OPA858-Q1: How is common-mode input capacitance measured?

Lauren Mayfield

Expert 7985 points

Part Number: OPA858-Q1

Tool/software:

For this part? What is the process? Do we measure from input pin to negative supply voltage?

11 months ago

0 Alec Saebeler 11 months ago

TI__Mastermind 23619 points

Hello Lauren,

We have some prior threads with good content here:

https://e2e.ti.com/support/amplifiers-group/amplifiers/f/amplifiers-forum/900884/opa858-input-capacitance-calculation

https://e2e.ti.com/support/amplifiers-group/amplifiers/f/amplifiers-forum/737482/how-to-measure-actual-input-common-mode-and-differential-capacitance

https://e2e.ti.com/blogs_/archives/b/thesignal/posts/input-capacitance-common-mode-differential-huh

https://www.planetanalog.com/input-impedance-extraction-and-application-for-high-speed-amplifiers-insight-9/

https://e2e.ti.com/support/amplifiers-group/amplifiers/f/amplifiers-forum/1015602/opa859-q1-what-are-common-mode-input-capacitance-and-differential-input-capacitance

https://e2e.ti.com/support/amplifiers-group/amplifiers/f/amplifiers-forum/809265/opa859-input-common-mode-capacitance

I do apologize for the barrage of links, but these are all helpful and will give you a starting point for understanding the specification, measurement, and context.

Best,

Alec

Amplifiers

Amplifiers forum

OPA858-Q1: How is common-mode input capacitance measured?