线变压器和微带混和匹配电路，利用ADS进行仿真设计，成功的设计出一款宽带功率放大器。实现了多倍频程带宽、确保带内增益平坦、驻波小、线性范围和动态范围大。通过仿真和测试，得到较为理想的结果。     

米波Ⅲ段宽带功率放大器

利用推挽LDMOS，通过采用传输线变压器宽带匹技术，研制出一种米波Ⅲ段宽带功率放大器。文中给出了测试结果放大器的性能指标良好。     

6C33C-B无输出变压器单端功放实践

6C33C-B系俄制低内阻、低电压、大电流三极管,较6N5P,6N13P,6AS7,6AS7G,6AS7GT,6NA3P,6080,6H5C等三极管内阻还要低,不少胆机爱好者将6C33C-B灵活运用于无输出变压器推挽功率放大器中,以省却输出变压器的“瓶颈”作用,并能节省成本及减小机体重量。此种作法出声不成问题,但6C33C-B用于推挽功率放大一是管子配对困难,二是     

Cache Memory Design for Single Bit Architecture with Different SenseAmplifiers

Most modern microprocessors have one or two levels of on-chip caches to make things run faster, but this is not always the case. Most of the time, these caches are made of static random access memory cells. They take up a lot of space on the chip and use a lot of electricity. A lot of the time, low power is more important than several aspects. This is true for phones and tablets. Cache memory design for single bit architecture consists of six transistors static random access memory cell, a circuit of write driver, and sense amplifiers (such as voltage differential sense amplifier, current differential sense amplifier, charge transfer differential sense amplifier, voltage latch sense amplifier, and current latch sense amplifier, all of which are compared on different resistance values in terms of a number of transistors, delay in sensing and consumption of power. The conclusion arises that single bit six transistor static random access memory cell voltage differential sense amplifier architecture consumes 11.34 μW of power which shows that power is reduced up to 83%, 77.75% reduction in the case of the current differential sense amplifier, 39.62% in case of charge transfer differential sense amplifier and 50% in case of voltage latch sense amplifier when compared to existing latch sense amplifier architecture. Furthermore, power reduction techniques are applied over different blocks of cache memory architecture to optimize energy. The single-bit six transistors static random access memory cell with forced tack technique and voltage differential sense amplifier with dual sleep technique consumes 8.078 μW of power, i.e., reduce 28% more power that makes single bit six transistor static random access memory cell with forced tack technique and voltage differential sense amplifier with dual sleep technique more energy efficient.     

An analysis of AC controlled push-pull magnetic amplifier with compensating voltage

An equivalent circuit analysis of an ac controlled push-pull magnetic amplifier is performed, which is compensated with a transistor switching circuit [1] in order to overcome the negative feedback action by the gating induced EMF. The modes of the operation of this new push-pull magnetic amplifier circuit are made clear for cases of various degrees of compensation. The theoretical formulas on both the steady-state control characteristics and the transient time constant are derived. Moreover, the steady-state control characteristics and the transient time constant are calculated for several values of compensating voltage. The results obtained show good agreement with the experiments.     

声学放大器对热声发动机性能的影响

对声学放大器的声功传输能力以及其对热声发动机性能的影响进行了实验研究,发现声学发大器只有在一定条件下才能提高热声发动机的输出压比,当末端阻抗减小时其放大能力也减小.声学放大器本身也是一个声学阻力部件,如果仅以负载引出功计算热声发动机的效率,声学放大器在输出端负载阻抗较大时能够提高系统热效率,当负载阻抗减小后,它将使发动机的热效率急剧降低.     

Analysis and design of high-efficiency variable conduction angle doherty amplifier

The Doherty amplifier was first proposed to improve the efficiency under output power back-off using the technique of load-line modulation of a `carrier? amplifier through a `peak? amplifier. By varying input bias of the peak amplifier along with load of the carrier amplifier at low drive levels, different topologies of the Doherty amplifier are distinguished. An analytical analysis that determines the optimum output performance of these topologies in terms of output power, efficiency and output power back-off ensuring a near-peak efficiency is developed. The presented comprehensive analysis considered for variation of conduction angle of the peak amplifier biased class C. New design equations of the analysed topologies are derived. A realisation at a central frequency of 1.9 GHz using GaAs field effect transistor (FET) devices of a Doherty amplifier topology is reported. In this topology the carrier operates (at low drive levels) into load impedance 5/2 times larger than its optimum. Power-added efficiency of 61.8% is measured at P/sub 1dB/ of 25.9 dB m and 33.2% is measured at 9 dB back-off from P/sub 1dB/.     

