[问：jackfjg] 语音经过放大器放大后怎么样才可以消除背景音

[答：Charles_Lee] I suggest you to use the digital signal processing methods to remove the background noise since once the signal and noise mixed together, it very hard to remove from the amplifier. @[02-3-14 上午 10:46:00]

[问：wangzhu1] AD8051允许的最小输入值是多少？他的最小输出值是多少？

[答：Charles_Lee]  @[02-3-14 上午 10:50:18]

[问：fetchstar] 对于一个动态范围达100dB、最小值到10pA的电流信号，有没有合适的放大器可将其转换成电压信号。信号的频率范围从直流到几KHz。该放大器可以有增益控制，但必须有输出说明当前的增益值，以便于对输出信号进行定标。

[答：Charles_Lee] AD8304/05 is the good one for your requirement @[02-3-14 上午 10:52:24]

[问：lijin_as] 3.zener zap trimming vs laser-trimming?

[答：Max_Liberman] laser-burning small amount of resistor with a laser   zener zap-as the current exceeds the zener junction the diode becomes a short and reroutes it through a different path, creating a different proporty. @[02-3-14 上午 10:56:01]

[问：lijin_as] 4.what"s superbeta technology used in AD620?

[答：Eagle_Zhang] 这是ad620的特点： Gain Set with One External Resistor(Gain Range 1 to 1000) Wide Power Supply Range (62.3 V to 618 V) Higher Performance than Three Op Amp IA Designs Low Power, 1.3 mA max Supply Current EXCELLENT DC PERFORMANCE (“B GRADE”) 50 mV max, Input Offset Voltage 0.6 mV/8C max, Input Offset Drift 1.0 nA max, Input Bias Current 100 dB min Common-Mode Rejection Ratio (G = 10) LOW NOISE 9 nV/ÖHz, @ 1 kHz, Input Voltage Noise 0.28 mV p-p Noise (0.1 Hz to 10 Hz) EXCELLENT AC SPECIFICATIONS 120 kHz Bandwidth (G = 100) 15 ms Settling Time to 0.01%  @[02-3-14 上午 10:57:01]

[问：rathaoshen] 请问ADI公司有关宽频弱信号放大的产品有哪些,比其它公司同类产品有何具体的优势?

[答：Charles_Lee] Low noise, wider BW and low cost @[02-3-14 上午 10:58:33]

[问：lijin_as] 5.can u introduce me an preAmp whose input noise<0.3uV,temp drift < 0.005uV/degree,chopping stable,autozero,best working for strain gauge bridge of 120ohm cell.

[答：Wayne_Zhou] Please try AD8551/52/54, AD8571/72/74, and AD8628. You may need to combine different AMPs to reach your parameter requirements, using temparature compensation (at least 3 AMPs). @[02-3-14 上午 10:58:47]

[问：CZHIZHI] 对于一个4~20mA的传感器输入，我应该如何用

[答：Charles_Lee] Please call to (755)378-1959 for more details. @[02-3-14 上午 10:59:54]

[问：shuibing] 能否简要介绍一下电流反馈放大器的原理和使用方法。特别是，该怎样确定应当选用电压反馈放大器，还是电流反馈放大器？谢谢！

[答：Eagle_Zhang] 电流放大器的带宽很宽，可以参考“模拟电子技术”清华 童诗白。 AD603 （VGA）可变增益放大器是电流反馈。 @[02-3-14 上午 11:00:28]

[问：jzw88888] 此新型放大器属于哪一类放大器？它的性能特点是什么？在手机中可 作什么用？

[答：Eagle_Zhang] 我们是在讲我们推出的各种新型放大器，类型很多。当然可以用于手机。请参考www.analog.com @[02-3-14 上午 11:02:21]

[问：高翔] 请介绍一下ADI公司的RF放大器系列。

[答：Wayne_Zhou] Please try AD83xx (AD8302, AD8313, AD8367........). including True RF Amp, Log Amp, and RF detector controller. @[02-3-14 上午 11:03:28]

[问：kexiyong] 变送器很贵，特别是用于水处理的检测仪表上的。据了解，以前的变送器的工作温度漂移很严重，自身工作也不稳定。我的问题是：现在的器件水平是否已经能够开发设计的变送器。在我所关心的领域，廉价的高可靠性的变送器有很大市场。能否给些技术上的提示或指导？多谢。

[答：Eagle_Zhang] 可以用ADuC814/ADuC812/ADuC816(AD＋8052单片机＋DA＋8kFLASH) + AD421/420 (4~20mA变送器) @[02-3-14 上午 11:04:54]

[问：qin] Rail to Rail　放大器的输出采用什么技术达到高的输出电压？其非线性失真如何？

[答：Charles_Lee] Ususally, R-R output stage has much smaller of the voltage drop than the normal amplifier on the output stage.The output stage architecture is to make sure the lowest voltage drop you can get. @[02-3-14 上午 11:07:01]

[问：shcljk_001] 请简要的介绍一下，最近ADI公司的新产品的型号及其主要的应用场合，谢谢！！！！

[答：Eagle_Zhang] AD8021、AD8610、OP1177等， 有很多，请参考www.analog.com @[02-3-14 上午 11:07:27]

[问：eureka] 从技术上讲，AD公司的放大器在解决零点漂移，线性放大频带宽度有何独特的技术？在放大器市场中，AD公司所占的份额有多大？

[答：Wayne_Zhou] Chopping Amp, and linearizing. ADI Amp is the 1st OP Amp supplier, its market share is 17%. @[02-3-14 上午 11:08:43]

[问：ztcg] 请问：      有没有动态增益范围比较大的运放，比如说，从0DB-60DB，而且，不用换档就能实现。是自增益的

[答：Charles_Lee] Yes, Log amplifier like AD8313. @[02-3-14 上午 11:10:06]

[问：LCHDAO] 我想索取ADI公司有关新型放大器的技术资料可以吗？ 单位：西门子信号有限公司工程部　陆臣道 地址：西安经济开发区　凤城二路30号　邮编：710016 电话：029-6522777-318

[答：Charles_Lee] Please contact our office. @[02-3-14 上午 11:11:00]

[问：lijin_as] 2.what"s the significance of SPICE model?

