Measuring the Slew Rate - test setup

[bababui]

Slew Rate

Hello,
I am trying to check the slew rate of my two stage differential input and single output amplifier. And I just want to make sure I'm seting up the test correctly.
I connected the opamp in unity gain configuration ( shorted negative input to output), and connected V common mode to the positive terminal. Now, do I just apply a square wave to the negative input? I'm a bit confused about that because it's also shorted to the output.

 

[LvW]

Re: Slew Rate

Hello,
...............
Now, do I just apply a square wave to the negative input? I'm a bit confused about that because it's also shorted to the output.

And exactly that´s the reason to feed the step into the positive input.

 

[bababui]

Re: Slew Rate

yes, I'm embarrassed, thank you. I'll think before I ask next time.

 

[karesz]

Slew Rate

Hi babaui,
If you desire to measure it more exactly; you can find such good circuits by Linear Technology & National Semi - Applications Books...
K.