Search tips
Showing 41 results View by: Thread Post Sort by
    Answered

  • WEBENCH® Tools/OPA859: Why is the Gain Bandwidth required in the Filter Design Tool Always so high?

    Resolved
    Part Number: OPA859 Tool/software: WEBENCH® Design Tools I'm trying to design to a a bandpass filter with the filter design tool and I'm struggling to understand a few things from the design. The design parameteres required is a filter with a:…
    • Resolved
    • Answered

  • OPA859: Input common mode capacitance

    Resolved
    Part Number: OPA859 Hi, I am working on a differential probe with a the first opamp stages being OPA859's. The input common mode capacitance is said to be 0.62pF. I could not find any reference regarding any change of that capacitance based on biasing…
    • Resolved
    • Answered

  • TINA/Spice/OPA859: Weird behaviour of output during power down

    Resolved
    Part Number: OPA859 Other Parts Discussed in Thread: TINA-TI , Tool/software: TINA-TI or Spice Models Hi, I was trying to confirm the impedance of the OPA859 during a power down condition. It turns out that the "high impedance" stated in the datasheet…
    • Resolved

  • RE: OPA858: how to expand

    Hello Chi, Thank you for the additional information! With a high bandwidth requirement, the OPA858 can handle an input capacitance of around 4 to 5pF at 20kOhms. With the additional gain setting in the feedback, this value would decrease. I would recommend…

  • OPA858DSGEVM: OPA858DSGEVM || TIA Design for 500MHz input frequency

    TI Thinks Resolved
    Part Number: OPA858DSGEVM Other Parts Discussed in Thread: OPA858 , OPA859 Hi, In the layout of evaluation board of OPA858 and OPA859, what is controlled trace impedance and type of the main signal trace? Which of the following is it? 1)50ohms normal single…

  • OPA695: noise behavior of the device down to low offset freq?

    TI Thinks Resolved
    Part Number: OPA695 Other Parts Discussed in Thread: OPA859 , LMH6702 Hello, The OPA695 was used in a low phase noise amplifier configuration for a 10MHz / 100MHz system clock distribution circuit. Studying the datasheet, all noise sources (noise voltage…
    • Answered

  • RE: OPA858DSGEVM: OPA858DSGEVM || TIA Design for 500MHz input frequency

    Resolved
    Hello Shine, You may use a 500Ohm gain factor instead of the 1.5k. Using the TIA calculate above, the resulting Cf is at least 250f which will give you above 1GHz BW without accounting for additional parasitic on the board. Using Kai's simulations:…

  • RE: OPA858: Gain Switching for OPA858

    Hello Christian, That is a good debug method. The reason it could be stopping the hf ringing with the OPA859 is because like you said due to its lower bandwidth. The loop-gain crossover (AOL and noise gain intersection) occurs sooner (lower in frequency…

  • OPA857: low-noise alternative

    TI Thinks Resolved
    Part Number: OPA857 Other Parts Discussed in Thread: LMH32404 , LMH32401 , OPA818 , OPA859 Hello, team. Could you please suggest, do we have any updates of OPA857 device? Customer is wondering if we can propose any modern alternative with better noise specs…

  • RE: OPA855: How to design a TIA with OPA855?

    Hello, Thank you for the additional scope shots. That is a very small input capacitance, can you remove the feedback capacitor. The parasitic from the board should be enough in this case to stabilize the amplifier. For this type of application, I wouldn…

Didn't find what you are looking for? Post a new question.