[答：Eamon_Nash] Spice models are used to simulate the operation of an operational amplifier. Generally, they do a very good job of simulating bandwidth, offset voltage, slew rate, input and output swing, stability. Spice models generally do not simulate temperature effects. Some but not all simulate noise. Spice models also do not simulate part to part variation. To use a spice model, you need a simulation program such as Orcad (Orcad now owns P-Spice). @[02-3-14 上午 11:11:43]

[问：xintiaf] 请问贵公司的放大器在带宽和检测弱信号方面有什么突出优势？

[答：Eagle_Zhang] 高精度，宽带，低噪，高速，低偏置电流，低漂移，等。不同型号有不同特点：如 AD8353/8354: 100MHz ~ 2.7GHz AD8304: 160 dB LOG AMP AD8021: 190MHz at G=-10, 2.1nV/sqrt(Hz),2.1PA/sqrt(Hz)  @[02-3-14 上午 11:12:20]

[问：sldz] ADI在数字功率放大器有那些产品。此类放大器的带宽可以从DC--几十KHz吗？它是否可用于单端接地的负载，且相对于浮地负载的效率或功率是否会下降？

[答：Wayne_Zhou] No at present. @[02-3-14 上午 11:12:26]

[问：jokewolf] 50MHz 以上的线性放大器之选择

[答：Wayne_Zhou] Please try AD8051/61/55/57. Or you can try Log Amp AD83xx. @[02-3-14 上午 11:14:13]

[问：wjpw31] 光纤放大器怎么样解决了衰减对光网络传输速率与距离的限制？原理是什么？

[答：Charles_Lee] Used EDFA, please call (755)378-1959 for more details. @[02-3-14 上午 11:15:03]

[问：Jin] If I want to choose a OP with ultra low noise , low input bias current and very small offset voltage, what ADI can offer?

[答：Max_Liberman] The New FET input amplifers AD8065 or AD8610 pending on the speed that you need. @[02-3-14 上午 11:15:04]

[问：wchao] Is ADI in the RF Amplifier business?

[答：Eamon_Nash] Yes, ADI makes amplifiers for RF applications. Typical devices are AD8353, AD8354, AD8367, AD8343, AD8313, AD8346 and AD8347. For a very good over view, go to analog.com and select "RF and Communications" @[02-3-14 上午 11:16:23]

[问：jokewolf] 请教：有没有一款有效分辩率在13位以上、低功率、低电压（3V）、高速（转换速率在1.2MSPS以上）的能同时进行双通道采样的ADC。

[答：Eagle_Zhang] AD7866： 2.7V~5.5V, 12Bit 1MSPS dual SAR ADC.Dual, 10 MSPS AD10410: Dual，10MSPS，14bit. - Channel-channel isolation, >80dB - DC-Coupled Signal conditioning included Selectable Bipolar Input Voltage Range (+/- 0.5V, +/- 1.0V, +/- 2.0V) Gain flatness up to Nyquist: < 0.2dB 85dB Spurious-Free Dynamic Range Straight binary output format 3.3 / 5V CMOS-Compatible Output Levels  @[02-3-14 上午 11:18:38]

[问：lvchangzhi] 在要求需要较高的电压转换速率（V/us）、低失调、高精度、高速时应选择哪一类集成运放？设计运放电路系统时的电磁干扰（EMI）如何考虑？

[答：Wayne_Zhou] AD80xx can be the choice, but dependant on your actual requirement, please refer selection guide to choose. About EMI, you need to use small packaging AMP, and PCB design is very important. @[02-3-14 上午 11:18:58]

[问：Coody Kuo] How to solve current drifts caused by temperature increasing

[答：Eamon_Nash] There are a number of options 1. Choose a operational amplifier that has very low temperature drift. 2. Use some kind of a heating element that will heat up the device package but which will keep the temerature high but constant. This is however an expensive solution. 3. If the temperature drift is predictable, you maybe could use a temperature sensor on your board. Using the reading from the temperature sensor, you can maybe compensate for the change in voltage from the amplifier. @[02-3-14 上午 11:21:17]

[问：lyuchun] 我想知道RF放大器的器件有那些特点？信噪比好不好？我公司有RF品摇控产品，想知道你公司有那些类型？多谢！

[答：Eagle_Zhang] RF AMP: 高速，宽带，低噪声。 参考刚才介绍的AD8021，AD8353。 AD8302可测增益与相位。  @[02-3-14 上午 11:21:34]

[问：Jin] I know bipolar OP have lowest noise, FET OP have lowest input bias current and chopper OP have lowest offset voltage. Could you please provide a circuitry to combine these advantages togather?

[答：Max_Liberman] Our New Family of FET Amplifers provide these functions in one amplifer.  The have the low input bias current (1pA) along with low noise (6.5nV/sqrtHz) and low offset of (0.1mV).  Please refer to AD8065. @[02-3-14 上午 11:21:37]

[问：rapids] 对于信号传输过程中有段1米长的传输线形式，接收端是用仪用放大器呢？还是用差分放大器为好？

[答：Charles_Lee] Wideband, high current output amplifier is good one for your application. @[02-3-14 上午 11:23:17]

[问：rapids] 大的输入阻抗容易耦合噪声，所以尽量避免用正相放大的形式，是不是这样？

[答：Wayne_Zhou] it"s dependant on your design requirement. Generally, non-inverting Amp can cause low CMRR, which is not proper for high accuracy design. Also high input impedance make it not so useful for some situation. @[02-3-14 上午 11:24:34]

[问：zm1012] I want to know if it is the ADI"s fashion to provide more features and high switching frequency to make smaller size products?

[答：Marco_Baratta] ADI is always working towards improving their designs based on customer and market needs.  Higher speed (switching frequency) products like op-amps are in development.  Smaller size products (based on feature size) depend upon if the design can be made with smaller geometries.  Pure digital designs can (usually) be scaled to smaller feature size.  Analog and mixed-signal designs, do not always scale to smaller feature sizes. Therefore, smaller designs are not always done for these products.  For DSP products (digital intensive designs), smaller geometries are being looked at. @[02-3-14 上午 11:24:36]

[问：sheng] 失调电压在仪表放大器中如何保持到最低限度？在应用上有何注意的吗？

[答：Eagle_Zhang] 选用低失调电压精密仪表放大器，可加调零电路。注意要温度漂移小的。如：AD620，AD622，AD623， 或考虑 AD8551 （自调零），AD8605。 @[02-3-14 上午 11:24:37]

[问：cuixh] 请问在开关电源的误差反馈中用那种类型的放大器比较适合?

[答：Eagle_Zhang] 通用的即可，可考虑响应速度快的。 @[02-3-14 上午 11:26:21]

[问：qyjhappy] 我曾经用过AD623，请问ADI现在有没有噪声更小的同类型器件。

[答：Eagle_Zhang] AD622（12nV/sqrt(hz)）和AD620（13nV/sqrt(hz)）噪声略小于AD623 （35nV/sqrt(hz)）。 @[02-3-14 上午 11:28:37]

[问：hj.chen] AD公司的运算放大器是否可以在滤波电路中使用

[答：Eagle_Zhang] 可以。如AD8021。 @[02-3-14 上午 11:29:54]

[问：dvssy] 讲座中提到放大器根据性能不同而有很多种类，那么，在用户设计中除了对放大器型号的选择外，在电路设计和实验测试时还有哪些注意。因为很多情况下，在实验时参数达不到手册中所标注的指标。

[答：Wayne_Zhou] At first, you need strictly follow the suggestion on datasheet, or refer to evaluation board design, refer to application note (you can find from our website www.analog.com). Other devices around AMP is also very important. PCB layout and PCB material can also influence the performance of the AMPs. @[02-3-14 上午 11:29:54]

[问：robin] Could you advice China Local Office Information ?

