OPA838: OPA838 to replace AD8051

The differential input voltage must not exceed 1 V.

Are you using this device as a comparator?

Hi Gary,

Can you please share the schematic of your test circuit so that it's easy to understand and root cause any issue. Also can you explain in some more detail what crosstalk are you seeing at the input side?

Regards

Anat

Hi Clemens,

 It looks that a comparator application but I'm not sure their spec. about thir differential input voltage.

The AD8051 would allow up to 2.5 V.

Please show the schematic; otherwise, it is not possible to determine what characteristics are needed.

Hi Anant,

 There's a blurry pic FYI. They find interaction between the two input when they use OPA838, so they float Vin- to test as the first fig. and see a similar waveform on it. What else do you need to know about the application? I can check it whth my customer.

 Or, any other op might have similar spec. as AD8051? I see LMH6642 at cross reference result to replace AD8051?

Thanks and regards,

Gary

The voltage of a floating line cannot be measured.

The schematic does not show what is actually connected to the inputs, or if there is any negative feedback.

Gary,

The input pin of an opamp should not be left floating, it will not work if done so.

So please can you ask your customer to share the schematic with actual connection and test condition in order for us to suggest any solution to their problem.

Regards

Anant