Hi
I set up a Non-inverting amplifying circuit with OPA2187, the diagram showed as below picture.
when I add the voltage into the Non-invertering input pin, there are some problems with the output voltage. for example, when add 0.5V into pin 5, the voltage of pin 7 will be 1V. But sometimes, the output voltage will become 1.024V. see the below first picture. When I changed R5 from 10K to 5.1K, this situation happened more often. see the below second picture.
I don't know why the output voltage sometimes become more than twice the input voltage.
Looking forward to your reply.
thanks and best regards
Kim