[答：Charles_Lee] Shanghai: (21)6426-7009, ShenZhen: (755)378-1959 @[02-3-14 上午 11:30:54]

[问：Texas] 请解释一下Rail-Rail的含义。谢谢！

[答：Eagle_Zhang] 请听培训教材。 @[02-3-14 上午 11:32:21]

[问：zm1012] 我急于了解新型放大器在低温下的响应度是否会降低，如何补偿？谢谢。

[答：Wayne_Zhou] Yes, usually it is. First choice is to use high performance chips, such as military parts. Second is to choose high slew rate chips. @[02-3-14 上午 11:33:39]

[问：sony] ADI在视频放大方面有没有什么低价位的产品

[答：Charles_Lee] AD8051/52/61/62 is good for your application. @[02-3-14 上午 11:35:09]

[问：wjpw31] AD622是否还需要再用分立器件设计仪表放大器？

[答：Eagle_Zhang] 不需要。参考AD622datasheet and application note, 或者seminar materails on www.analog.com, 点击tech support, 后点击seminar materail。 @[02-3-14 上午 11:36:36]

[问：freespirit] 我实验领域的应用环境的干扰特别大，请问新型放大器的抗干扰性能如何？是否适合强干扰环境

[答：Wayne_Zhou] The performance on anti-interference of chips is improving day by day. But it depends on design, such as filter or shielding, to decrease the innterference. @[02-3-14 上午 11:37:58]

[问：zm1012] 新型放大器在低温下的响应度是否会降低，如何补偿？

[答：Eagle_Zhang] 大部分有工业级： -40 ~ 85"C。  @[02-3-14 上午 11:39:51]

[问：wudizeng] 我如何与你们销售工程师联系?

[答：Wayne_Zhou] First visit our website www.analog.com, or our distributors in China (Excelpoint, Chinatronic, Arrow, and Future), you can find the telephone number on our website. @[02-3-14 上午 11:40:48]

[问：zb7401] 放大器增益的带宽如何恰当的选择？如信号为10khz~100Mhz.

[答：Wayne_Zhou] Usually, select AMP with bandwith 1.5 times of your highest signal frequency. @[02-3-14 上午 11:42:56]

[问：zm1012] 我急于了解新型放大器在低温下的响应度是否会降低，如何补偿？谢谢。

[答：Max_Liberman] As the temperature changes the amplifer bandwidth will slightly change, in either direction.  The only way to compensate for the possible change in temperature is to provide enough headroom in the desgn.  We typically provide minimum  bandwidth specifications on the datasheets. @[02-3-14 上午 11:42:58]

[问：gme] 我想知道，用AD公司的运放设计频率合成器的环路滤波器时，与同类的产品对比，我可获得什么指标的好处？

[答：Eagle_Zhang] 低噪，低漂移。 @[02-3-14 上午 11:43:34]

[问：qin] ADI放大器片内有温度传感器吗？

[答：Charles_Lee] No, usually, the ADC or Microconverter has the temperature inside. But we provide some temperature sensor with voltage or current output. Like TMP36/37. Please check to our web site. Other relative parts are are ADM102x and ADM103x and ADuC812/824. @[02-3-14 上午 11:46:05]

[问：freespirit] How can I get the detail infomation about ADI products?

[答：Charles_Lee] Please contact our local office or visit our web site @http://www.analog.com to down-load complete data sheet. @[02-3-14 上午 11:47:43]

[问：guodagang] 请问adi的放大器在有线电视行业是否有应用?

[答：Marco_Baratta] ADI has a portfolio of op amps for CATV applications such as Cable Modems, Cable Telephony and Cable Set Top Boxes.  All these products are DOCSIS compatible. Our released products include the AD8325 with 0.75dB step size, over 60dBmV output power and very low distortion performance.  The AD8326 cable driver with 67 dBmV output power and 0.75dB step size for Cable Telephony applications.  The AD8322 with 6dB step size for use with Broadcom chipsets.  All these products datasheets are availble at www.analog.com under Broadband components. Also, we are now sampling the AD8328 which is a low cost driver for Cable Modems, and Set Top Boxes.  This part offers very low cost, 60dBmV output power, 1dB step size and DOCSIS compatibility with distortion performance.  This part will be released in September.  Prelim datasheets are available now.  Please contact me for more information marco.baratta@analog.com @[02-3-14 上午 11:49:32]

[问：greatface] If I want to use AD8313 to detect WCDMA signal, how can I select the integral circuit?

[答：Max_Liberman] I would recommend to use the new AD8363 detector.  The AD8362 is a true RMS responding power detector.   For specifications please refer to the AD8362 perliminary datasheet on the web. @[02-3-14 上午 11:51:10]

[问：freespirit] 我实验领域的应用环境的干扰特别大，请问新型放大器的抗干扰性能如何？是否适合强干扰环境。

[答：Charles_Lee] Use differential input/output amplifier such as AD8130/31/32/38 can solvesome of the issues. @[02-3-14 上午 11:51:17]

[问：LIUCL] 请问adi公司的模拟信号乘法器可以用于高频信号的功率测量电路吗？

[答：Eagle_Zhang] 最好是用AD8302，它是基于模拟乘法。 FEATURES Measures Gain/Loss and Phase from VLF to 3 GHz Dual Demodulating Log Amps and Phase Detector Input Range –62 dBm to –2 dBm in 50&#8486; System Accurate Gain Measurement Scaling (30 mV/dB) Accuracy Typically < 0.5 dB Accurate Phase Measurement Scaling (10 mV/deg) Accuracy Typically < 1 degree Measurement/Controller/Level Comparator Modes Operates from Supply Voltages from 2.7 – 5.5 V Stable 1.8 V Reference Voltage Offsetting Output Video Bandwidth DC to 30 MHz APPLICATIONS RF/IF PA Linearization Precise RF Power Control Remote System Monitoring and Diagnostics Return Loss/VSWR Measurements Log Ratio Function for AC Signals  @[02-3-14 上午 11:53:16]

[问：LIUCL] 请问测量几千周到几百千周信号源的输出功率用什么型号的集成电路比较好？

[答：Wayne_Zhou] It depends on your signal magnitude and accuracy. Please contact local ADI office or distributors, giving more information. Suggest using digital circuit to calculate the output power. @[02-3-14 上午 11:57:29]

[问：wchao] Is this seminar focused on every aspect of amplifier technology?

[答：Eamon_Nash] No. This seminar gives a brief overview of operational amplifiers. For more detailed information on op-amps and amplifiers in general, I would suggest that you go to www.analog.com, then select Technical Support, then Seminar Material. There is good information on amplifiers in the Practical Analog Design Techniques and High Speed Design Techniques seminars @[02-3-14 下午 12:00:28]

[问：周莹] do you have divice to replace device OP160 which has enable pin?

