I am using systick interrupt to adjust timing to drive 5 digit 7 segment and it works fine. But when I implement capsense, touch buttons works fine but displays don't blink as before. A problem occurs about display timing. What is the relation between capsense and systick interrupt?
Probably your systick handler gets interrupted by the interrupts Capsense uses. I would try to play around with the interrupt priorities. Flickering of the display occurs with only a slight bit of distortion.