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TLV2404: TLV2404ID -Transimpedance Amplifier Operation

Part Number: TLV2404
Other Parts Discussed in Thread: TLV9104, , TLC2274, OPA1671, OPA170

Hello TI- Team 

We are using this Opamp as a 4 Channel TIA- Where we find there is no linear response and each channel has been tested individually.

Please let us know how do we resolve this Problem??.TIA Report 30-05-2023.pdf

Attached is the details of the test done.

Thanks

Krishna.P.N.

  • Hey Krishna, 

    Thanks for attaching the report, it provides a lot of details. However, could you please share the input (SMU) frequency? 
    Looking at the test results, since some of the outputs are close to the rail (±5V), the op amp is entering into a non-linear state due to either: 

    • I/O limitations
    • Bandwidth limitation 

    Additionally, could you please share why you have chosen to use the TLV2404 instead of the new alternative TLV9104? Is there a parameter of interest? 

    I plan to use the following circuit design to facilitate the rest of the support, please feel free to reference it yourself if that is faster: Transimpedance amplifier circuit 

    All the best,
    Carolina

  • Hello Carolina

    1)We had originally Chosen TLC2274 as we needed Dual Supply (+/-5V)& Input range of Current is +/-10nA to+/-1ma with 4 channels. 

    1a)We tested TLC2274 & Found with 1K Feedback resistor all 4 channels saturate even with +/-0.1mA input Current

    2)Since TLC2274 -SOIC package also did not have linearity and facing similar Saturation, one Equivalent was TLV2404

    3)I am not convinced on ur answer of IO & BW Limitations as we are giving DC current and even with 1 Mega ohm feedback Resistor we are not getting proper linearity.

    4)The Current input is only +/-0.3mA to +/-0.4mA for 1K Feedback Resistor, it Saturates at less than 1/10th of Max Input Current

    5)How do you think with above requirement your Suggested Parts OPA170/OPA1671 will resolve the issue??- Please clarify

    Thanks 

    Krishna.P.N.

  • Hey Krishna, 

    Understood on the DC test, no expected frequency.

    TLV2404 is not an equivalent part to the TLC2274, it's about a tenth of the short circuit current. 
    In the test report attached, the input current of ±400uA, this is outside of the spec of the device: 

    Which explains why the test report shows non-linearity at the extremes: 

    Instead I recommend testing with OPA4991IDR. Here is a test sim: TIA_2991.TSC

    All the best,
    Carolina 

  • Carolina

    TLV2404 output Current is very low but TLC2274 Output Current is +/-50ma

    Can we get OPA4991IDR-SOIC Package 1-2 Samples from TI for Testing and then we will order once protos are working fully

    Thanks n regards

    Krishna.P.N.

  • Hey Krishna, 

    Yes this can be done through your local TI sales representative. 
    I will message you with their details. 

    All the best,
    Carolina 

  • Carolina

    I have not heard from TI-Local Sales rep so far and i have sent 3 emails so far!!

    Can u please check and let me know

    Thanks

    Krishna.P.N.

  • Hey Krishna,

    Were you unable to sample from the web directly?

    On the product page https://www.ti.com/product/OPA4991, in the ordering and quality section, you can click request sample and receive a small number of samples online.

    If this does not work, we can reach out internally to the local sales representative.

    Best,
    Jerry