[答：Max_Liberman] We do not have a single current feedback amplifer with a disable.  The AD8063 is voltage feedaback with a little less slew rate, but it does have a disable pin.  Pending on how many amplifiers your system needs the AD8013 (triple) has simmilar specifications as the OP160. @[02-3-14 下午 12:03:10]

[问：lchzhang] 请问高速度放大器、RF放大器和宽带放大器有什么区别？

[答：Wayne_Zhou] High speed Amp means slew rate higher than 100v/uS. RF speed Amp means working frequency higher than hundreds of MHz. Board bandwidth Amp means board bandwidth, but usually relatively low SR and working frequency. @[02-3-14 下午 12:03:30]

[问：zm1012] I want to know if it is the ADI"s fashion to provide more features and high switching frequency to make smaller size products?

[答：Eamon_Nash] I"m not sure exactly what you are looking for when you say switching frequency. As a company, ADI is always striving to make faster devices with extra features. @[02-3-14 下午 12:04:52]

[问：lihaitao] 目前，我想对PIN管的输出电流进行放大，不知道采用哪种运放比较合适？我要求的动态范围是：50~70dB

[答：Charles_Lee] LOG amplifier like AD8313. @[02-3-14 下午 12:05:54]

[问：zm1012] 放大器中最快的反应速度是多少？编程为什么格式？

[答：Eagle_Zhang] AD8353/AD8354很快。 AD603用电压控制增益（－10～41dB， 90MHz BW）， AD8323用串行口控制增益（Gain Programmable in 0.75 dB Steps Over 53.5 dB） AD8367 是500MHz －2.5 dB to +42.5 dB VGA。 AD8353 FEATURES Fixed gain of 20 dB Operational Frequency to 100 MHz to 2.7GHz Linear output power of 8 dBm Input/Output internally matched to 50 ohms Temperature and power supply stable Noise figure 5 dB Power supply 3 V or 5 V APPLICATIONS VCO buffer amplifier General Tx/Rx amplification Power amplifier predriver Low power antenna driverFUNCTIONAL BLOCK DIAGRAM GAUSSIAN INTERPOLATOR AD8367 FEATURES Broad Range Analog Variable Gain –2.5 dB to +42.5 dB 3 dB Cutoff Frequency of 500 MHz Gain Up and Gain Down Modes Linear-in-dB,Scaled 20 mV/dB Resistive Ground Referenced Input Nominal ZIN   200 On-Chip Square-Law Detector Single-Supply Operation:2.7 V to 5.5 V APPLICATIONS Cellular Base Station Broadband Access Power Amplifier Control Loops Complete,Linear IF AGC Amplifiers High-Speed Data I/O  @[02-3-14 下午 12:06:07]

[问：shingbo] ADI是否有输入带宽大于144Mhz的RF放大器

[答：Eamon_Nash] AD8353 and AD8354 are RF gain blocks that work over a wide frequency range AD8367 is a variable gain amplifier that works up to frequencies of about 500 MHz  @[02-3-14 下午 12:08:50]

[问：fuqiu1] 请问放大器的反馈电路的设计应注意哪些问题？

[答：Wayne_Zhou] 1) input impedance 2) Bandwidth 3) Gain 4) CMRR   Please take care of other devices around the AMP. @[02-3-14 下午 12:08:51]

[问：lijin_as] is an intrumental Amp is a better choice than Op amp in case of working as a differential preamp?

[答：Eamon_Nash] Yes, even though an op-amp is also a differential amplifier, when you connect up the feedback resistors, it effectively becomes a single-ended input amplifier. Instrumentation amplifiers are generally used whenever you have a differential signal which you want to amplify with gains of up to about 1000. @[02-3-14 下午 12:11:16]

[问：lds330] 1。我在多通道数据采集电路中，如何减低通道切换时的抖动？是否可以通过在多路开关（如4051）的输入、放大器的输出之间串联一个合适的电阻将其消除至最小？ 2。AD公司的对数放大器可否运用于单极性脉冲信号的测量？

[答：Eagle_Zhang] 1. Add a buffer to increase the driver ability, use sutaible filter, chose a fast set AMP to driver A/D. Use a serial resistor will decrease the voltage, should adjust gain. 2. Yes. LOG AMP can detect both DC and AC signal. Refer to AD8304/8307/8310 datasheet. @[02-3-14 下午 12:12:19]

[问：zyq558] AD8031/2等等这些用在什么产品上，有什么功能？

[答：Charles_Lee] Low power wide BW applications such as handheld device. @[02-3-14 下午 12:14:43]

[问：freespirit] In our lab. there are very big interference for the environment ,so i want to know the anti-interference properties of your product ? Thanks

[答：Max_Liberman] I am not sure what interference you are refering too.  All of the parts have ESD protection circuitry on the input to protect from static.  As far as the signal interference around the part, it can be minimized by the board layout. One thing to keep in mind is that the amplifer has current loops that are formed around output and power supply pins.  Proper decoupling techniques are essential to minimize lead inductance and that might make the part unstable by lowering the phase margin of the amplifier, especially in high-speed amplifiers.  All of the decoupling capacitance grounds and the Loads must be tied together at one point to minimize the distance that the current needs to travel through ground to complete the loop.  For a more detailed explanation refer to a current datasheet, such as AD8039 on the analog webpage. @[02-3-14 下午 12:16:49]

[问：lanzhoulx] 请问运放配高阻放大微电流信号时经常要考虑高阻的温度特性,贵公司是否有最新生产将运放和高阻集成在一起且温度特性很好的器件?

[答：Eagle_Zhang] Usually the FET input AMP have very high input inpendance. Such as AD8610/8510/8512/8513. AD8610 FEATURES -40"C ~125"C Low Noise 6 nV/√Hz Low Offset Voltage:100  Max Low Input Bias Current 10 pA Max Fast Settling:600 ns to 0.01% Low Distortion Unity Gain Stable No Phase Reversal Dual Supply Operation: V to  V  @[02-3-14 下午 12:18:28]

[问：rapids] 是不是所有的放大电路输出阻抗都很小？比如测量微小电流的I-V转换电路中，尽管一般跨接一个大的电阻，但其输出阻抗还是很小？

[答：Wayne_Zhou] No, not all amplifier circuit has small output impedance. For example, comm-base amplifier has great output impedance.  @[02-3-14 下午 12:18:29]

[问：ljmfree] AD8051允许的最小输出值是多少？

[答：Charles_Lee] 15mV. @[02-3-14 下午 12:19:59]

[问：y2308] 各位专家、主持人好。 请问光纤放大器在以宽带综合数字信息(BISDN)为目标的国家通信网中应用效果、进展情况如何？对我们的工作、生活是否息息相关，有何直接的益处？ 谢谢！

[答：Eagle_Zhang] Yes. EDFA is widely used and very mature in China. @[02-3-14 下午 12:20:24]

[问：rapids] 模拟电路中采用高精度的电阻对性能是否有关键的影响？

[答：Eagle_Zhang] 是，电阻的温度特性也很重要。 可以用仪表放大器减少电阻数量。 @[02-3-14 下午 12:23:07]

[问：sheng] ADI放大器的增益带宽乘积，比如ADN2843能达到多少？高速放大器，RF放大器，仪表放大器，精密放大器和光二极管驱动器对它的要求有何不同？

[答：Eagle_Zhang] ADN2843 is laser driver at 2.5GHz DWDM system.  @[02-3-14 下午 12:25:11]

[问：teilyuan] AD797放大器在高输入阻抗，高增益应用时如何解决噪声，设计时要注意哪些问题。贵公司的代理商有哪些？售价一般为多少？ 还有更好的其它电路吗？谢谢！

[答：Eagle_Zhang] Try to avoid long input line in PCB. Use metail box for shielding. Do not got too much high gain in a single step, otherwise may be cause osc. Only one low noise AMP is need in the first stage if the gain of first stage is high. refer to Noise Figure caculation. @[02-3-14 下午 12:28:15]

[问：bluewind007] what is the best working temperature  fit for the amplifier?thanks !

