Hi expert,
I configured OPA365 as -1V/V gain converter as below circuits shows, powered by a -3.3V single supply. I measured the -3.3V supply power up quickly from 0V to -3.3V within 100us. I found the output of OPA365 also has a 100us and -3.3V spike(shown as below screenshot), then ramp down to the wanted -600mV when input is 600mV. The -3.3V spike still happens even if I keep the input short to GND/0V as below circuit shows. In this test, I disconnected the load from OPA365 to make it isolated. At present, I have to add a RC filter (1kohm, 1uF) at output to cancel the spike for protecting the load.
I would like to know what makes the spike. Thanks.
