• 将AD768电流放大后的电压输出无变化

    我按照数据手册中的下图连接方式将AD768的输出电流转换成电压值。

    放大器用的是AD811,Rfb用的是120R。时钟信号的输入是晶振产生的27M的正弦波。

    其他的连接全部是按数据手册中来的。参考电压用的是内部2.5V参考电压,参考电压的输出是正确的。

    16个数据位的输入无论是固定在0还是65535,还是别的其他值,放大器的输出都是-2.4V左右,不会有改变。

    问:可能是哪些原因造成的这种错误呢?是晶振?还是对AD768的操作有错误?

    请帮忙解答一下,谢谢

  • RE: Need a High Speed OpAmp ?

    Hi YSVenu,

    The AD811 has a dual counterpart, the AD812. I think this would be a good fit for your application.

    I hope this helps.

    Thanks!

    Kris

  • RE: I-V converter for PMT

    Hi all,

    After all, thanks a lot for your answers. To tell you the truth, It is too difficult to explain my problems.

    So, I'd like to show some images from my system. I totally agree with OliverSedlacek's opinions, and I changed the feedback resistor…

  • RE: AD8099 oscillation

    FormerMember
    FormerMember

    dillian,

      You are using an op amp that is three times higher gbw than the AD811 on the eval board.

    Faster is not always better.  I would use ADA4895-1, ADA4897-1, ADA4891-1 instead of

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      With any high speed op amp, you need two bypass caps…

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    Hi Tomas,

    Thank you for considering ADI products for your applications. Based on your requirements, the most suitable current feedback amplifier that I can recommend is the AD811. It can be powered up to 36V. It has a typical slew rate of 2500 V/us and…

  • RE: AD811AR: Suggestion for good power dissipation layout

    FormerMember
    FormerMember

    larsen,

      Note that AD811AR is a leaded part, the AD811ARZ would be the RoHS part.

    The AD811 came out in 1991, so another way of reducing power dissipation is to use a newer part, built

    on a more effecient process.

    If you are driving video in coax…

  • RE: Power Amplifier for acoustic transducer

    Hi Asaf,

    Unfortunately we currently don't have devices that can support your requirements for your application. However, I can give you some design guide that might help you to achieved your applications requirements. You can start by bootstrapping your…

  • RE: 30MHz triangle wave amplifier question

    As I understand it you need an amplifier with a gain of 30 (15V out, 0.5V in) and 10 MHz bandwidth. This means you also need a slew of at least 1000 V/usec. The AD811 is suitable.

  • 回首2017,展望2018

         2017那些与ADI一起“芯动”时刻: 从2016年加入ADI中文技术论坛以来,2017年是我与ADI接触最多的一年了!

         通过在论坛里尽自己所能回答问题,不仅仅是帮助别人,更是自己学习的过程。最重要的是,论坛中的相关的设计资源丰富,作为一名电子工程系的学生,这些跟工程设计紧密相连的资料比起课本知识,收益更大!

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    Hi Tim,

    For the LT1006, I think the ADA4638-1 is an excellent part as replacement. ADA4638-1 is a high voltage, high precision, and zero-drift amplifier with rail-to-rail output. It has lower input offset voltage and drift, lower offset current, and…