I am just using a reference design of SMPS (from Microchip) to boost input voltage from 12V to 90V as the image below: It's working normally but the problem is the noise at the output of 90V. I measured the amplitude Vpeak-peak of noise around 150mV and the repetition frequency is 110kHz = switching frequency of HV9110 controller.
My question is how can I reduce this noise to 20mV because it will affect on my signal analysis.
Please help me and thanks in advance!!!