Hi Shyam,
I checked your input signal and found out that you are giving a step rise and fall time of 1ns in the current wave form. For such low rise and fall time you need the TIA bandwidth of over 350Mhz. But there OPA857 in low gain mode has bandwidth…
Part Number: OPA857 Other Parts Discussed in Thread: OPA855 , OPA856 Tool/software: Hi Experts, I'd like to know what would happen if the OPA857 is connected to a balanced photodiode configuration. This means that the OPA857 will have sink and source current…
Forgot to mention this:
The supply voltage on the board is +/-5V. One of the cross reference searches on the TI website showed the OPA856. The pkg is wrong but the supply voltage is rated to 5.5V max so two strikes.
For the higher frequency noise, i directly measure the node without wires, then oscillation can be removed
LMH34400 TIA with TLV3601 comparator.pptx
However, for the very large input current at the TIA circuit, there are relatively low frequency fluctuation…
Hi Adrien,
Looking closer, you are correct that you will face some oscillation issues because the feedback capacitance would have to be large in order to achieve stability. Because of this, a unity gain stable op amp like the OPA856 will suit you better…
Hi Benham,
The OPA837 is the best match for your system requirements as many of our transimpedance amplifiers have much higher power consumption than the OPA837/OPA838. The OPA837 is also unity gain stable. The OPA837 however, does have a larger voltage…
Hello Nick, Thank you for your reply. The minimum gain of the OPA855 is 7V/V. Since the input of the TIA is current and the output is voltage how to calculate the gain of the TIA? Also, the simulation of the circuit OPA856 works well for our application. …
Hi Antonio,
Here is a possible circuit configuration with the OPA855 as your TIA stage and the OPA856 as an integrator stage. The integrator stage also inverts the output of the TIA stage. You can use the integrator circuit design notes ( found here )…
Hi Harshini,
I apologize for the late reply. I was working on your circuit but was running into issues with signals 1MHz and above and stability when using faster parts. It appears that you have fixed the configuration to meet the speeds of your signal…
