• Query on resistor value of LT5400


    According to the datasheet, the difference between LT5400-3 and LT5400-4 is only for the resistor value.

    What will be the biggest impact if I change to the part to LT5400-4 instead of LT5400-3? *in existing design was using LT5400-3.

    Also considering…

  • LT5400 Derating Curve


    My customers are considering using the LT 5400.

    Is there data on the Derating Curve( Ta ) of the LT 5400?

    Or is there a graph of Power Dissipation vs Thermal Resistance Curve?

    Best regards,


  • LT5400 - Matching Ratio Temperature Drift - stability, different parameters

    In our design we require the Temperature Coefficient of the Resistor's Matching Ratio will be max 0.2ppm/°C ( "0.2ppm/°C Matching Temperature Drift" as per datasheet). That is the most important parameter in the design.

    I can see…

  • Wide Bandwidth Discrete Programmable Gain Instrumentation Amplifier Design


    This KWIK (Know-how With Integrated Knowledge) Circuit FAQ is a step-by-step guide that goes through the key considerations when designing a wide bandwidth discrete programmable gain instrumentation amplifier (PGIA).

    The circuit highlighted in…

  • RE: Differential Amplifier with higher gain bandwidth??


    Lower gains can operate up to the MHz-range but unfortunately for G=1000, highest BW is up to 150kHz only.
    Another solution you can try is to use discrete circuits - differential amplifier + resistor network. 
    You can check LT5400-2, a quad matched resistor…

  • RE: LT6658 with voltage divider on output


    The resistors I have are .1% and 25ppm so I was hoping they would be good enough especially as you pointed out with the ratiometric measurement. The CN0545 is exactly what I am following but with the AD7124-8PMDZ board. This will be interfaced to…

  • RE: ADA4817 differential probe


    Yes it is quite hard to find a discrete diff amp with wideband as 200MHz.

    You can opt to use ADA4817 but I suggest, you have to use matched resistors network rather than discrete one.
    You can check LT5400 for quad matched resistor network.

    The LT5400…

  • RE: There is an error at the output due to the resistor matching. How can I minimize or eliminate this error?

    Fully differential and difference amplifiers usually have very high common-mode rejection (CMRR).  In practice, when resistors are configured around the amplifiers, the matching of those resistors can often dictate the overall CMRR.  What you have observed…

  • RE: Instrumentation Amplifier Gain resistor(s)


      You will find that the majority of error, especially over temperature, usually comes from the resistors.

    You can go to Digikey.com and buy 5%, 2%, 1%, 0.1% resistors, etc. with tempcos of 50 ppm, 25 ppm, etc.

    but the best thing is to use a monolithic…

  • RE: ADA4870构成电流源的过压保护问题


    1. 检测输出端过压,然后需要关闭的是电源而不是输出端,因为你是恒流源输出,相当于用一个高阻堵住了电流,但是这样你的恒流源电路会失效,可能会导致运放饱和。所以我觉得关闭电源也许会更好;

    2. 这个电流源的拓扑的输出阻抗会受到两个5k和1k的电阻对的匹配度的限制,所以更好的选择如下:

    记住差动放大器的比例电阻一定选择0.1% 以上精度,最好可以选择LT5400-3,以实现86dB的CMRR。