[答：Max_Liberman] We characterize our amplifers at 25 degrees C, therefore all of the plots on the datasheet are done at that temperature.  We do make sure that amplifers work at temperatures that are defined in the datasheet. Typically the amplifiers are Industrial Grade and work from  -40degC to +85degC.  Please refer to individual datasheet for specific temperature rating.  @[02-3-14 下午 12:28:51]

[问：Sophie Liu] Could you explan the meaning of the word PRA? and what is its abbreviation?Thanks !

[答：Max_Liberman] PRA is Precision Amplifier.  When looking on the web for those specific products refer to Precision Amplifiers page which can be found under amplifiers and linear. @[02-3-14 下午 12:31:31]

[问：ronazhang] 我们过去的方案：在接收机中ADC之前采用的是三极管放大和AGC电路，请问刚才提到的适合后接ADC的运放方案与我们传统方案的性能比较。谢谢

[答：Eagle_Zhang] Our low noise AMP （AD8021， AD603） is suitable for receiver. Hower, if you want a noise figure less than 2, you had better use 分立组件。 AD603 FEATURES “Linear in dB ”Gain Control Pin Programmable Gain Ranges –11 dB to +31 dB with 90 MHz Bandwidth 9 dB to 51 dB with 9 MHz Bandwidth Any Intermediate Range,.g.,–1 dB to +41 dB with 30 MHz Bandwidth Bandwidth Independent of Variable Gain 1.3 nV/√Hz Input Noise Spectral Density 0.5 dB Typical Gain Accuracy  @[02-3-14 下午 12:31:31]

[问：ljmfree] AD603 （VGA）可变增益放大器是电流反馈？

[答：Eagle_Zhang] Yes。 @[02-3-14 下午 12:33:17]

[问：wwh-007] 输入信号为0.01uv级 ,使用什么放大器芯片，产生mv级输出电压。

[答：Eagle_Zhang] What is you bandwidth? Use noise (nV/sqart(Hz)) * sqrt(BW) to caculate the input noise of the AMP.  @[02-3-14 下午 12:36:02]

[问：Sophie Liu] Have you any products instead of the OP Amplifier OP-27(SO08)?

[答：Max_Liberman] Please refer to the the Precesion Amplifer Selection guide which can be found on www.analog.com under amplifiers and linear under precision amplifiers.  There are many low noise precision amplifiers available. @[02-3-14 下午 12:40:44]

[主持人：ChinaECNet] 恭喜您，Flower！经过电脑抽奖您在本次座谈中获得一部数码相机。 恭喜您， longly！经过电脑抽奖您在本次座谈中获得一部MP3播放器。 请网名为Flower，longly的用户与中电网联系(8610-82667550-8005 或 eng@chinaecnet.com)。 @[02-3-14 下午 12:43:17]

[问：]:恒流源和恒压源在应变桥激励是是否可同时应用？

[答：]:You can use either of them

[问：]:"基于强弱电的电磁干扰和隔离放大应如何考虑？"

[答：]:Good ground when PCB design, small package (wafer best), using isolator amplifier, outline shielding.

[问：]:可否介绍一些ADI放大器在仪器仪表中的典型应用？

[答：]:As example: http://www.analog.com/productSelection/signalChains/instrumentation/inst_1.html and http://www.analog.com/productSelection/signalChains/instrumentation/inst_9.html

[问：]:可否推荐一两个用在锁相环有源滤波中的放大器呢？ 该如何应用以确保好的相噪？

[答：]:You can try PLL chips ADF41xx/ ADF42xx directly, which can help on phase noise and package size issue

[问：]:美国模拟器公司(ADI公司) 在中国有无投资计划？效果如何？

[答：]:We've a design center in China, and some university program, third party design house. Good effective.

[问：]:哪一种放大器最具有性价比？

[答：]:It's depended on your application and requirements.

[问：]:那里有培训资料呢?

[答：]:www.analog.com

[问：]:能否推荐种噪声性能好于AD648的双运放?

[答：]:Please try AD885x, or AD706/712/746/822.

[问：]:能否详细介绍一下关于手机上用到的放大器？性能、具体型号、和其它公司相比优势在哪里？谢谢！

[答：]:LOG amplifier like AD83xx, and single-end-differential amplifier like AD8350/8138.

[问：]:你好,我的电路中需要一片音频放大器,音频带宽3.4KHz,请问选用贵公司的那种产品较合适,能得到较高的性价比.

[答：]:If the power is not very big, please refer to ssm2xxx.

[问：]:你们好。宽带光纤放大器技术现在发展的潮流是什么？

[答：]:EDFA is popular, and ADI has some control parts, including power detector, such as AD8310/ 8304, ADC, DAC, also Microconvertor ADuCxxx (with MCU, Flash, ADC and DAC on one chip, as SOC).

[问：]:请给出贵公司放大器在通信产品中的用例。

[答：]:Please refer to the signal chain, which you can find at www.analog.com.

[问：]:请给我ADI各种具体性能和参数好吗?

[答：]:Please go to ADI website www.analog.com, to get relative datasheet.

[问：]:"请简单介绍AD623引脚排列和AD623基本电路结构。"

[答：]:Please refer to the datasheet.

[问：]:请简单介绍新型放大器技术(I)目前的应用范围如何？

[答：]:Such as RF amplifiers, IF amplifiers, including log amplifier, power detector, line driver, (AD83xx), and video buffer AD8079. Some also can be used for optical system. Chopper amplifier has good performance on offset.

[问：]:请简要的介绍一下，ADI公司产品和其它公司的产品比较有什么优势？

[答：]:Log amplifier, and chopping amplifier.

[问：]:请教放大器的低频响应是否可以绝对作到0Hz。

[答：]:surely.

[问：]:请教有关AD620放大器的性能特点?

[答：]:please refer to datasheet, which you can download from www.analog.com.

[问：]:请介绍仪用放大器的特点?

[答：]:high input impedance, high CMRR because of differential input.

[问：]:"请推荐一些用于线路驱动的放大器，输出电流大于500mA，工作频率在40kHz-30MHz."

