complex的博客

From: Compoundsecmiconductor.net IOP Publishing, the owner of Compound Semiconductor magazine and the compoundsemiconductor.net web site, has ceased publication of the title. Over recent months, IOP Publishing has undertaken a strategic review of its priorities as a learned-society publisher of leading journals, magazines, websites and electronic services. As a result of that review, the company has decided to focus on its core activity of learned journals, which have grown more than fourfold si...

阅读全文>>

I was a little surprised by this report that has Skyworks surpassing RFMD in market share but Strategy Analytics announced that Skyworks has managed to gain the number one position for cellphone PAs according to their research. The rapid growth of handsets has pushed the PA market to $2 billion per year with Skyworks and RFMD relying on the majority of their revenues from this market despite diversification efforts. Both firms and their competitors have invested heavily in new PA products and te...

阅读全文>>

锐迪科微电子(RDA)日前宣布，其应用于地面数字电视接收的高性能射频接收芯片量产，这也是在该领域国内首颗成功上市的芯片，标志着国外芯片垄断国内市场的历史从此改写。该芯片型号为RDA5880，采用CMOS工艺，QFN32 5*5封装，片外器件极少，具备高集成度的特点，支持自动增益控制模式，能够支持目前所有的数字电视广播传输标准(包括 DVB-T、DVB-C、ATSC、DMB-T/H、CMMB等)以及模拟电视标准，支持多波段band III 174M-240M, VHF band 470M-870M。 RDA5808的量产令锐迪科的产品线更加丰富。此前，锐迪科已经成功推出了多款FM、Bluetooth...

阅读全文>>

Korean vendor says it favors performance and reliability provided by SiC substrates over silicon for GaN wireless components.RFHIC says that GaN-on-SiC devices can be competitive with products manufactured on silicon wafers, thanks to economies of scale offered by its strategic partner Cree. “Although GaN-on-SiC is not the cheapest GaN solution, Cree makes it a viable alternative even compared to the most cut-throat LDMOS,” said Kevin Kim, senior international sales manager at RFHIC. Cr...

阅读全文>>

RFMD® develops and manufactures unmatched compound semiconductor technologies and is now offering foundry services for our industry-leading 0.5μm GaN on SiC process. RFMD’s world-class manufacturing scale, supported by the largest III-V factory in the world, enables best-in-class cycle times backed by our on-time shipment pledge. RFMD’s track record as a high-volume, reliable supplier has earned us “preferred partner” status with the industry’s top OEMs while our extraordinary level of cu...

阅读全文>>

Look at the chips in the Palm Pre.              ...

阅读全文>>

转载一篇。 *** 手机射频系统有三个主要零组件，收发器（Transceivers）、功率放大器（Power Amplifier，下简称PA）和天线开关，有时PA包含在前端模块（Front-End-Module，简称FEM）。2G时代的射频系统只占大约1.5美元的成本，3G时代则占大约6-8美元的成本，4G时代则占大约8-10美元的成本，也是手机升级换代成本增加最多的部分。    收发器是手机平台的一部分，通常提供手机基频的厂家都要提供收发器，两者基本上一一对应的关系。诺基亚是个例外，它采用德州仪器的基频，但是却采用意法半导体或英飞凌提供的收发器。不过现在...

阅读全文>>

  看看我已经无聊到了什么地步。整整两天，一个人霸占了整个办公室，做一些很没劲的事情：整理整理读过的书，翻翻硬盘上的资料......一个人的周末，下着雨不能打球，婷儿还没有回来，我还能做什么呢？挺无聊的。 于是，决定梳理一下自己这几年做MMIC/RFIC的知识，画张图直观化，看看自己到底掌握了多少，还有什么欠缺。图是用Smart Draw画的，从半导体材料-->器件-->工艺-->电路设计-->测试封装，为了高度概括，所以只能写一些关键词。也许还有遗漏，不过看上去已经挺庞大的了。在IMECAS读书这几年，尽管没有什么成...

阅读全文>>

1. GaAs 半导体材料可以分为元素半导体和化合物半导体两大类，元素半导体指硅、锗单一元素形成的半导体，化合物指砷化镓、磷化铟等化合物形成的半导体。砷化镓的电子迁移速率比硅高5.7 倍，非常适合用于高频电路。砷化镓组件在高频、高功率、高效率、低噪声指数的电气特性均远超过硅组件，空乏型砷化镓场效应晶体管(MESFET)或高电子迁移率晶体管(HEMT/PHEMT)，在3 V 电压操作下可以有80%的功率附加效率(PAE: Power Added Efficiency)，非常适用于高层(high tier)的无线通讯中长距离、长通信时间的需求。 砷化镓元件因电子迁移率比硅高很...

阅读全文>>

《论语·为政》——子曰：“学而不思则罔，思而不学则殆”。 其意思是：学习而不思考，人会被知识的表象所蒙蔽；思考而不学习，则会因为疑惑而更加危险。最近一段时间埋头苦读，对于这两句话有了更加深刻的理解。每个人或多或少都会患有这两种毛病，从我身边就能找到很多活生生的例证。当然，比起不学也不思来，这两种毛病只能算得上瑕疵。我自己的毛病，更多的是“学而不思”。无论在高中，大学还是研究生中，你都可以发现很多像我这样比较勤奋刻苦的人，但这一类人往往会“劳而无功”，所取得的成绩与付出的辛劳严重不成比例；当然也会发...

阅读全文>>

Chapter 8: Test Questions:  1. What else should be provided at the side of the chips, as well as dc bias pads, to aid decoupling? 2. How much current can a typical probe needle feed onto the chip? 3. What does RFOW stand for, and what are its advantages? 4. How many contacts does an RFOW probe have, and what are they for? 5. What does the calibration do? Answers:  1. A dc pad connected to a through-substrate via, preferably one for each bias supply. 2. 0.5A. 3. Radio Frequenc...

阅读全文>>

Chapter 7: Processing Technology Questions:  1. What is meant by the word monolithic in the MMIC acronym? 2. What is important about the structure of the substrate material? 3. How are the wafers produced? 4. Why is it useful to use a low-conductivity, semi-insulating substrate material? 5. How is the conductivity of a semiconductor increased for the active layers in the transistors? 6. What are the different ways to create an active layer? 7. What are the two common photoresist pro...

阅读全文>>

hapter 6: Layout Questions:  1. MMIC layout data files are built up from lines or polygons? 2. What does hierarchy mean in the context of MMIC layout? 3. Does the MMIC designer construct the layers within the transistors? 4. What is the consequence if critical errors are not spotted before the masks are manufactured? 5. What determines the layout rules? Give two examples. What is the general approach for laying out an MMIC? 6. What do DRC, LVS and ERC stand for? 7. What is the proce...

阅读全文>>

Chapter 5: Design Questions:  1. Which MMIC transistor technology has an operating frequency down to dc? 2. Which MMIC transistor technology is most suited to low-noise mm-wave applications? 3. Which MMIC transistor technology can operate over 100GHz? 4. What is a good figure for the gain per stage in a multistage amplifier MMIC? 5. What range of input match is reasonable to expect for a 10GHz MMIC? 6. What are the dc bias pads usually placed, and what characteristics of their placement are...

阅读全文>>

Chapter 4: Simulation and Component Models Questions:  1. What are the limitations of s-parameter representation of MMIC component elements? 2. How are the individual MMIC components characterized? 3. What is the "lumped-element" approximation? 4. How do the parasitic elements differ from the prime element in an equivalent circuit model? 5. What extra requirements does nonlinear simulation place on the models? 6. Why would an MMIC use 3D EM simulation? 7. What effect will placing a ...

阅读全文>>