新型开关型三端稳压器K78XX1500及K78XX-1000系列

搞过稳压电源的人一般都熟悉78XX系列三端线性稳压器。由于该系列输出5～24V各种标准电压,输出电流有100mA、500mA及1000mA三种品种,并且电路简单、保护功能完善及价格便宜,因此得到及其广泛地应用。     

RECOM系列稳压器(一) 开关型三端稳压器R-78××-0.5

78XX 系列稳压器是一种三端线性稳压器,由于它的系列性好(有不同的各种标准电压输出、有三种不同电流输出)、输出噪声电压低、价位低。虽然是几十年的老产品,但不断地在改进,在市场上仍有极大的销售量。线性稳压器的调整度工作干线性状态,当输入电压与输出电压之差较大时,其调整度的损耗较大,其效率较低。另外,在输出电流大时需加散热片,增大了 PCB 面积。所以78XX 系列仅适用于市电供电的电子产品,不适用于便携式产品。     

小体积高效开关式三端稳压器K78M系列

K78M系列是一款超小体积高效开关式三端稳压器,是针对目前市面上78系列三湍稳压器、LDO、K78系列等产品的完美升级。     

RECOM系列稳压器(四) 高输入电压的三端稳压器R-78HBXX-0.5系列

<正> R-78HBXX-0.5系列是 RECOM 公司推出的新器件,其是一种高输入电压、非隔离式开关型 DC/DC 变换器,封装成三引脚稳压器模块。最高输入电压可达72V,输出固定电压从3.3V 到24V 形成系列,输出电流可达0.5A(24V 输出为0.3A)。     

RECOM系列稳压器(三) 开关型三端稳压器R-78BXX-1.5

<正> R-78BXX-1.5是 RECOM 公司推出的一款新型开关型三端稳压器模块(直流DC/DC 转换器),设计用来替代线性型三端稳压器78XX 系列,它适用于便携式仪器的应用。78XX 系列三端稳压器是大家熟知的电源器件,它有不同的输出电压(如5V、6V、9V、1 2V、15V、18V 及24V)、不同的输出电流(1.5A、500mA 及100mA(500mA     

新一代高效开关式三端稳压器——K7805-500

K7805-500为MORNSUN即将推出的新一代高效开关式三端稳压器,该产品为非隔离稳压单输出型DC- DC,超宽输入电压范围:约6.5～32 V,输出电压5 V(今后将陆续推出1.5 V,1.8 V,2.5 V,3.3 V),额定输出电     

带短路保护的开关型稳压器

这是一个简单可靠的开关型稳压电路,电源的输入电压范围是25～40V,输出电压为24V,最大输出电流可达2A。一旦输出短路,输出电流可被立刻切断。     

K78xxT-500系列高效率贴片型开关稳压器

MORNSUN（金升阳）在新一代高效开关式l三端稳压器K78xx-500产品线基础上努力优化突破,率先推出国内首款SMD塑封表贴型高效开关稳压器K78xxT-500系列,实现了K78系列的SMD表贴化,满足了客户布板、体积方面的难题,将帮助工控、电力、仪表等多个行业应用客户实现真正的生产自动化,适用于各类手持设备。     

东芝TA78DSxxF系列新型稳压器应用

<正> TA78DS××F系列是新型正电压输出的三端稳压集成电路,其最大输出电流为30mA,具有低压降(小于0.3V)和小等待电流(0.6mA)、内置限流、过热、过压、输入电压极性接反和瞬间过压保护功能,采用了 SOT—89封装结构,体积小巧,是电池供电的电子产品的首选稳压器。     

1．5A开关式三端稳压器

K78XX-1500系列是MORNSUN公司推出的一款全球最新1．5A开关式三端稳压器,产品功耗极小,无需接任何散热片即可提供1．5A输出电流,是针对目前市面上78系列三端稳压器、LDO、K78系列等产品的功率升级。     

三端集成稳压器扩流方法分析

以LM317K进行电流扩展为例介绍了三端集成稳压器的3种扩流方法,即晶体管扩流、电阻扩流和并联扩流。通过扩流解决了三端集成稳压器输出电流由于受限而不能满足设计要求的问题。给出了3种扩流方法的具体电路连接及原理分析。对LM317K设计的不同方案的扩流电路均使用Multisim V10软件进行了仿真,从仿真结果可以看出3种扩流方法的可行性和正确性。通过对3种扩流方法的分析和比较,给出了各自适用的场合和使用的注意事项。在实际应用中,可根据扩流的大小和使用的三端集成稳压器的型号来选择合适的扩流方法。     

关于空调控制器三端稳压管的失效原理的分析与研究

三端稳压管是空调控制器常用元器件,主要作用是直流电压的转换、稳定.三端稳压管内部晶元为半导体材料,实际生产过程中常出现静电类的损伤,并且会影响整个空调控制器正常工作.因此,对于三端稳压管的失效原理的分析研究尤为重要,它可以帮助我们从根源上解决失效问题.本文针对失效的三端稳压管做详细分析,根据失效原理,总结三个优化方向:1、提升稳压管内部受损器件的抗静电能力;2、稳压管内部增加一个电阻,用于防止静电损伤的;3、在稳压管输入端增加一个电容,用于消除静电.     