[答：]:Try AD8016/8017/832x, and we've video line driver 8131/8130.

[问：]:请问,ADI公司新型放大器技术与其它公司相比,有什么独特的优势?

[答：]:Log amplifier, and chopping amplifier.

[问：]:请问，电视广播接收机用中频放大电路，在输入和输出时要考虑阻抗的匹配问题，而放大三极管的放大倍数和中周电感有什么对应关系吗？

[答：]:Please refer to relative IF amplifier design.

[问：]:请问，在用中频放大测试电路测试电子产品时，用相同的测试电路和组件，为什么得到的电子产品性能却不一样？

[答：]:The testing equipments's performance should always be higher than be-tested.

[问：]:"请问：在高频应用中如何消除来自空间的射频干扰"

[答：]:Good ground when PCB design, small package (wafer best), outline shielding.

[问：]:请问：ad812an芯片在+2放大应用中如何消除它的阻尼振荡。

[答：]:need good PCB design, with good ground, with good power supply bypass, and you'd better put ferrite bead, using resistant about 22ohm at input.

[问：]:请问：ADI系列可以用在汽车防盗器上的高频放大电路吗？

[答：]:Surely, you need select parts according to the frequency.

[问：]:请问：ADI在汽车领域是否有所运用？如果有，请说明在什么地方？

[答：]:Especially we've accelerometer ADXL202/105/210/190.

[问：]:请问：AD公司有没有在线可编程、或者程控运放。

[答：]:AD8320, 8321, 8322, 8323.

[问：]:请问：此次讲座都包括哪些类型的放大器。

[答：]:The seminar has two parts, the first part is about basic theory of amplifiers, the 2nd part will be about various amplifiers.

[问：]:请问ADE7755与AD7755以及7755有何区别？

[答：]:ADE7755 is an advanced type from AD7755, more suitable for power energy data collection.

[问：]:请问ADI公司的新型运放与其它厂家相比的性能优势和价格优势，谢谢!

[答：]:Log amplifier, and chopping amplifier.

[问：]:请问ADI公司的仪表放大器除了在精度方面的高性能之外还有什么优点？

[答：]:Low noise, high stability.

[问：]:请问ADI公司有何宽频弱信号放大器,性能怎样?

[答：]:AD8021/22 is wideband low noise OP-Am can use on this applications.

[问：]:请问ADI公司有没有比较廉价的彩电信号放大器？是什么型号？

[答：]:If you mean pre-amplifier of RF, no special part for that.

[问：]:请问ADI公司在中国有何发展？对于在中国的网络和光学研究有什么实用的领域？

[答：]:We've a design center in China, and some university program, third party design house. We've product for ADSL, and optical communications.

[问：]:请问对于0~5mV的线性型号,要做成电压或电流型变送器,有类似于AD693的新的芯片可选吗?

[答：]:No at present.

[问：]:请问贵公司高精度放大器的最大精度，以及高速度放大器的最快响应时间，谢谢！

[答：]:Please refer to AD8628 and AD8014.

[问：]:请问贵公司在音频功放方面主要有什么出色的产品？

[答：]:Try SSM2xxx.

[问：]:请问是否有3.5GHz频率范围的低噪声放大器？

[答：]:At present, 2.7G is highest.

[问：]:请问微转换器的抗干扰性能如何？是否适合工业环境？谢谢

[答：]:Good anti-interference performance, because it integrate ADC/DAC/MCU and interface on single chip, with small package, easy to use. Surely it can be used in industry enviorenment.

[问：]:"请问我能否下载有关运算放大器的产品清单?请问贵公司是否生产高性能的开关电源?"

[答：]:Surely you can download selection guide from www.analog.com. And if you mean switch regulator, the ADPxxxx.

[问：]:请问一下ADI放大器功耗最小的静态、工作时电流分别为多少？

[答：]:op193 and AD8541.

[问：]:请问有没有应用于光发射模块中，具有温度（补偿）自动增益调节的放大器。

[答：]:Try LDD ADN2841/2843, EEPOT ADN2850, TEC controller ADN8830.

[问：]:请问在防雷方面有什么特殊处理?

[答：]:Need special handling with devices around.

[问：]:"请问芯片是否具有USB接口？"

[答：]:No AMP has USB interface, but DSP such as ADSP2192 has USB interface.

[问：]:我公司正在进行局域网升级改造工作，贵公司能提供什么方案？

[答：]:Please contact ADI Local office.

[问：]:当用于单电源时，AD8051的VINmin 与VOUTmin 各是多少？

[答：]:Input Voltage Range: –0.2 V to +4 V;Vout = 25mV to 4.975mV.(VS = +5 V);

[问：]:3月14日由中电网和ADI公司举办的在线座谈的主要内容是什么？

[答：]:You will know while online.

[问：]:AD623带宽是多少?

[答：]:0.8MHz. Please refer to datasheet.

[问：]:AD623的同类型器件的失调电压在仪表放大器中如何保持到最低限度?

[答：]:The AD620's low input bias current of 1.0 nA max is made possible with the use of Superbeta processing in the input stage.

[问：]:AD623的误差源计算方法是怎么样的?

[答：]:Total Error RTI = Input Error + (Output Error/G); Total Error RTO = (Input Error ? G) + Output Error; please refer to datasheet.

[问：]:AD623缓冲输出电路的特性是什么？

[答：]:Please refer to datasheet which can be download form www.analog.com.

[问：]:AD623具有的直流特性是什么？

[答：]:Please refer to datasheet which can be download form www.analog.com.

[问：]:AD623具有优良的CMRR,它的抑制频率是多少？

[答：]:90 dB Min CMRR (G = 10); 84 dB Min CMRR (G = 5) (@ 60 Hz, 1K Source Imbalance).

[问：]:AD623适合哪种供电应用场合？

[答：]:Single and Dual Supply Operation.

[问：]:Single and Dual Supply Operation.AD623与传统三运放结构仪表放大器(例如AD620)的基本电路结构不同之处是?

[答：]:Both AD623 and AD620 are the instrumentation amplifier based on a modified classic three op amp approach. AD623 can assure single or dual supply operation even at common-mode voltages at the negative supply rail, it is rail to rail. AD623 is much cheaper than AD620 for it's noist is slightly bigger than AD620.

[问：]:AD623主要用于哪些范围？

[答：]:Low Power Medical Instrumentation,Transducer Interface,Thermocouple Amplifier,Industrial Process Controls,Difference Amplifier,Low Power Data Acquisition.

[问：]:AD8016放大器是双电源工作的能否改成单电源工作？

[答：]:Set a 1/2 VS vitual ground and use AC couple input and output can work in single VS, but logical input should level shift!

[问：]:AD8367的最大优点有哪些？

[答：]:AD8367 Broad Range Analog Variable Gain –2.5 dB to +42.5 dB, 3 dB Cutoff Frequency of 500 MHz,Gain Up and Gain Down Modes,Linear-in-dB,Scaled 20 mV/dB.

[问：]:ADI的大功率运放的技术特点和与同类其它公司产品比较的优势?

