OPA541 as voltage follower (Buffer)

I want to use OPA541 as a buffer simply to provide more current on the output. On simulation level everything works fine, any way the circuit is simple enough. Recently I bought an OPA541 and try to build everything but the circuit simply doesn't work as expected. Attached you can find the circuit topology. As input I used a square wave at 1kHz with vpp 4 V (0-4V) and connect the output directly to the osci. My output is a distorted signal which seems to oscillate up to V+ but it doesn't follow the input. I should say that no decoupling or other type of capacitor was used in this phase. Does anybody have an idea what is wrong?

Hi,

I should say that no decoupling or other type of capacitor was used in this phase.

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--> Read section 9 and section 10 of the datasheet. It is very clear in this.

As input I used a square wave at 1kHz with vpp 4 V (0-4V)

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With high dV/dt you may overdrive the input stage of this relatively slow OPAMP causing instabilities.
The OPAMP´s output is limited to about 6V/us slew rate...
--> I recommend to limit the input slew rate to an appropriate value.

and connect the output directly to the osci.

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Often this is no good idea, because a scope cable my be highly capacitive. And capacitive loads are difficult to drive ... causing ringing or oscillations.
--> a small series resistor should prevent from oscillations.

My output is a distorted signal which seems to oscillate up to V+ but it doesn't follow the input.

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--> A scope picture with input and output signals could give additional information.

Added:
Also check "Input common mode voltage range" and "Output voltage swing".
--> I recommend to use higher supply voltage.

Klaus

Problem solved. probably wrong or bad connection. The opamp can pass sine wave with up to 400khz without any distortion or amplitude mismatch. Thanks anyway for your feedback