OPA858: input capacitance in the Spice model

Pavel Margulis

Prodigy 70 points

Part Number: OPA858

Hi,

The OPA858 Spice model states that both a common mode and a differential input capacitances are 0.05 pF.

Its data sheet shows 0.62pF and 0.2 pF, correspondently.

Why is such a difference? Is this from the package?

Thank you

over 2 years ago

0 Michael Steffes over 2 years ago

Guru 47515 points

I had done some model testing a while back, the input C's look good in simulation - recall internal to model there may be more than just a simple C hanging on the nodes.

4527.OPA858 model testing.docx

0 Pavel Margulis over 2 years ago in reply to Michael Steffes

Prodigy 70 points

I found it deep deep into the model's text. It is very complicated to read it out.

Thank you Michael.

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OPA858: input capacitance in the Spice model