[答：]:I am not sure what's your big power mean? We have less power amplifier. Please contact ADI local office.

[问：]:ADI的新放大器与其它的放大器相比有哪些特点？

[答：]:High speed, low noise & low cost Here we refer to not only one amplifier.

[问：]:ADI公司的放大器主要有哪些型号。

[答：]:Too many, include in-AMP and operation AMP. Please brouse www.analog.com.

[问：]:ADI公司放大器的带宽是多少？

[答：]:AD8353's Operational Frequency from 100 MHz to 2.7GHz with fixed 20dB gain.

[问：]:ADI公司有没有好的PCM CODEC呢？

[答：]:AD73311/73322, mono/stearo 16bit CODEC.

[问：]:adi芯片手册中给出的内置温度传感器是否可以做外界环境温度计使用？如果不能，它测出的温度通常情况下与外界温度差值多大？

[答：]:It can if the self power warm up can be neglected. Use AD7414 (3uW power consuption) I2C bus SOT-23 package is better.

[问：]:"ADI在数字功率放大器的产品与三菱，national等几家大型的公司的产品有何优势？以及采取何种方式来占领市场份额"?

[答：]:We provide the whole signal chain solution.

[问：]:"ADI自己的产品应该形成一种风格，这样才会起到更大的力度。请问ADI现在自己的风格向哪种方向发展呢？"

[答：]:Always provide the newest product such as high speed, low noise & low cost amplifier and high speed DSP. We provide the whole signal chain solution with good technical supporting.

[问：]:ＡＤ公司的运放比其它公司价格偏贵，往往使我们在设计电路时不敢全部采用，贵公司是否考虑过应适当降低价格，以争取更多的市场份额？

[答：]:Some parts are not expensive. We have develop some low cost high speed amplifier.

[问：]:How to enhance the value of CMRR?

[答：]:Choose a right in-AMP, try to be very good match and high signal channel issolation, pay attentation to PCB layout many be helpful.

[问：]:I just want find out what is focus of this seminar.

[答：]:Basical principle.

[问：]:ina128的fL在我的数据采集系统中只有6Hz，原因可能是什么？

[答：]:Sorry, I am not sure what's your question. Please contact ADI local office.

[问：]:RF干扰衰减电路有什么特点？

[答：]:Sorry, not focus in this seminar. Please contact ADI local office.

[问：]:当用于单电源时，AD8051的VINmin 与VOUTmin 各是多少？

[答：]:Input Voltage Range: –0.2 V to +4 V;Vout = 25mV to 4.975mV.(VS = +5 V);

[问：]:电流放大器的带宽有多大？

[答：]:AD8353's Operational Frequency from 100 MHz to 2.7GHz with fixed 20dB gain. I am not sure whether it is current feed back.

[问：]:对于WCDMA基站的射频设计，ADI是否有相应的放大器？

[答：]:Yes. For example, AD8352's operational Frequency to 100 MHz to 2.7GHz with fixed gain of 20dB.

[问：]:对于测量单脉冲信号的线性放大器，脉宽小于2us,幅度在0~500mV ,输出为0~10V,ADI的放大器中有哪些信号可选？

[答：]:Many, choose a fast seting one.

[问：]:对于检测微弱光的线性放大，选择哪种型号？

[答：]:Log AMP is best, say, AD8307 has 92 dB Dynamic Range: –75 dBm to +17 dBm.

[问：]:"对于弱光的检测放大，用于模拟测量，常因为光放大电路的放大倍数过大，造成放大器的不稳定和噪音增大，对此在设计弱光放大器应注意哪些问题？ADI的放大器有无设计参考资料提供？"

[答：]:Use log AMP. Please contact ADI local office.

[问：]:放大电流对电器有什么影响？

[答：]:I am not sure what you mean! Please contact ADI local office.

[问：]:放大器的技术趋势是什么？

[答：]:High speed, low noise & low cost.

[问：]:放大器技术的发展方向？

[答：]:High speed, low noise & low cost.

[问：]:放大器是电流反馈最大可到多少？

[答：]:Please refer to datasheet, which you can download from www.analog.com, or contact ADI local office.

[问：]:光放大器在长途网络中的应用是如何降低成本的？

[答：]:Sorry, not focus in this seminar. Please contact ADI local office.

[问：]:贵公司阿AD202在应用压力变换，进行电磁兼容射频感应电磁场传导抗扰试验，该器件输出在220M不正常，是否与其有关？

[答：]:AD202 has High CMV Isolation:2000 V pk Continuous (K Grade), your issue may cause by stray capacitor. Please contact ADI local office.

[问：]:贵公司的AD202JY在应用中进行射频电磁场传导抗扰度220MHz附近工作不正常，是否和器件调制频率有关？

[答：]:AD202 has High CMV Isolation:2000 V pk Continuous (K Grade), your issue may cause by stray capacitor. Please contact ADI local office.

[问：]:"贵公司的放大器技术产品工作带宽能达到多大?谢谢!"

[答：]:AD8353's Operational Frequency from 100 MHz to 2.7GHz with fixed 20dB gain.

[问：]:贵公司的新型放大器技术较以前有什么提高，与竞争对手相比，有什么优势？

[答：]:High speed, low noise & low cost.

[问：]:贵公司能否提供输出功率为43dB以上、工作频率在20KHz至600KHz这样类型的模拟集成功率放大器电路？

[答：]:I am not sure if you refer to 43dBm? We have less power amplifier. Please contact ADI local office.

[问：]:贵公司是否能向中国用户提供军用级别的器件?

[答：]:Sensitive question!

[问：]:贵公司有技术支持吗？如何联系？

[答：]:We have ADI Shenzhen Office(0755-3781959), Shanghai Office(021-64267009) and Beijin Office, you can also find in www.analog.com.

[问：]:贵公司在音频放大器方面主要有哪些出色的产品?

[答：]:Many, such as OP275, Low Noise: 6 nV/?Hz, Low Distortion: 0.0006% High Slew Rate: 22 V/ms, Wide Bandwidth: 9 MHz. Please brouse www.analog.com

[问：]:如果我用AD8313检测WCDMA的信号，如果选择合适的积分电路？

[答：]:You get need to get the right cut-off frequency for your system. AD8313 data sheet page 11 can provide this information.

[问：]:如果用在W-CDMA上的功率检测，可以使用AD8313吗？ 还是有更好的产品？

[答：]:Yes, Dependent on your dynamic range of the signal. Other choce for LOG amp are AD8314,AD8315.

[问：]:"如何查阅AD8021、AD8610、OP1177等新型放大器资料？在北京有无销售代理？地址？"

[答：]:Please call to Wayne Zhou @ 13511009768 for more detail.

[问：]:如何得到ADI放大器的技术资料？

[答：]:Please contact Wayne Zhou @ 13511009768.

[问：]:如何用运放制作27到15伏或到6伏、1.5安培的稳压电源？

[答：]:Skip.