Y型接法的新型三点式振荡器的设计与研究

利用对偶原则构造了一种新型的三点式振荡器。通过对电路结构的抽象化处理,得到了关于环路增益的Y参数算法,从而使环路增益的计算得以获得简便有效的表达。将文献[10]中相量形式关于起振条件的要求,应用在电路上,仔细考察了其中的计算与证明的细节,从中得知(φT(ω)/ω)ω=ω1的符号具有不依赖于元件参数具体数值的恒定性。这一电路具有比常规三点式振荡器更为丰富的工作组态,但每种组态临界起振时对于元件参数的要求又是简单的。最后,相关分析结论得到了仿真试验与硬件电路实验两方面的检验。     

New single-stage PFC regulator using the Sheppard-Taylor topology

This paper describes a new usage of the DC/DC converter developed by D.I. Sheppard and B.E. Taylor in 1983 for achieving high power factor and output regulation. This converter may be viewed as a cascade of a modified boost stage and a buck stage, with the two stages sharing the same active switch. Two possible operation regimes are described. In the first regime, the converter's input part, which is a modified boost converter, operates in discontinuous mode, and the output part, which is a buck converter, operates in continuous mode. In this regime, high power factor is naturally achieved, and the output voltage is regulated by duty-cycle modulation via a simple output feedback. In the second regime, the input part operates in continuous mode, and the output part operates in discontinuous mode, with duty-cycle modulation maintaining a high power factor and frequency modulation regulating the output. Some comparisons between the Sheppard-Taylor converter and conventional boost and buck cascade are given in the paper     

三端集成稳压电源的布焊及故障分析

三端集成稳压电源是大学必修课《电装实习》课程的重要内容之一。根据已有的电装教学经验,分析三端集成稳压电源的基本工作原理,介绍稳压电源的布焊过程和测试过程,详细介绍学生在完成稳压电源后可能出现的各种故障,并提供了切实有效的解决方法。经过实践验证,这些过程进一步提升了学生的电路原理分析能力、仪器设备(示波器、万用表)在实际电路测试中的操作和使用能力,提高了实习效率,也为电子组装爱好者提供了解决此类问题的经验。     

InP基三端太赫兹固态电子器件和电路发展

随着微电子技术的飞速发展,半导体器件的截止频率已经进入到太赫兹频段,太赫兹电路的频率特性得到极大发展。以固态器件为基础的太赫兹电路的工作频率进入到THz频段。本文重点介绍InP基双极器件和场效应器件的发展以及在太赫兹电路和系统中的应用。     

New high efficiency 500 kW tetrodes for short wave broadcast

Two 500-kW tetrodes, developed for shortwave broadcast service using computer-aided design (CAD) techniques are presented. The two tubes are similar, one having pyrolytic graphite grids and the other Y-3 grids. The tubes are interchangeable and have similar operating parameters. Cooperation between transmitter designers and tube designers facilitated the fulfilling of requirements established by the Voice of America for it's new generation of efficient shortwave international broadcast transmitters. Tubes are now operating in the model 420B transmitter at frequencies between 3.9 and 26.1 MHz at the Voice of America site in Greenville, North Carolina. The tubes operate interchangeably as the power amplifier tube, or the pulse duration modulator tube, and they have multiphase water-cooled anodes rated at 400 kW, low internal inductance and capacitance, mesh-thoriated tungsten cathodes, and two choices of grids, either platinum-zirconium-coated molybdenum wire or laser-machined pyrolytic graphite     

Characterization and modeling of three-terminal heterojunction phototransistors using an InGaP layer for passivation

Fabrication, characterization, and modeling of three-terminal (3T) heterojunction phototransistors (HPTs) using an InGaP layer for passivation (called P-HPTs) compared with similar nonpassivated devices (called NP-HPTs) were reported. Effects of the base passivated by the InGaP layer on devices optical and electrical performance were investigated. In addition to improving the dc current gain in the small current regime, the photocurrent (I/sub ph/) and responsivity from the p-i-n diode formed by the base, collector, and subcollector are also enhanced in a P-HPT. The measured optical gains are 45 and 27 for a P- and an NP-HPT under 8.62-/spl mu/W optical injection operated as a two-terminal (2T) device with a floating base. When the base bias is applied from a voltage source, both 3T P- and NP-HPTs exhibit degraded optical gains. Although a voltage source applied to the base can be used to push the operating point of a heterojunction bipolar transistor to a higher collector current where the current gain is higher, only a small portion of the photocurrent generated within the base-collector region is injected across the base-emitter junction to be amplified. When the base of an HPT is biased using a current source, the I/sub ph/ and enhanced dc current gain mainly determine both collector photocurrent and optical gain. Thus, a P-HPT biased using a current source shows the best optical performance. Furthermore, the conventional Ebers-Moll equivalent-circuit model was extended to provide simulated results in good agreement with experiment.     

One-dimensional three-terminal thyristor modelling at high current densities and stable common gate configuration

One-dimensional modelling of a thyristor, in common base (gate) configuration and the absence of ohmic base resistance removed the inherent instability of the device and enabled the variation of current gains of the constituent transistors to be calculated to very high current densities in conjunction with a host of other parameters. The model employs a Gaussian impurity profile coupled with a combined SRH and Auger recombination term and includes variable mobilities (impurity and c-c scattering as well as electric field dependence). Reverse bias across the central junction of up to 20 V offered no undue difficulties in modelling. The high current flow in excess of recombination requirements in the base regions was rendered harmless by being allowed to pass unhindered out of the gate terminal. This resulted in the anode current exceeding numerically the cathode current with the sum of d.c. current gains having crossed what under different configurations would constitute an instability threshold.     

Discrete-time parametric amplification based on a three-terminal MOS varactor: analysis and experimental results

This paper discusses discrete-time parametric amplification based on large-signal operation of a three-terminal MOS varactor. The principle of operation is described in detail and analytical estimates of performance are derived. Detailed measurements are reported for a prototype implemented in standard digital CMOS technology. It is demonstrated that the technique can be used to provide micropower, low-gain, low-noise, large-signal amplification.