1 to 10 ns pulse width. Rise/fall need to be good enough to get 1ns pulse with decent shape (this signal will be fed into a gan driver). For a 1-ns pulse width 1ns rise/fall time are clearly not enough. Also, si5351 has fixed duty cycle and is limited to 200MHz so can't use this directly to generate 1ns pulse width.
I'm wondering if there is a clever way to achieve what I need.
I could also use a AND gate with the clock signals from the si5351 shifted (starting from 180°) to achieve overlap.