I would like simulate a new buck converter design with the LT8608 including the external sync option in the MSOP package. I choose a higher resistor Rt to decrease the switching frequency, but it seems to me that the spice model of the LT8608 ignores the external clock on the sync pin with a higher switching frequency. I also performed a library update in LTSpice (Sync Release). In another test I replaced the LT8608 with the newer IC LT8608S and now the synchronization works fine. In my opinion the synchronization functionality in the LT8608 is not implemented as mentioned in the answer from "hyao" for the same question from the user "eglid" last year.