[问：]:是否有短波频段的RF放大器？

[答：]:Answered already on the web

[问：]:输入信号电压范围为0－20 mv,使用ADUC824,能否做到50,0000精度的电子天平?

[答：]:No, in this voltage range you just can get about 13~14 bits resolution.

[问：]:虽然ADI公司放大器很有名，但是我却不知道，也许更多的人也未曾听说过这个名字。我的问题：ADI公司在宣传上是怎么做的？

[答：]:Thanks so much for the advice. We will doing more seminar and advertisment of the famous magazine to explore our name on the public.

[问：]:微转换器的抗干扰性能如何？

[答：]:It's very good that you can use differntial mode inputs to remove the common-mode noise.

[问：]:我的设计目标是uV的精度，总的放大倍数是500倍，能否推荐合适的前放、放大级型号？谢谢

[答：]:AD855x Zero-offset amplifier is a good candidate.

[问：]:我们有很多光模块产品的客户（武汉-光谷），在发射/接收器中ADI有哪些放大器提供。有什么优势，在向客户推介时ADI能不能有技术的支持。

[答：]:ADN284x as the LDD and ADN2819 as the 2.5G CDR. The advantage is ADI's solution provide more robust temperature stable characterist than our competitor and also lower BER.

[问：]:我使用了一批ADI公司的AD8051，感觉还可以，而且，以后还会大量使用。但是感到不方便的是没有中文资料，既然ADI把中国作为一个主要市场之一，不妨搞一些中文资料，以方便我这样的英文盲使用。

[答：]:Thanks so much for the advice. We will doing the best as we can. If you have any advice to use our chip, please feel free call to our local office.

[问：]:我现在正在做蓝牙无线耳机，但我现在用手机连接时噪音比较大，可以说说什么原因吗?

[答：]:This might cuased by the RF interference. I like to suggest you use a differential mode headphone driver instead of the single-end driver on your system And, Provide a good noie immute LDO on your system also essential. Such as the ADP333x series LDO.

[问：]:我想测量数个pF的电容量，请推荐一放大器。

[答：]:The Instrumentation Amplifer such as AD62x series are good candidates on this application. But usually, you have to use the bridge method to measure it and avoid to direct measurement.

[问：]:我想问该放大技术在仪表应用上的优点。

[答：]:The advantage is provide very high CMRR and noise rejection feature.

[问：]:我需要ADuc814开发产品，不知贵公司何时可提供ADuc814的开发系统？

[答：]:The ADuC814 tool is ready now. Please contact our local sales office.

[问：]:我用AD7711做ad进行热电阻信号测量，三线制接法，但是在使用过程中现场有较大干扰时会造成cpu死机，请问为什么?

[答：]:Please check to your CPU reset circuits or the power supply and maybe the layout is to close to the noise source.

[问：]:线性放大频带宽度有何独特的技术？

[答：]:Ususally, to keep the BW as always high in wide range of the gain setting is very difficult on the voltage feedback amplifier. But you can choice current feedback amplifier on your design. However, you have to very careful on the feedback resistor. Because it is the key part to determine the amplifier's BW.

[问：]:新型放大器的抗干扰性能如何？

[答：]:The specifications on the OP-Amp you can check is the CMRR and PSRR. Those two parameters can help you to get right part on your application.

[问：]:新型运放能否在高阻抗微弱电流信号中使用?

[答：]:Yes, Such as the very low cost AD854x can provides very very low bias current. It's about 10pA on those chips.

[问：]:仪用放大器AD620仪用单电源供电时，REF.端如何处理？

[答：]:The best way is connect to the ADC's Vref pin on this design. But, you still can connect it to ground or a low input impedence DC source.

[问：]:仪用放大器在使用时应注意的问题?

[答：]:The considering orders are: supply voltage, BW, CMRR, PSRR, Vos, Ib, Noise figure, Slew rate, power consumption.

[问：]:"因为14日讲课，所以提前问一个问题。1。我所开发的产品需要使用各种放大器，主要以工业产品为主。涉及普通运放和可编程放大器，可选器件很多。我认为ADI在工业中应用有它的特点，希望给与指点，也希望能提供资料。2。现在正在进行的项目涉及微信号放大（200pV--1uV）,不知是否有合适ADI器件？"

[答：]:The AD855x series OP-Amp are good candidate on your application.

[问：]:由于放大器的种类很多，ADI的产品型号标示有没有分类？如何能比较准确和快速的选用到较为合适的放大器？

[答：]:There is no clear definition for the application on the part numbers. The best way is call to our local sales office for the quick help.

[问：]:有关宽频弱信号放大的产品有哪些？

[答：]:AD805x,AD806x.

[问：]:有没有，0.3$以下的单电源放大器

[答：]:AD8541,AD8531.

[问：]:有没有5PIN的AD8051?

[答：]:Yes, AD8051ART.

[问：]:有没有评价放大器方法的有关资料?

[答：]:Please check our web site for the relative application note or call to our local office for the help.

[问：]:有没有一款有效分辩率为24位、输入信号电压（0－20 mv）、低速的能同时进行双通道采样的ADC。

[答：]:No, But you can use 2 AD7718 or AD7719(one channel 16 bits and another channel 24 bits) on your application.

[问：]:与LM7131相比，AD8051的优是什么？

[答：]:Smaller power consumtion, much wider BW and slew rate.

[问：]:语音经过放大后怎么会产生回音?

[答：]:It could be caused by some external signal paths feed through or the amplifier external circuits design problem.

[问：]:在高速、高精度控制系统中，强电和弱电的隔离技术应主要注意那些问题？

[答：]:Please make sure the return trace on the PCB layout won't cause the high voltage signal influence the low signal. And the power supply should be totally separated. The power supply bypass capacitors should close to the chip's pins as possible.

[问：]:在国内，使用ADI的放大器时如果有问题，应该怎样与你们联系。

[答：]:We have differenent location can serve you. Shanghai@(021)6426-7009, Shenzhen(0755)378-1959.

[问：]:在精密放大电路中是否需要采用高精度的电阻，对性能是否有关键的影响？

[答：]:Yes, dependent on where you use the resistor. For example, if the result is functional of the resistor. Normally, the resistor should be precise enough.

[问：]:在哪里下载本次在线座谈的各种播放资料？

[答：]:Please contact ChinaECnet.

[问：]:在使用AD524，发现增益会随输入电压的增大而减小，应怎样解决。

[答：]:Please to call to our Shenzhen office @(0755)378-1959. We need to dicuss with you about your circuits and PCB layout to address this issue. Thanks!

[问：]:在我所设计的ADuC812控制器的3个应用中，重新编程后常发生系统工作不正常的情况，常导致仿真开发系统不能进入？

[答：]:Did you provide a power up reset on the ADuC812? It needs to be provided a reset pulse to get this work correctly.

[问：]:在选择产品的基础上，请介绍那种噪声更小？

[答：]:Normally, the OP-Am's specifications I2n or V2n can provide this information to you. But you have to have a noise ideas your system need on mind first.