一种用于多标准接收机的宽带低噪声放大器

设计了一种应用于软件无线电接收机的300kHz～1.6GHz宽带低噪声放大器,适用于数字广播、数字电视和定位导航等系统.该放大器采用噪声抵消结构以降低输入匹配器件在输出端所产生的热噪声和闪烁噪声,能够同时实现输入阻抗匹配和噪声优化.对采用中芯国际(SMIC)0.18 μm RF CMOS工艺实现的芯片的测试结果表明,3dB带宽为300kHz～1.6GHz,最大增益S21为16.7dB,输入反射系数S11小于-7.4dB,最小噪声系数为2.3 dB,输入参考的1dB增益压缩点为-11.6dBm,功耗为14.4mW,芯片面积为0.49mm2.     

一种降低D类功率放大器开关噪声的设计

传统D类功率放大器因特有的开关噪声对水下电子设备的信号接收、通信控制和信号传输等电信号产生很大的干扰,限制了D类功率放大器在水下电子设备中的广泛应用针对这一现象,首先阐明了Σ-Δ调制的D类功率放大器降低开关噪声的原理,然后对传统调制方式和Σ-Δ调制方式的D类功率放大器进行原理分析,并在Simulink软件中进行仿真对比。仿真结果表明,传统D类功率放大器在开关频率处的开关噪声能量高,Σ-Δ调制的D类功率放大器的开关噪声能量分散在一定的带宽内,并且开关噪声能量峰值低于传统D类功率放大器。     

基于改进型匹配网络的宽带高效率E类功放的设计

为了解决E类功放工作带宽过窄的问题,对E类功放的输入、输出匹配网络提出了一种改进方案.该方案中输出匹配网络采用微带线结构与切比雪夫低通匹配网络相结合的方法,在较宽的工作带宽内有效地抑制了谐波;并采用阻抗变换方法设计了含闭式解的宽带带通输入匹配网络,明显增强了输入匹配网络设计的灵活性.利用该方案,同时采用多谐波双向牵引技术得到功率管的最佳源阻抗和负载阻抗,基于CGH40010F功率管设计了一款应用于L波段的宽带高效率E类功放.测试结果表明,在输入功率为28dBm,漏极偏置电压VDS=28V,栅极电压VGS=-3.3V时,在整个L波段频率范围内漏极工作效率大于65%,最高达到83%,输出功率为39~41.1dBm,增益为11~13.1dB,增益平坦度为±1dB.这一结果验证了该改进方案的有效性,使得E类功放具有宽带宽、高效率的性能.     

Gain and noise figure enhancement of Er+3/Yb+3 co-doped fiber/Raman hybrid amplifier

An Er/Yb co-doped fiber/Raman hybrid amplifier (HA) is proposed and studied theoretically and analytically to improve the gain and noise figure of optical amplifiers. The calculations are performed under a uniform dopant and steady-state conditions. The initial energy transfer efficiency for Er/Yb co-doped fiber amplifier (EYDFA) is introduced, while the amplified spontaneous emission (ASE) is neglected. The glass fiber used for both Er/Yb and Raman amplifiers is phosphate. Different pump powers are used for both EYDFA and RA with 1 μW input signal power, 1 m length of Er/Yb amplifier and 25 km length of Raman amplifier (RA). The proposed model is validated for Er/Yb co-doped amplifier and Raman amplifier separately by comparing the calculating results with the experimental data. A high gain and low noise figure at 200 mW Raman pump power and 500 mW Er/Yb pump power are obtained for the proposed HA as compared with the experimental results of EYDFA, Raman amplifier and the EDFA/Raman hybrid amplifier.