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…
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…
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:…
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…
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…
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…
Part Number: OPA855-Q1 Other Parts Discussed in Thread: OPA858-Q1 , OPA859-Q1 , Hi team,
Is it high impedance output in the case "power down connection" is on low logic?
How does "power off mode" makes OPA855-Q1, OPA858-Q1, and OPA859…
Part Number: OPA856 Other Parts Discussed in Thread: OPA859 , OPA857 , OPA855 , OPA2837 , OPA837 , TMUX1109 For test and measurement purposes, a design with switchable gain (x1, x10 and x100) and switchable filter (100 kHz, 1 MHz, 10 MHz, full [>100 MHz]) …
Hi Jimmy,
We don't currently have a specific reference design for differential probes, however I can suggest some parts that may work.
The biggest challenge with the specs you listed is finding a part with the needed common mode range that also has…
Thank you Sima for suggesting the OPA859. I looked at this part as well as the OPA858 however I was concerned that they were really meant as trans impedance amplifiers. Is this part reasonable to use with a voltage pulse source as we have here?